FINAL REPORT ON ASSESSMENT OF THE QUALITY STATUS OF THE TRANSBOUNDARY WATER BODIES (COASTAL, LAKES, RIVERS) IN GAUJA/KOIVA RIVER BASIN DISTRICT Riga, 2013 Editors: Ilze Kalvane and Kristina Veidemane Authors: Ingmar Ott, Peeter Pall, Karin Pachel, Rita Poikane, Juris Aigars, Gunta Spriņģe, Agnija Skuja, Laura Grīnberga, Jānis Birzaks, Ivars Druvietis, Inga Konošonoka, Madara Alberte, Atis Labucis, Henn Timm, Sirje Vilbaste, Kairi Maileht, Katrin Saar, Teet Krause, Anu Palm, Aive Kõrs, Katrit Karus, Tõnu Feldmann, Rein Järvekülg. Contributions: Ilva Cimdiņa, Laura Bramane, Diāna Stendzeniece This report shall be cited: Kalvane I. and Veidemane K. (eds.). 2013. Final report on assessment of the quality status of the transboundary water bodies (coastal, lakes, rivers) in Gauja/Koiva river basin district. Maps: Sandra Sprukta (LHEI) 2 Contents Introduction ................................................................................................................................................... 5 A. Background ............................................................................................................................................... 6 A. 1. The key aspects in river basin management plan development ....................................................... 6 A.1.1. River basin management plans of Gauja and Koiva .................................................................... 6 A.1.2. Designation of the water bodies in Gauja and Koiva RBD .......................................................... 7 A.1.3. Ecological quality status of surface water bodies in Gauja/Koiva RBD ....................................... 9 A.1.4. Description of surface water bodies investigated within the Gauja/Koiva project .................. 10 A. 2. WFD requirements on typology of surface water bodies ............................................................... 11 A.2.1. Comparison of the existing typology of river water bodies ...................................................... 11 A.2.2. Comparison of the existing typology of lake water bodies ....................................................... 14 A.2.3. Comparison of the existing typology of transitional and coastal waters ................................. 15 A.3. WFD requirements and classification of water bodies .................................................................... 17 A.3.1. Comparison of the existing classification of river water bodies ............................................... 17 A.3.2. Comparison of the existing classification of lake water bodies ................................................ 19 A.3.3. Comparison of the existing classification of coastal waters ..................................................... 21 B. Methodology overview ........................................................................................................................... 23 B.1. Sampling, treatment and class boundaries for ecological status assessment in rivers ................... 23 B.1.1. Benthic diatoms (phytobenthos) .............................................................................................. 23 B.1.2. Benthic macroinvertebrates ..................................................................................................... 25 B.1.3. Macrophytes ............................................................................................................................. 28 B.1.4. Fish ............................................................................................................................................ 30 B.1.5. Physico‐chemical quality elements ........................................................................................... 32 B.2. Sampling, treatment and class boundaries for ecological status assessment in lakes .................... 33 B.2.1. Phytoplankton ........................................................................................................................... 33 B.2.2. Benthic macroinvertebrates ..................................................................................................... 34 B.2.3. Macrophytes ............................................................................................................................. 36 B.2.4. Fish ............................................................................................................................................ 39 B.3. Sampling, treatment and class boundaries for ecological status assessment in the coastal waters
................................................................................................................................................................. 41 B.3.1. Sampling and treatment for ecological status assessment in the coastal waters .................... 41 B.3.2. Class boundaries for assessment of ecological status .............................................................. 43 B.4. Sampling and treatment methods for assessment of hazardous substances in transboundary waters ...................................................................................................................................................... 45 B.4. Sampling and treatment methods for assessment of hazardous substances in transboundary waters ...................................................................................................................................................... 45 B.4.1. Selection of matrixes, hazardous substances and sampling sites ........................................... 45 B.4.2.Sampling and handling ............................................................................................................... 46 B.4.3. Analysis of the samples ............................................................................................................. 47 C. Results of the investigations in transboundary waters of the Gauja/Koiva river basin district .............. 48 C.1. Locations for joint ecological status investigations of transboundary waters ................................. 48 C.2. Ecological status in the transboundary river water bodies .............................................................. 49 C.2.1. Ecological status according to biological quality elements ....................................................... 49 3 C.2.2. Physico‐chemical water quality in transboundary rivers .......................................................... 52 C.3. Ecological status in transboundary lakes ......................................................................................... 54 C.3.1. Water quality according to biological quality elements ........................................................... 54 C.3.2. Physico‐chemical water quality in transboundary lakes ........................................................... 56 C.4. Water quality in coastal waters ....................................................................................................... 57 C.5. Assessment of Hazardous substances in transboundary water bodies ........................................... 58 C.5.1. Water ......................................................................................................................................... 58 C.5.2.Sediments ................................................................................................................................... 58 C.5.3. Biota .......................................................................................................................................... 59 D. Assessment results of ecological status in transboundary water bodies ............................................... 61 D.1. Results of assessment of ecological status in transboundary water bodies ................................... 61 D.1.1. Ecological status assessment in rivers ...................................................................................... 61 D.1.2. Ecological status assessment in lakes ....................................................................................... 62 D.1.3. Ecological status assessment in coastal waters ........................................................................ 64 E. Conclusions and Proposals ...................................................................................................................... 65 E.1. Alignment of the typology of the transboundary surface water bodies in the Gauja/Koiva river basin district ............................................................................................................................................ 65 E.1.1. Typology of rivers ...................................................................................................................... 65 E.1.2. Typology of lakes ....................................................................................................................... 65 E.1.3. Typology of coastal waters ........................................................................................................ 66 E.2. Harmonisation of water quality classification system for transboundary water bodies in the Gauja/Koiva river basin district ............................................................................................................... 66 E.2.1. River water quality classification system .................................................................................. 66 E.2.2. Lake water quality classification system ................................................................................... 67 E.2.3. Coastal water quality classification system ............................................................................... 68 E.3. Water quality assessment schemes for the transboundary water bodies in the Gauja/Koiva river basin district ............................................................................................................................................ 68 E.3.1. River water quality assessment scheme ................................................................................... 68 E.3.2. Lake water quality assessment scheme .................................................................................... 69 E.3.3. Coastal water quality assessment scheme ................................................................................ 70 E.4. Recommendations for further investigations on water quality ....................................................... 70 E.5. Proposals for the 2nd Gauja/Koiva RBMP to be produced by 2015 .................................................. 71 4 Introduction Typology and ecological status are among the important prerequisites forming a basis for assessing the water quality and defining environmental objectives during the development of a river basin management plan (further – RBMP). These two systems are elaborated based on knowledge about natural conditions of water bodies and the impacts of human activities on them. For setting up typology and water quality classification systems which would be comparable in EU the key steps are laid down in the Water Framework Directive (further ‐ WFD). However, each Member State has a kind of flexibility in adjusting these systems by the use of descriptors and parameters. Consequently, it has lead to different approaches in developing national classification systems thus constraining comparisons in straight forward way between the countries sharing a river water body. The project “Towards joint management of the transboundary Gauja/Koiva river basin district” (further ‐ Gauja/Koiva project) amongst others aims at clarifying and setting common water quality objectives for the shared Estonian‐Latvian river basin district. As defined by the WFD the overall water quality objective is to achieve good ecological status in all surface water bodies in the river basin district. With regard to the transboundary water management, one of the key challenges is the definition of the common environmental objectives (or what is understood by “good”) according to the exact different biological and chemical quality elements. To attain the common definition the both countries shall coordinate their typology and water quality classification systems at least to ensure comparability in assessment of transboundary water bodies. The tasks of this Report are to present the results of the Gauja/Koiva project with regard to:  alignment of the typology of the transboundary surface water bodies in the Gauja/Koiva river basin district;  harmonisation of water quality classification system for transboundary water bodies in the Gauja/Koiva river basin district;  water quality assessment schemes for the transboundary water bodies in the Gauja/Koiva river basin district;  recommendations for further investigations on water quality;  proposals for the 2nd Gauja/Koiva RBMP to be produced by 2015. The Report is based on the results of the joint investigations carried out at the transboundary surface water bodies of the Gauja/Koiva river basin district in 2011‐2013 as well as accompanying Estonian and Latvian expert discussions in cross‐border workshops on the water quality classification and assessment. This Report shows the key outputs relevant to establishing a common approach to typology, water quality classification, water quality assessment as well as setting up water quality objectives for transboundary water bodies in Gauja/Koiva river basin district. Additionally, we encourage you to get acquainted with all investigatory work performed in the frame of the project. The relevant reports are referenced in the Report and are available from the project web‐site: http://gauja.balticrivers.eu. 5 A. Background A. 1. The key aspects in river basin management plan development A.1.1. River basin management plans of Gauja and Koiva
The first river basin management plans (RBMP) are valid for the period of 2010‐2015. According to the WFD the RBMP are produced for each river basin district (further – RBD) which are defined as the area of land and sea, made up of one or more neighbouring river basins together with their associated groundwater and coastal waters. In the case of an international river basin district falling entirely within the Community, the Member States shall ensure coordination with the aim of producing a single international river basin management plan. Where such an international river basin management plan is not produced, the Member States shall produce river basin management plans covering at least those parts of the international river basin district falling within their territory to achieve the objectives of WFD. Due to restricted timing and resources, Estonia and Latvia developed individual RBMPs – one for Koiva1 and one for Gauja2 basin RBD. Although the exchange of information about the progress in preparation of the RBMP was organised in the frame of the implementation of the bi‐lateral agreement on cooperation in protection and sustainable use of transboundary water courses (signed in Palanga, in 2003), no efforts were taken to harmonise methodologies related to elaboration of the key elements of the RBMP (Fig. A.1.1.). Therefore, the differences between the 1st Gauja and Koiva RBMPs exist. Figure A.1.1. Development of Gauja/Koiva river basin management plan 1
http://www.envir.ee/1152634 http://www.varam.gov.lv/lat/darbibas_veidi/udens_aizsardziba_/upju_baseini/ 6 2
The WFD defines the content which should be covered by the RBMP. The key elements are as follows: 1. A description of the river basin district, including maps (outcome of Art. 5) 2. A summary of the main significant pressures and environmental impacts of human activities (outcome of Art. 5) 3. A summary of the economic analysis of water use (outcome of Art. 5) 4. A map of specially protected areas (e.g. drinking, natural habitats) (outcome of Art. 6) 5. A map of monitoring networks, and results of the monitoring (outcome of Art. 8) 6. A list of environmental objectives or targets (outcome of Art. 4) 7. A summary of the programme of measures to maintain or improve water status (outcome of Art. 11) 8. A summary of public information and consultation measures and their influence (outcome of Art. 14) 9. A list of competent authorities and contacts. A.1.2. Designation of the water bodies in Gauja and Koiva RBD
River basin district (further – RBD) are made up of one or more neighbouring river basins. Although the WFD endorses setting up the water management according to natural boundaries of river basins, actual designation of the RBD (the main river management unit) might bring incoherent result if one looks in the transboundary context or beyond the national borders. This is also a case with setting boundaries of the RBDs between Latvia and Estonia where the present alignment of management units are incompatible with the hydro‐geographical conditions (Fig. A.1.2.). Reasons for inconsistency in identification of separate water bodies as well as assignment to RBD ‐ are twofold: difference in typology (mainly the size of catchment area) and the practicality in administration of management measures. Figure A.1.2. Gauja/Koiva river basin district in Estonia and Latvia. During 2003‐2004, Estonia and Latvia designated Gauja and Koiva RBD as a transboundary one between both countries. In general, Gauja RBD consists of the Gauja river basin, the Salaca river basin, the basin of small rivers of the Gulf of Riga and the basin of small rivers between Gauja and Salaca. Smaller bordering river basins, geographically belonging to the Võrstjärve Lake basin, has been designated to the Salaca river basin. Koiva RBD consists of the Koiva river basin and the Pededzi river basin. The latter actually belongs to the Daugava river basin. The overview on river basins and their assignments see in Table A.1.1 and Figure A.1.3. 7 Table A.1.1. Identified transboundary river basins and their designation to individual river basin districts in Estonia and Latvia River basin Assignment to the River basin district Estonia Latvia Gauja/Koiva Salaca/Salatse Koiva West‐Estonia (Pärnu river sub‐basin)
Gauja
Gauja
Rūja/Ruhja * West‐Estonia (Pärnu river sub‐basin) Gauja (Salaca sub‐basin) Ramata/Ramata * Pužupe***/Puzupe* Omuļupe**/ Õhne* West‐Estonia (Pärnu river sub‐basin)
West‐Estonia (Pärnu river sub‐basin)
East‐Estonia, Võrstjärve lake basin
Gauja (Salaca sub‐basin) Gauja (Salaca sub‐basin) Gauja (Salaca sub‐basin) Pedele**/Pedeli* East‐Estonia, Võrstjärve lake basin Gauja (Salaca sub‐basin) Pededze/ Pedetsi Koiva Daugava 2
* As the size of the water bodies in Estonia is smaller than 10km and the river basins are not considered to be at a risk not to achieve the good water status, then the countries have agreed that these rivers in Estonian part will be a part of the East‐Estonia river basin district. ** Omuļupe and Pedele are not identified as a separate water bodies in Latvia, but they are designated as a part of the Seda water body (G316), which is a part of the Salaca river basin. *** Pužupe is not identified as a separate water body but forms a part of the Salaca 2 water body (G301). Figure A.1.3. Transboundary river water bodies between Estonia and Latvia Regarding lakes, 8 lake water bodies have been identified in total in the Koiva basin, but just 1 (Murati lake) is the transboundary lake water body. The lake Murati is also designated as the lake water body in Gauja RBD. Another nationally designated border lake water body in Gauja RBD is the lake Sokas (E229) providing the source for Reiju/Reiu river. There are several smaller lakes shared by Estonia and Latvia, however, due to size they are not identified as separate water bodies for which the minimum size is 0.5 km2 or 50 ha. 8 Table A.1.2. Transboundary lakes in Gauja/Koiva RBD Lake area in Latvia (ha) area in Estonia (ha) Murati järv (Muratu ezers) 11.19 55.45 Kikkajärv (Ilgājs) 8.42 11.88 Pupsi järv (Pukšezers) 6.07 2.02 Pīrī (Glēzeris) 1.45 0.14 Mudajärv (Peļļu ezers) 0.49 0.05 Liivajärv (Smilšājs) 1.60 2.89 Väike‐Palkna järv (Mazais Baltiņš) 1.13 2.82 Sarapuujärv (Sūneklis) 0.27 2.04 A.1.3. Ecological quality status of surface water bodies in Gauja/Koiva RBD
One of the tasks in development of the RBMP is a review of the impact of human activity on the status of surface waters and on groundwater. Initially this task had to be performed by the end of 2004. When producing the draft RBMPs, the countries included actual information on the status of water bodies, respectively 2007/8 data were used for the Gauja basin, 2009 for the Koiva part (Table A.1.3.). In order to assess water status the WFD requires that the Member States establish the monitoring programme. According to the information reported to the EC, Estonia has established 17 monitoring sites (10 on rivers and 7 on lake) for Koiva RBD, while Latvia 45 on rivers and 35 on lakes in the Gauja RBD. When monitoring data were absent the assessment of status of the water body was based on pressure factors and, if possible, also expert assessments. In Latvia, the assessment of water quality was not carried out for all biological elements, but mainly for nutrients. Table A.1.3. Status of the monitored transboundary river water bodies as reported in Gauja/Koiva RBMP Water body in Estonia Quality class Water body in Latvia Quality class Koiva good G225 Gauja good G231 Gauja good Mustjõgi (5) good Ujuste good A part of G225 Gauja good A
Vaidava (until the impoundment PoorA G235 Vaidava good of Vastse‐Roosa), upstream A
Peetri (downstream Melnupe) high G233 Melnupe (downstreem) moderate A
G234 Melnupe (upstream) good Pärlijõgi (1) good G237 Mustigi (Pērļupīte) good Ramata* good G307 Ramata good Ruhja* good G312 Rūja moderate Puzupe good G 301 Salaca 2 moderate** Pedetsi (upstream) good D450 Pededze High * are part of the Pärnu sub‐basin. ** does not cover status of Puzupe river A
the status class was based on expert assessments; there were no data on individual quality indicators 9 A.1.4. Description of surface water bodies investigated within the Gauja/Koiva
project
During the Gauja/Koiva project, the main focus of the Estonian and Latvian experts was to harmonise ecological quality status assessment approaches and methods used in both countries independently so far. For that the joint and separate field investigations in the transboundary water bodies as well as in other smaller rivers and lakes located in this transboundary RBD were carried out. In total 72 river and 14 lake sampling sites were investigated for biological quality assessment (Fig. A.1.4.). Moreover, the river Abuls was investigated particularly to examine the significance of impacts from hydromorphological pressures. In the Koiva RBD, the selected 12 rivers/streams were also investigated for physico‐chemical quality assessment at monthly frequency for one year. A separate investigatory study dedicated to the presence and concentration levels of hazardous substances in biota and sediments took place in Gauja RBD in 2012. Additionally, Latvian experts surveyed quality of coastal waters at bordering area between Latvia and Estonia as well assessed impacts on coastal waters caused by input of the Salaca river basin. As the result of all investigations, the countries obtained new data from these additional monitoring activities so much needed for more comprehensive assessment of water quality status. You can find the detailed results presented in separate reports published on web‐
site: http://gauja.balticrivers.eu. In order to elaborate proposals to harmonise typology and quality classification, the joint sampling on transboundary rivers and lakes were performed in 2012 (see chapter C.1). Figure A.1.4. Distribution of sampling sites and polygon 10 A. 2. WFD requirements on typology of surface water bodies The WFD requires that the Member States identify surface water bodies within the RBD as falling within either one of the following surface water categories — rivers, lakes, transitional waters or coastal waters — or as artificial surface water bodies or heavily modified surface water bodies. For each surface water category, the relevant surface water bodies within the RBD shall be differentiated according to type. For artificial and heavily modified surface water bodies the differentiation shall be undertaken in accordance with the descriptors for whichever of the surface water categories most closely resembles the heavily modified or artificial water body concerned. These types are those defined based on abiotic descriptors using either ‘system A’ or ‘system B’ identified in the Annex II of the WFD. The main purpose of typology is to enable type specific reference conditions to be defined which in turn is used as the anchor of the ecological status classification system. The typology system in Estonia and Latvia has been adopted by legal acts:  Estonia: Regulation of the Minister of the Environment, 11/28/2010; https://www.riigiteataja.ee/akt/125112010015?leiaKehtiv  Latvia: Governmental Regulations No 858 „Regarding the Characterisation of the Types, Classification, Quality Criteria of Surface Water Bodies and the Procedures for Determination of Anthropogenic Loads”; http://likumi.lv/doc.php?id=95432 A.2.1. Comparison of the existing typology of river water bodies
Regarding typology of rivers, both Baltic countries have stated in their river basin management plans that the system B is introduced in the country. However, available information and characterisation about the descriptors practically used in defining types of the river water bodies in Estonia indicates that the system A has been implemented in Estonia up till now. As the result of chracterisation, 6 river types have been defined in Latvia and 7 river types in Estonia. The countries have generally used the “size of catchment” factor to identify the river water bodies as it is an obligatory factor of WFD. However the use of this factor differs between countries. According to the Latvian governmental regulations (Nr. 858) the river water bodies are defined larger than 100 km2. Smaller units are set only when it is necessary to achieve environmental objectives (e.g., due to nature protection needs). Estonia has used “geology” as second factor for differencing water bodies – which is also obligatory factor of WFD. Two categories are distinguished” low and high organic content. It has been stated that the “Geology” factor is not applied by Latvia as a majority of rivers are calcareous. Latvia also uses the soil descriptors for grouping of the rivers in types: i) sandy and stony sediments or (ii) sandy and silty sediments covered by organic debris. However, this has been declared as optional factor of WFD – “mean soil or substrate condition”. 11 Latvian legislation sets officially that “mean water slope” is additional factor for grouping rivers in types. According to the WFD this factor is treated as the optional one. As rivers are quite diverse in their flow, during the monitoring the experts take samples from most typical, characteristic stretch. The present knowledge about the Estonian rivers in Koiva basin has determined that “size of catchment” is the only relevant factor to differentiate river water bodies with regard to physico‐chemical character of rivers. The monitoring results indicate that the water physico‐chemical quality status is independent on the previously identified abiotic factor ‐ organic content. Therefore, typology according to humic content needs to be revised and harmonised to fit both physic‐chemistry and biology media. Biological quality elements ecological status classification is based on the same typology as physico‐chemical elements according to Regulation of the Minister of the Environment 3 4. Table A.2.1. Typology of river water bodies in the Gauja/Koiva river basin district (“‐“not applied; “X”‐ applied) Factors (WFD) Obligatory factors Size of catchment Geology Optional factors Mean water slope Descriptor (WFD) Estonia
Latvia
Remark Small 10 ‐ 100 km2 X
< 100 km2
This type is used very rarely in LV, while very common in EE. Medium 100 – 1000 km2
Large 1000 ‐ 10 000 km2
Very large > 10 000 km2
X
X
X
X
> 1000 km2
‐
calcareous ‐
siliceous ‐
Organic: light, low content x
(CODMn <25 mgO/l) Organic: dark, high content x
(CODMn >25 mgO/l) -
rhithral river: slope >1,0 ‐
m/km within 1 to 3 km river stretch, sand and stone potamal river: slope <1,0 m/km within 1 to 3 km river stretch, sand and sylt, organic debris X X 3
https://www.riigiteataja.ee/akt/125112010015?leiaKehtiv https://www.riigiteataja.ee/aktilisa/1251/1201/0015/KKM59_lisa4.pdf# 4
12 Large rivers are not differentiated by geology factor in EE. This factor is not applied by LV as the majority of rivers are calcareous. Estonia is considering not to use this factor for typology Table A.2.2. Characteristics of transboundary river water bodies according to the typology Water body in Type
Estonia Koiva Large, light (IIIB) Water body in Latvia
G225 Gauja Ujuste Small, dark (IA) Vaidava Medium, light (IIB) Peetri Medium, light (IIB) Pärlijõgi (1) Small, dark (IA) Ramata Heavily modified G307 Ramata
Ruhja Small, light (IB) G312 Rūja Puzupe Heavily modified Pužupe is not defined as separate water body in LV, but just a part of G301 ‐
Õhne Medium, light (IIB) Omuļupe, belongs to Seda WB (316), Salaca river basin A separate water Pedele belongs to body in East Estonia Seda WB (316), Salaca RBD, small, light IB river basin Small, dark (IA) (at D450 Pededze Kivioru) Medium, dark (IIA) (at Missoküla) ‐
Pedeli Pedetsi Remark Large, The river water body in both potamal (6) countries is defined as large Large, potamal (6) ‐
It is recommendable to designate Kaičupe as separate water body in LV – type 1, small, rhithral G231 Gauja Kaičupe (Ujuste) is not defined as separate water body in LV, but just a part of G225 G235 Vaidava Medium rhithral (3) G233 Melnupe (lower, Medium bordering with EE) potamal (4) G234 Melnupe Medium rhithral (3) G237 Mustigi Large (Pērļupīte) potamal (6) Medium rhithral (3) Medium rhithral (3) 13 Type
‐
Large, rhithral (5) The river water body in both countries is defined as medium The river water body in both countries is defined as medium Upper part of Melnupe The river catchment of Pērļupīte is smaller than 100km2, there it is proposed to change the type to 1st type, small rhithral. In Estonia the river stretch is draining ditch The Ruhja’s source is in EE, thus catchment is small, while the largest part of WB is LV and corresponds to the medium size. In Estonia the river stretch is draining ditch. It is recommendable to designate Pužupe as separate water body – type 2, small, potamal Omuļupe has not been investigated. It is recommendable to designate Pedele as separate water body in LV– type 4, medium, potamal According to the size of the catchment of the water body and EE upstream water body (<1000km2), D450 river water body would need to be classified as medium, type 3. A.2.2. Comparison of the existing typology of lake water bodies
Similarly to rivers, the lake water bodies are also differentiated according to the types. Accordingly, 10 lake types are defined in for lakes in Latvia and 8 lake types in Estonia. Regarding lakes, the WFD also has set mandatory and optional factors for development of typology. Although the WFD has set the “size of surface area” of lake as mandatory factor, this factor has been implemented partly in Estonia by distinguishing large lakes as separate large lake water bodies ‐ lake Võrtsjärv (type VI) and lake Peipsi (type VII). Latvia does not differentiate lakes according to the type as all lakes are smaller than 100km2. In Estonia, the lowest surface size boundary is not set. The need to include also lakes below 0.5 km2 is due to requirement to monitor the lakes with the importance for nature protection. “Depth” is another mandatory factor of WFD. All Estonian lakes have mean depth between <15m, while mean depth of Latvian lakes are between 2‐9 m, therefore the differentiation has been introduced. However, the experts of the both countries consider that having lake stratified or none stratified is more relevant factor then depth. “Geology” factor described by conductivity values is used by both countries. The threshold value for defining soft lake is the same in both countries. Both countries use optional factors to achieve larger degree of differentiation. The common factor is “organic matter”. Instead of the hydrological depth the Estonian system has introduced to use functional depths of lakes defined by two descriptors – stratified or non‐stratified lakes. Table A.2.3. Typology of lake water bodies in the Gauja/Koiva river basin district (“‐“not applied; “X”‐ applied) Factors (WFD) Descriptor (WFD) Obligatory factors Size of surface area 0.5 to 1 km2 1 to 10 km2 10 to 100 km2 > 100 km2 Depth < 3 m 3 to 15 m > 15 m Geology calcareous Estonia
Latvia
<10 km2
‐
There is only one water body between 10‐100 km2 and heavily modified. Therefore this class is excluded. 100 to 300 km2 (Võrtsjärv)
> 100 km2
In EE 0.5 is not the lowest boundary for size, for nature protection reasons, smaller lakes are also investigated and assessed; Lakes are not differentiated by size in Latvia as there is also no lake > 100km2 Depth is differentiated by Very shallow (< 2 Experts consider that stratification m) the depth factor needs Shallow (2 to 9 m) to be reviewed as the factor on stratification Deep (> 9 m)
could be more relevant Hard (alkalinity >240 HCO3 Hard: Conductivity mg/l, >400 µS/cm) >165 μS/cm Medium (alkalinity 80– 240 HCO3 mg/l, 165‐400 14 Remark Factors (WFD) Descriptor (WFD) Estonia
Latvia
Remark µS/cm)
siliceous organic Optimal factors Water temperature ‐ and O2 regime Polyhumic Organic matter (brown) Oligohumic (clear) Soft (alkalinity < 80 HCO3
mg/l, < 165 µS/cm): ‐ ‐ Soft: conductivity <165 μS/cm ‐
‐
Stratified/Unstratified
‐
absorbance factor at 400 nm >4 m‐1, colour Pt‐Co scale Yellow substances absorbance factor at 400 nm <4 m‐1, colour Pt‐Co scale Colour >80 Pt/Co The same thresholds scale are applied in both coutnries Colour <80 Pt/Co This factor could be considered also as scale geological feature – organic descriptor The lake Murati is only transboundary lake water body as its surface area is larger than 50ha (or 0.5km2). In the Koiva RBMP ‐ the lake Murati is defined as type III according to the Estonian system – stratified lake with medium hardness. During the project, experts have re‐defined it as II type – non‐stratified lake with medium hardness. According Gauja RBDP, the lake Murati is defined as VI type – shallow hard water polyhumic lake. During the project, Latvian experts have confirmed the definition of the lake Murati as VI type. Two other transboundary lakes ‐ Kikkajärv/Ilgājs and Väike Palkna/Mazais Baltiņš ‐ jointly investigated do not meet criteria of being separate lake water bodies in Latvia as their surface area is about 20.3 ha and 3.95 ha, respectively. As both lakes are designated as Natura 2000 sites the experts recommend them to be designated as separate individual water bodies and to define them as follows:  The lake Kikkajärv/Ilgājs corresponds to the type: Estonia: stratified lakes with medium water hardness (III type); Latvia: deep hard water oligohumic (clear) lake (9 type)  Väike Palkna/Mazais Baltiņš corresponds to the type: Estonia: light and soft water, stratification is not important for this lake type (V type) Latvia: deep soft water oligohumic lake (10 type). A.2.3. Comparison of the existing typology of transitional and coastal waters
The transitional and coastal waters attributed to Gauja/Koiva RBD have been designed only in Latvia. Nevertheless, the coastal waters of Latvia are related to coastal waters of West Estonia, therefore this chapter reviews the comparability of the coastal waters. The transitional waters have not been identified as surface water category in Estonia. The factors of system B is applied for defining types for coastal waters in both countries and the descriptors have been harmonised. In the result, 6 coastal types have been identified in Estonia and 4 coastal types in Latvia. The bordering coastal areas are Gulf of Riga (Type VI) from the Estonian side and Gulf of Riga stony coast (subtype F 15 Eastern coast of Gulf of Riga‐ stony coast). Although the values of some parameters matches, nevertheless the water bodies are different due to substratum, ice coverage and residence time. Table A.2.4. Typology of coastal waters (“‐“not applied/relevant; “x”applied) Factors (WFD) Descriptor (WFD) Estonia Latvia Remark Obligatory factors mean annual < 0,5 ‰: freshwater ‐ ‐ Due to specifics salinity 0,5 to < 5 ‰: oligohaline 0,5 to < 6 ‰: 0,5 to < 6 ‰: of the Baltic, only 2 types are oligohaline oligohaline defined. The 5 to < 18 ‰: mesohaline 6 < 18‐20 6 < 18‐20 thresholds also mesohaline mesohaline have been 18 to < 30 ‰: polyhaline ‐ ‐ agreed. 30 to < 40 ‰: euhaline ‐ ‐ mean depth shallow waters: < 30 m Shallow < 30 m < 30 m Latvian coastal waters are intermediate: (30 to 200 m) Deep > 30 m ‐ shallow. deep: > 200 m ‐ Optimal factors wave exposure Very sheltered x ‐ sheltered x ‐ moderately exposed x x exposed x x mixing seasonally mixed x ‐ characteristics partially stratified x ‐ permanently fully mixed x x residence time Short ( <7 Days) x x Long (weeks) x ‐ substratum sand‐gravel x x mud‐silt, sand‐gravel x ‐ mixed sediments x ‐ sand‐gravel, cobble‐hard rock x ‐ cobble ‐ x mud‐silt ‐
x
ice coverage <90 x x (days) 90‐150 x ‐ Table A.2.5. Typology of the bordering coastal waters between Estonia and Latvia related to Gauja/Koiva basin Ice Salinity Mean Wave Residence Type Mixing Substratum coverage (PSU) Depth (m) exposure time (days) Gulf of Riga (EE) (4‐6)‐
18* Gulf of Riga 0.5 < 6 stony coast (LV) <30 shallow sheltered <30 shallow moderatel permanently y exposed fully mixed seasonally days mixed <90 <7 short cobble <90 irregular * Salinity in Estonian waters is higher as the waters for the Gulf of Riga type are also deeper there than in Latvia. 16 A.3. WFD requirements and classification of water bodies The WFD has set an objective that surface waters must achieve good ecological and chemical status, to protect human health, water supply, natural ecosystems and biodiversity. The definition of ecological status looks at the abundance of aquatic flora and fauna, the availability of nutrients, and aspects like salinity, temperature and pollution by chemical pollutants. Morphological features, such as quantity, water flow, water depths and structures of the river beds, are also taken into account. The WFD classification scheme for surface water ecological status includes five categories: high, good, moderate, poor and bad. The ‘High status’ means no or very low human pressure. ‘Good status’ means a ‘slight’ deviation from the ‘High status’ condition, ‘moderate status’ means ‘moderate’ deviation, and so on. To define good chemical status, environmental quality standards have been established for 33 new and eight previously regulated chemical pollutants of high concern across the EU. The WFD has set the quality elements structuring the classification system. These elements shall be commonly used in EU. However, the particular values assigned to assess the status of water bodies are set individually by countries at first, and then intercalibrated within one eco‐region. The intercalibration shall ensure that water bodies of the same type are assessed in consistent way all over Europe. The initial step in building the quality classification system is defining type specific reference condition which is a kind of benchmark of defining high status of particular water body type. Surface water status Chemical status Ecological status  fish  macrophytes  macroinvertebrates  phytoplankton/ phytobenthos  hydromorphology of water body (flow regime, damming, etc.)  water physico‐chemical characteristics
(temperature, transparency, nutrients (N, P), etc.) Hazardous substances in:
 water  fish/molluscs  sediments Figure A.3.1. Water quality elements for classification of water status A.3.1. Comparison of the existing classification of river water bodies
As Latvia has defined 6 river types and Estonia has set 7 river types, the countries had to define reference condition or high ecological status for each these types. While reference conditions have been described, unfortunately, the Latvian classification system is not elaborated to cover all biological elements as requested by WFD. Therefore comparison of biological elements is not possible by assessment of fish fauna, macroinvertebrates, marophytes or phytobenthos (diatoms). The physico‐chemical quality elements are those ones which could be comparable between the countries. In Estonia values of physico‐chemical quality elements varies depending on geological 17 typology factor (organic content), while the catchment area for water types smaller than 1000 km2 is not considered as essential criteria to differentiate the physico‐chemical values. However, the total nitrogen and total phosphorous values are the same for all types with the catchment area <1000 km2. In Latvia, the values are different for each type. The importance of the difference in these value will be reviewed when results of the joint sampling are presented. Table A.3.1. Ecological classification of rivers based on key physico‐chemical quality indicators in Estonia5 Quality indicator Unit
High Good Moderate Biochemical oxygen demand (BOD5) Arithmetic mean
mg O2/l <2,2
2,2–3,5 >3,5– 5,0
Total nitrogen (Ntot) Arithmetic mean
mg N/l <1,5
1,5–3,0 >3,0– 6,0
Total phosporus (Ptot) Arithmetic mean
mg P/l <0,05
0,05–0,08 >0,08–0,1
Biochemical oxygen demand (BOD5) Arithmetic mean
mgO2/l <1,8
1,8–3,0 >3,0–4,0
Total nitrogen (Ntotal) Arithmetic mean
mgN/l <1,5
1,5–3,0 >3,0–6,0
Total phosporus (Ptotal) Arithmetic mean
mgP/l
<0,05
0,05–0,08 >0,08–0,1
Types I A, II A and III A (dark) Types I B, II B and III B (light) As the result of additional investigations in Koiva river basin, the Estonian experts have concluded that there is no need to differentiate the river quality classification system according to the physico‐chemical quality indicators. The stronger values for BOD5 which now is defined for the type B water bodies is also reasonable for type A water bodies. Table A.3.2. Ecological classification of rivers based on physico‐chemical quality key indicators in Latvia6 Quality indicator Unit
High Good Moderate Biochemical oxygen demand (BOD5) Arithmetic mean
mg O2/l
<2,0
2,0 – 2,5 2,5 – 3,0
Total nitrogen (Ntot) Arithmetic mean mg N/l 3 type: < 1,8
1,8 ‐ 2,3 2,3 – 2,8
5 type: < 1,8
1,8 ‐ 2,8 2,8 ‐ 3,8
Total phosporus (Ptot) Arithmetic mean mg P/l Biochemical oxygen demand (BOD5) Arithmetic mean
mg O2/l
Total nitrogen (Ntot) Arithmetic mean mg N/l Total phosporus (Ptot) Arithmetic mean
mg P/l Types 3; 5 (rhithrial) 3 type: <0,05
0,05 – 0,075 0,075 – 0,100
5 type: <0,04
0,04 – 0,065 0,065 – 0,090
Types 4,6 (potamal) <2,0 2, 0 – 3,0 3,0 – 4,0
4 type: < 2
2,0 – 3,0 3,0 – 4,0
6 type: < 1,8
1,8 ‐ 2,8 2,8 ‐ 3,8
4 type: <0,06
0,06 – 0,09 0,090 – 0,135
6 type:<0,045 0,045– 0,09 0,090 – 0,135
5
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Regarding biological elements then comparability is not possible neither by assessment of fish fauna, macroinvertebrates, macrophytes or phytobenthos (diatoms). A.3.2. Comparison of the existing classification of lake water bodies
As there is only one transboundary lake water body between Latvia and Estonia the established quality classification system is presented for the lake Murati. Latvian system for main biological elements is still in the development process; therefore Estonian values were applied during the project to cover this gap. Regarding physico‐chemical quality indicators, the present boundaries between high and good as well as good and moderate are realatively closed. Nevertheless, harmonisation and setting common boundaries based on one year measurements would not be scientifically sound. Table A.3.3. Ecological status classification of type II lakes in Estonia (including the lake Murati7) ( VST – submerged plants; ULT – floating leaved plants, UT – floating plants) Quality indicator Unit
High
Good
Moderate
Quality element: phytoplankton (arithmetic mean of analysis results)
Chlorophyll a content of the water column (average of three limnological layers) micrograms/l <10 10–20 >20–30 Chlorophyll a content in surface layer (depth 0,5 m ) micrograms/l <10,8 10,8–28 >28–52 Phytoplankton community ‐ Phytoplankton compound quotient (FKI) ‐ <3,5
3,5–6
>6–9
Pielou uniformity index J (Evenness) Scale 0–1
>0,8
>0,6–0,8 >0,4–0,6
Abundance of Abundance of species 3‐5 species are species is more or is more or less equal, dominating by less equal, certain certain dominants abundance (>80%)
dominants cannot cannot be be distinguished distinguished Quality element: macrophytes Plant community (= meaning More important Bryophyta, codomincance or alternative) taxons of Charophyta, hydrophytes by Potamogeton turns of abundance in whole lake; in case of higher taxons species summed up Relative abundance of Potamogeton perfoliatus or group P.lucens in VST Braun‐Blanquet
scale (0–5). In case of both – assessment of more abound one Charophyta= Potamogeton , Bryophyta = Elodea = Myriophyllum = Ceratophyllum ≥4
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Ceratophyllum = Ranunculus = Myriophyllum= Potamogeton= Charophyta 1 Quality indicator Relative abundance of Charophyta or moss taxa in VST group Unit
High
Good
Moderate
Braun‐Blanquet
scale (0–5). In case of several – assessment of most abound 3
4–5
2 Abundance of Ceratophyllum Braun‐Blanquet
or lemnids in VST or ULT & UT scale (0–5). In case groups of several – assessment of most abound 0
1–2
3 Abundance of large (also scale 0–5 epiphytic) filamentous green algae 0
1
1‐2
Quality element: macroinvertabrates (arithmetic mean of analysis results)
Macroinvertabrates number of taxa ‐ >32 (flora)
>24 (sand and stones) 32–28 (flora)
24–22 (sand and stones) Macroinvertabrates number of sensitive taxa (EPT) ‐ >8 (sand and stones) >5 (flora) 8–7 (sand and stones) 6–5 (sand and 5 (flora) stones) 4 (flora) Macroinvertabrates Shannon diversity index (H) ‐ >2,8 (flora)
>1,7 (sand) >2,4 (stones) 2,8–2,4 (flora)
1,7–1,5 (sand) 2,4–2,1 (stones) <2,4–1,8 (flora)
<1,5–1,1 (sand) <2,1–1,6 (stones) Macroinvertabrates ASPT (taxon’s average sensitivity) ‐ >5,1 (flora and sand) >5,7 (stones) 5,1–4,5 (flora and sand) 5,7–5,1 (stones) <4,5–3,4 (flora and sand) <5,1–3,8 (stones) Macroinvertabrates acidity index (A) ‐ >6 (flora and sand) >7 (stones) 6 (flora and sand) 7–6 (stones) 5–4 (flora and sand) 5 (stones) 27–21 (flora)
21–16 (sand and stones) Physico‐chemical quality indicators pH pH unit 7–8
>8–8,3
>8,3–8,8
Total phosporus (Ptot) Micrograms P /l
<30
30–60
>60–80
Total nitrogen (Ntot) Micrograms N/l
<500
500–1000 >1000–1500
>3
2–3
1–<2
Transparency by Secchi disc m Table A.3.4. Ecological status classification of type VI lakes in Latvia (Murati) Quality indicator Unit High
Quality element: phytoplankton (arithmetic mean of analysis results)
Chlorophyll a content of the Migrograms per l
<7 upper part of water column Phytoplankton biomass Mg/l <1 Quality element: Physico‐chemical quality indicators
Total phosporus (Ptot) Micrograms P/l
<30 Total nitrogen (Ntot) Transparency by Secchi disc
Micrograms N/l
<800 m Good 7‐12 12‐40 1‐2,5
2,5‐5,0 30‐55
55‐80 800‐1300
1300‐1800
Not relevant for this type* * For polyhumic lakes the transparency is not connected with ecological status 20 Moderate A.3.3. Comparison of the existing classification of coastal waters
Few biological quality elements are recommended as parameters to assess ecological status of the water bodies in the Gulf of Riga in both countries Latvia and Estonia – concentration of chlorophyll a, depth limit of macroalgal community and depth limit of key species Fucus vesiculosus. Table A.3.3.a. shows the comparison between ecological criteria values recommended by both countries. Table A.3.3.a. Ecological status criteria values of physico‐chemical quality elements for the Gulf of Riga, East coast8, the Regulation of the Minister of the Environment9 for Estonian coastal water type VI. high
good moderate
Country
units
Biological quality elements Concentration of chlorophyll a Depth limit of macroalgal community Depth limit of Fucus vesiculosus Latvia Estonia Latvia Estonia Latvia10 Estonia μg/m3
μg/m3
m
m
m
m
‐
<2.4
>11
>9.6
>10
>4
2.7 2.4‐3 10‐11 6.0‐9.6 6‐10 4‐2.5 ‐ 3‐6.2
‐ 3.6‐<6.0
‐ <2.5‐1.5
Both countries use concentration of chlorophyll a as biological quality element, although Estonians have set more detailed criteria values for this indicator, while Latvians have only Good‐Environmental‐Status or GES boundary (between good and moderate status). Concentration of chlorophyll a is easy measurable and precise parameter and it should be developed into indicator that could be used in the Gulf of Riga in both countries. Parameter “depth limit of macroalgal community” has similar values of high ecological status in both countries, while the boundaries of good status are considerably different. To develop this indicator for the Gulf of Riga further, they should be analyzed and discussed more, as well as boundary values for moderate, bad and poor ecological status should be set for Latvian waters. Depth limit indicator of F. vesiculosus has very different values both for class boundaries and reference conditions and more effort should be dedicated for the indicator development in Latvia and harmonization between two involved countries. Three physico‐chemical quality elements are recommended as parameters to assess ecological status of the Gulf of Riga in Latvia and in Estonia – water transparency during summer and winter concentration of total nitrogen and total phosphorus. Criteria values for each parameter and for each country are shown in Table A.3.3. b. 8
DANCEE project No M: 128/023‐004 “Transposition and Implementation of the EU Water Framework Directive in Latvia”, 2004. Technical Report No. 1B “Classification and presentation of status of waters”, 56 p., [http://www.varam.gov.lv/eng/projekti/es_vides_projekti/?doc=3315]. 9
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DANCEE project No M: 128/023‐004 “Transposition and Implementation of the EU Water Framework Directive in Latvia”, 2004. Technical Report No. 1B “Classification and presentation of status of waters”, 56 p., [http://www.varam.gov.lv/eng/projekti/es_vides_projekti/?doc=3315]. 21 Table A.3.3.b. Ecological status criteria values of physico‐chemical quality elements for the Gulf of Riga, East coast11 and by the Regulation of the Minister of the Environment for Estonian coastal water type VI12. Physico‐chemical Country units season high good moderate quality elements Transparency Total nitrogen Total phosphorus Latvia Estonia Latvia Estonia Latvia Estonia m m μmol/l
μmol/l
μmol/l
μmol/l
summer
summer
winter
winter
winter
winter
>4.5
>4.9
<11
<19.2
<0.7
<0.40
3.5‐4.5
4.9‐4.2
11‐19
19.2‐23.7
0.7‐1.0
0.40–0.50
‐ 4.2‐2.6 ‐ 23.7‐48.2 ‐ >0.50–1.0 Water transparency in summer and winter concentration of total phosphorus could be developed as indicators to assess ecological status of the Gulf of Riga, because criteria values used in Latvia and Estonia are similar, while criteria values of winter concentration of total nitrogen differs considerably and without further studies and cooperation between both countries this parameter cannot be developed into indicator showing ecological status of the Gulf of Riga. 11
DANCEE project No M: 128/023‐004 “Transposition and Implementation of the EU Water Framework Directive in Latvia”, 2004. Technical Report No. 1B “Classification and presentation of status of waters”, 56 p., [http://www.varam.gov.lv/eng/projekti/es_vides_projekti/?doc=3315]. 12
https://www.riigiteataja.ee/aktilisa/1251/1201/0015/KKM59_lisa6.pdf# 22 B. Methodology overview B.1. Sampling, treatment and class boundaries for ecological status assessment in rivers In the frame of the Gauja/Koiva project the ecological status of rivers was assessed according to physico‐
chemical and biological quality elements: benthic diatoms, macroinvertbrates, aquatic macrophytes, and fish. Physico‐chemical quality elements were investigated in two ways:  single sampling in summer season in the same time and site where biological quality elements were sampled;  monthly sampling independently from biological quality elements only in Estonian rivers by Estonian experts. B.1.1. Benthic diatoms (phytobenthos)
57 benthic diatom samples (24 in Estonia, 33 in Latvia) were taken in total. In 6 sites (3 in Estonia and 3 in Latvia) joint samplings were carried out by Estonian and Latvian experts (locations of joint sampling sites see Figure C.1.a). The aim was to test the Estonian approach, learn their experience and harmonise sampling in practice since none of Latvian experts had experience to sample benthic diatoms before this project. In both Latvia and Estonia diatoms were sampled accordingly to the following European Union standards:  CEN (2003) ‐ Water quality – Guidance standard for the routine sampling and pre‐treatment of benthic diatoms from rivers. EN 13946: 2003. Comité European de Normalisation, Geneva.  CEN (2004) ‐ Water quality ‐ Guidance standard for the identification, enumeration and interpretation of benthic diatom samples from running waters. EN 14407:2004. Comité European de Normalisation, Geneva. Samples of benthic diatoms were collected from small stones. One sample consisted of diatoms from at least five different stones, which have been picked up perpendicularly to the current flow. The maximum depth of water where stones were picked is 0.5 m. Diatoms were removed from stones by rubbing them with a toothbrush and fixed using ethanol (70%). At the laboratory the samples were treated with HCl and H2SO4 to remove the organic matter. Then the samples were washed repeatedly with distilled water to remove the acid. The resulting suspension contained pure diatom valves and it was treated with resin ‘Naphrax’ to make slides. From every sample the systematic belonging of at least 400 diatom cells was determined. Taxon with relative abundance >25% was considered as dominant taxon, taxon with relative abundance >10% was considered to be subdominant (abundant). The ecological status of the river was assessed using three diatom indexes: - IPS – Indice Polluosensitivité Spécifique (Specific Polluosensitivity Index)13; 13
Coste in CEMAGREF, (1982). Etude des méthodes biologiques d'appréciation quantitative de la qualité des eaux. Rapport Q.E. Lyon A.F. Bassin Rhône‐Méditérannée‐Corse, 218 p. 23 - WAT – Watanabe Index14; - TDI – Trophic Diatom Index15. The indexes were calculated using the latest version of ‘OMNIDIA’ software16, which takes into account the species composition, the relative abundance of species, and the sensitivity to pollution of different species. The software calculates the diatom indexes IPS and WAT within the scale 1‐20, and TDI index within the scale 1‐100. The first two indexes correlate positively with the ecological state of the water body (higher values indicate better state), the TDI index correlates negatively with the ecological state (lower values indicate better state). To avoid misunderstanding the TDI index was recalculated: 100‐TDI. Diatom indexes are indifferent to type of river water body. “The intercalibration typology proved unhelpful because it is unable to differentiate between the diatom assemblage found at reference conditions”17. Primary pressure responsible for the deviations of benthic diatom assemblages from the reference assemblages is nutrients and/or organic pollution and they are not sensitive to other pressures (e.g. hydromorphological deviation of water body, toxic pollutants). They respond to the eutrophication as a stress factor and thus it is possible to assess the ecological state of water body. Usually the values of diatom indexes reflect neither the size nor the hydromorphological state of the river. The ecological state of the river water bodies are assessed according to Estonian quality class boundaries adopted by the regulation of the Minister of the Environment18 in both countries (showed in Tale B.1.1.) since in Latvian no class boundaries for benthic diatoms are developed yet. The established class boundaries are not type specific, e.g., the same value are used for all type of water bodies. Table B.1.1. Class boundaries for the indexes used in benthic diatoms assessment Indexes High Good Moderate Poor Bad IPS >15.5 15.5‐>12.0 12.0–>9.5 9.5–6.9 <6.9 WAT >15.9
15.9–>12.4
12.4–>9.7
9.7–7.1
<7.1 TDI <48 48‐<61 61‐<75 75‐<87 87‐100 >52 52‐>39 39‐>25 25‐>13 <13 100‐TDI Assessment of the ecological status of river water bodies according to the benthic diatoms is given as an average of the state results of three used indexes (see chapter C.2.1.1). 14
Watanabe,T., Asai, K., Houki, A. (1990). Numerical simulation of organic pollution in flowing waters. Encyclopedia of Environmental Control Technology, 4. Hazardous Waste Containment and Treatment. (Cheremisinoff, P.N., ed.). Houston: Gulf Publishing Company, 251‐284. 15
Kelly, M.G., Whitton, B. A. (1995). A new diatom index for monitoring eutrophication in rivers. – Journal of Applyed Phycology, 7, 433‐444. 16
Lecointe C., Coste M. & Prygel J., (1993). “Omnidia” software for taxonomy, calculation of diatom indices and inventories management. – Hydrobiologia, 269/270: 509‐513. 17
Kelly, M., Bennett, C., Coste, M., Delmas, F., Denys, L., Ector, L., Fauville, C., Ferreol, M., Golub, M., Jarlman, A., Kahlert, M., Lucey, J., Ni Chathain, B., Pardo, I., Pfister, P., Picinska‐Faltynowicz, J., Schranz, C., Schaumburg, J., Tison, J., Van Dam, H., Vilbaste, S. 2009. A comparison of national approaches to setting ecological status boundaries in phytobenthos assessment for the European Water Framework Directive: results of an intercalibration exercise. Hydrobiologia, 621, 169‐182.
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In total, 72 macroinvertebrate samples (25 in Estonia and 59 in Latvia) were taken in the frame of the Gauja/Koiva project. In 8 sites (4 in Estonia and 4 in Latvia) joint samplings were carried out by Estonian and Latvian experts to compare and harmonise sampling in practice (location of joint sampling sites see Figure C.1.a.). Joint samplings were carried out in May, 2012. The sampling was performed according to the following methods:  Swedish method19 used by Estonian expert;  Danish method20 used by Latvian expert in 49 sampling site (including joint sampling sites);  Modified AQEM21 multi‐habitat sampling method used by Latvian expert in 7 sampling sites additionally to the Danish method;  Ekman grab used by Latvian experts in 2 sampling sites in the river Salaca. Swedish method (Medin et al. 2001). Each sample consisted of five 1 m long kick or sweep replications by standard handnet with 0.5 mm mesh size (European…, 1994). The replications were taken from typical similar bottom from the lower part of sampling area. Each sample covered 0.25 m2 of the most typical substrate, complemented by a separate qualitative sample from all shallow‐water bottom types at the same site. Sweeping was used at the sites where bottom was too soft to stand on. Standard sample size (1.25 m2 plus qualitative sample) exceeded the area required to represent all important macroinvertebrate taxa in the littoral (according to Schreiber & Brauns 2010). According to Lorenz et al. (2004), a certainty <20% to classify a sample into wrong quality class is obtained with a sample size at least 300 individuals in lowland streams. Sampled animals were fixed in 96% ethanol in the field, together with debris. Danish method (Skriver et al. 2000). Sampling was undertaken using hand‐net with a 0.25 x 0.25 m opening and net‐bag with a mesh size of 0.5 mm. Sampling was carried out at three transects across the stream lying about 10 m apart, four kick samples were taken at each transect 25%, 50%, 75% and 100% starting from one of the stream banks. When the stream width was less than one meter, i.e. the stream width of four hand‐net heads (e.g. Kāršupīte), transects were placed diagonally in an upstream direction (Figure B.1.2.a). Sampling was started at the downstream transect and continued upstream (Skriver et al. 2000). The 12 kick samples were pooled for further analysis. The kick samples were collected by placing the hand‐net on the stream bed, and then placing a foot on the stream bed in front of the hand‐net, with the toes pointing downstream. The foot was then moved backwards about 40 cm against the current. Kick sampling was supplemented by 5 minutes of hand‐picking from submerged stones and large wooden debris8. Samples were preserved in the formaldehyde solution (4% final concentration). 19
Medin M., Ericsson U., Nilsson C., Sundberg I., Nilsson P.‐A., 2001. Bedömningsgrunder för bottenfaunaundersökningar. Medins Sjö‐ och Åbiologi AB. Mölnlycke, 12 pp. 20
Skriver J., Friberg N., Kirkegaard J., 2000. Biological assessment of watercourse quality in Denmark: Introduction of the Danish Stream Fauna Index (DSFI) as the official biomonitoring method. ‐ Verh. Internat. Verein. Limnol. 27: 1822‐1830. 21
STAR site protocol 2010. (http://www.eu‐star.at/frameset.htm) (visited 2011‐07‐14). 25 Modified AQEM “multi habitat sampling” method. Samples were taken using Surber sampler with a 0.25 x 0.25 m opening and 0.25 x 0.25 m sampling frame. The net‐bag mesh size was 0.5 mm. Before the sampling, the STAR project site protocol was completed. The coverage of all microhabitats was evaluated in the 100 m stream reach. Cover was recorded to the nearest 5% interval, the presence of other microhabitats (<5% cover) was only indicated. We sampled macroinvertebrates only from the microhabitats with the cover 10%. Sampling was started at the downstream end of the 100 m reach and preceded upstream. We have taken only 10 sampling units instead of the originally provided 20 sampling units for the AQEM sampling method22 (Figure B.1.2.). 10 sampling units were distributed according to the share of the microhabitats. Total sampling area was 0.625 m2. Samples were preserved in the formaldehyde solution (4% final concentration). Figure B.1.2.a Danish sampling methodology at Figure B.1.2.b Example of sampling unit position in three transects (according to Skriver et al. 20008). atheoretical sampling site according to the “multi‐
habitat sampling” method applied in AQEM (according to AQEM Consortium 20029). Ekman grab. Samples in Salaca River at two upper deep potamal type reaches were taken from boat using Ekman grab sampler in area 0.2 x 0.2 m. Ekman grab sampler were of standard size. Sorting, counting and identification were done in the laboratory. To characterize biological quality on the basis of macroinvertebrates, five commonly used indices were calculated for each sampling site in both countries:  Total taxon richness T (taxa identified according to Johnson´s list23, modified for local conditions),  Shannon diversity H´,  sensitive (Ephemeroptera, Plecoptera and Trichoptera) taxon richness EPT24,  Average Score Per Taxon ASPT25,  Danish Stream Fauna Index DSFI18. 22
AQEM Consortium, 2002. Manual for the application of the AQEM system. A comprehensive method to assess European streams using benthic macroinvertebrates, developed for the purpose of the Water Framework Directive. Version 1.0, February 2002. 23
Johnson R.K., 1999. Benthic macroinvertebrates. In: Bedömningsgrunder för miljökvalitet. Sjöar och vattendrag. Bakgrundsrapport 2. Biologiska parametrar (Ed. by Torgny Wiederholm). Naturvårdsverket Förlag, 85‐166. 24
Lenat D.R., 1988. Water quality assessment of streams using a qualitative collection method for benthic macroinvertebrates. ‐ Journal of North American Benthological Society 7: 222‐233. 25
Armitage P.D., Moss D., Wright J.F., Furse M.T., 1983. The performance of a new biological water quality score system based on a wide range of unpolluted running‐water sites. ‐ Water Research 17: 333‐347. 26 Benthic macroinvertebrates were identified to the best possible, lower taxonomic level (species level). Chironomidae, Simuliidae, Hydrachnidia, Nematoda were not identified further. Other Diptera, Coleoptera, Heteroptera, Lepidoptera taxa were mostly identified to the family or genus level. Also Oligochaeta were identified mostly to the species level. Before the calculation of metrics a taxonomical adjustment was applied to avoid the overlapping of taxa. Most metrics were calculated on the basis of the whole compound sample (five replications plus one qualitative sample), only H´ was calculated on the basis of five replications only. The values of all used indices were considered proportional with biological quality. Multimetric approach has preferences over single‐metric approach, as different indices outline different stress types15 26.The total taxon richness characterizes total biodiversity. Shannon diversity depends both on taxon richness and their levels of domination. ASPT is mean sensitivity of taxon, and EPT is the number of sensitive taxa. DSFI estimates level of organic pollution. The reference values in Estonia and class boundaries for all indices in all river types and subtypes are presented in the Table B.1.2. Latvian experts used the same reference values and class boundaries, because assessment method used in the project is new for Latvian experts and Latvia has not developed own class boundaries yet. Table B.1.2. Reference values and class boundaries for benthic macroinvertebrates in rivers taking into account size of catchment area, velocity of flow and type of bedrock Metric Catchment area (km2), flow R* velocity and bedrock type High Good Moderate Poor or Bad T <100, fast 29 >26 23‐26 17‐22 <17 T T <100, slow 100‐1000, fast 18 35 >16 >32 14‐16 28‐32 11‐13 21‐27 <11 <21 T T EPT EPT 100‐1000, slow >1000 <100, fast <100, slow 29 33,5 13 9 >26 >30 >12 >8 23‐26 27‐30 10‐12 7‐8 17‐22 20‐26 8‐9 5‐6 <17 <20 <8 <5 EPT H´ >100 <100, limestone 16,5 2,4 >15 >2,1 13‐15 1,9‐2,1 10‐12 <1,9‐1,4 <10 <1,4 H´ ASPT <100, sandstone; and >100 3 <100, slow 6,1 >2,7 >5,5 2,4‐2,7 4,9‐5,5 <2,4‐1,8 <4,9‐3,7 <1,8 <3,7 ASPT ASPT <100, fast >100 6,6 6,9 >5,9 >6,2 5,3‐5,9 5,5‐6,2 <5,3‐4 <5,5‐4,1 <4 <4,1 DSFI 7 6‐7 5 4 <4 * mean reference value 26
Status classes and class boundaries for surface waterbodies and the procedure of classification, 2009 (in Estonian). Regulation project of the Ministry of the Environment of Estonia. Available at: <https://www.riigiteataja.ee/ert/act.jsp?id=13210253& replstring=33> (9.02.2011). 27 For determination of ecological status according to macroinvertebrates Estonian multimetric method was used because Latvia has not developed its own method. All values of high quality were assigned five points, values of good quality ‐ four points, values of moderate quality ‐ two points, and values of poor and bad quality ‐ zero points. The difference between good level and moderate level was intentionally emphasized in order to underline the principal difference between them in terms of the Water Framework Directive. Multimetric quality (MMQ) was then calculated by adding up the corresponding points. Hence, the reference value was 25 and the sum 23−25 was considered to indicate high, 18−22, good, 10−17, moderate, 6−9, poor and <6, bad ecological status of the river water body. B.1.3. Macrophytes
The status of rivers according to macrophytes was assessed in 72 sites (23 in Estonia and 49 in Latvia). In 6 sites the joint fieldworks were carried out to compare and harmonise sampling in practice. Locations of joint sampling sites are showed in Figure C.1.a. Slight modification of the Polish river assessment method27 was used for macrophytes assessment by experts from both countries. The method is adjusted according to Estonian conditions and it was overtaken also by Latvian experts. During the fieldwork every species that was noticed in 100 m river site „with a naked eye“ were recorded. The coverage value is given to every species in 9‐point scale (Table B.1.3.a). Table B.1.3.a. Coverage value in 9‐point scale Coverage <0,1% 0,1‐1% 1‐2,5% 2,5‐5% 5‐10% 10‐25% 25‐50% 50‐75% >75% Coverage 1 2 3 4 5 6 7 8 9 value The status of the rivers is assessed using MIR index (Polish Macrophyte River Index) and 93 indicative species (Table B.1.3.b). Every indicative species is given two scores: 1. Trophic ranking score from 1 (for hypertrophy) to 10 (for oligotrophy); 2. Weight value from 1 for species with broad range of tolerance (eurytopic) to 3 for species with very narrow range of tolerance (stenotopic). MIR value is calculated: MIR 
 Li  Wi  Pi  10 Wi  Pi
Where: L – trophic ranking score W – weight value P – coverage Szoszkiewicz, K., Zbierska, J., Jusik, S., Zgoła, T. (2010). Macrofitowa Metoda Oceny Rzek. Poznan: Bogucki Wydawnictwo 27
Naukowe, 82 lk.
28 Table B.1.3.b. Macrophyte indicator species Species Algae Batrachospermum spp. Chara fragilis Cladophora spp. Enteromorpha spp. Heribaudiella fluviatilis Hildenbrandia rivularis Phormidium spp. Spirogyra spp. Ulothrix spp. Vaucheria spp. Oedogonium spp. Rhizoclonium spp. Mosses Amplystegium riparium Fontinalis antipyretica Rhynchostegium riparioides Horsetails Equisetum fluviatile Monocotyledones Acorus calamus Agrostis stolonifera Alisma lanceolatum Alisma plantago‐aquatica Alopecurus geniculatus Butomus umbellatus Carex acuta Carex acutiformis Carex riparia Carex rostrata Carex vesicaria Catabrosa aquatic Eleocharis palustris Elodea Canadensis Glyceria fluitans Glyceria maxima Glyceria plicata Hydrocharis morsus‐ranae Iris pseudacorus Juncus articulatus Lemna gibba L
6
6
1
1
5
6
2
2
4
2
1
1
1
6
5
6
2
5
4
4
4
5
5
4
4
6
6
5
6
5
5
3
5
6
6
8
1
MIR W 2 3 1 3 2 2 1 2 1 1 3 3 2 1 2 1 2 2 3 1 3 1 1 2 3 2 2 2 3 2 2 1 1 2 1 3 3 Species Lemna minor Lemna trisulca
Phalaris arundinacea
Phragmites australis
Potamogeton alpinus
Potamogeton crispus
Potamogeton friesii
Potamogeton gramineus
Potamogeton lucens
Potamogeton meinshusenii
Potamogeton natans
Potamogeton pectinatus
Potamogeton perfoliatus
Sagittaria sagittifolia
Schoenoplectus lacustris
Scirpus sylvaticus
Sparganium emersum
Sparganium erectum
Sparganium microcarpum
Spirodela polyrhiza
Stratoites aloides
Typha angustifolia
Typha latifolia
Dicotyledones
Berula erecta
Calla palustris
Caltha palustris
Ceratophyllum demersum
Cardamine amara
Cicuta virosa
Eupatorium cannabinum
Hippuris vulgaris
Naumburgia thyrsiflora
Lysimachia vulgaris
Mentha aquatica
Mentha x verticillata
Menyanthes trifoliata
Myosotis scorpioides
Myriophyllum spicatum
Nuphar lutea
Nymphaea alba
MIR
L
2
4
2
4
7
4
3
7
4
6
4
1
4
4
4
5
4
3
3
2
6
3
2
W
1
2
1
1
2
2
3
3
2
3
2
2
2
2
2
2
2
1
2
2
3
3
2
4
6
6
2
4
6
3
4
7
4
5
4
9
4
3
4
6
2
2
1
3
3
2
2
2
2
2
2
2
3
1
2
1
2
Species Oenanthe aquatica Polygonum amphibium Polygonum persicaria Ranunculus circinatus Ranunculus lingua Ranunculus sceleratus Ranunculus trichophyllus
Rorippa amphibia Rumex aquaticus Rumex hydrolapathum Sium latifolium Solanum dulcamara Stachys palustris Utricularia vulgaris Veronica anagallis‐aquatica
Veronica beccabunga L
5
4
2
5
8
2
6
3
3
4
7
3
2
5
4
4
MIR
W
1
3
3
2
2
2
2
2
2
2
1
2
2
3
1
2
MIR values for ecological status class boundaries for Estonian river types are given in Table B.1.3.c. Class boundaries for two larger river types of Estonia is still missing, because there is not enough data yet. Latvian experts used the Estonian river typology and defined class boundaries for Latvian river water bodies. 29 Table B.1.3.c. MIR values for ecological status class boundaries for Estonian rivers River types 1A 1B 2A 2B 3A 3B 4B HIGH GOOD MODERATE POOR BAD ≥42,2 ≥37,8 ≥39 ≥37,9 ≥35,6 ≥37,2 ≥35,3 30,5‐42,1 27,3‐37,7 28,1‐38,9 27,4‐37,8 25,7‐35,5 26,8‐37,1 25,5‐35,2 18,8‐30,4 16,8‐27,2 17,3‐28 16,8‐27,3 15,8‐25,6 16,5‐26,7 15,7‐25,4 7‐18,7 6,3‐16,7 6,5‐17,2 6,3‐16,7 5,9‐15,7 6,2‐16,4 5,9‐15,6 <7 <6,3 <6,5 <6,3 <5,9 <6,2 <5,9 6,4‐16,9 <6,4 ≥38,3 27,6‐38,2 17‐27,5 HMWB* *HMWB – heavily modified water body B.1.4. Fish
In total, in 70 sampling sites (19 in Estonia and 51 in Latvia) fish samples were collected during July and August in 2011 and 2012. In both countries samples were collected using electrofishing gears. Fish samples were not collected jointly because of legal obstacles, but experts exchanged experience and participated as observers during sampling in neighbouring countries. Sampling methods between countries are different. In Estonia rhitral river sections were preferred and the length of the electrofished area was 80‐ 200 m. When possible, whole sampling area is electrofished. In some cases (larger rivers, special or different habitats, rich vegetation), “partial” electrofishing method were used. In that case, the time limit at least 40 minutes in case of small streams (<100 km2) and 60 minutes in case of larger streams (>100 km2) is followed. In Latvia three‐pass and single‐pass electrofishing methods were used. In Estonia species composition, abundance and age structure of species is determined for sampled fish. All fish are counted by species in 3 age classes: 0+ (YOY), 1+ (two summer old), >1+ (older specimen). In Latvia the abundance, density (ind./100 m2) and biomass (kg/100 m2) of fish were calculated. Fish biomass was calculated as the number of fish multiplied by the average weight of a fish for every species. Only fish with a length >50 mm were included in density and biomass calculations. The abundance of fish was calculated in two ways. At the sites where three‐pass electrofishing was conducted, fish abundance was estimated using the method of three removals. At the sites where single‐pass sampling was used, the theoretical number of fishes was calculated from the number of fishes caught in the first electrofishing pass and fish catchability (p). The latter (p) was estimated for each species separately from the pooled results of three electrofishing passes28. In Estonia status of fish fauna is estimated by means of comparison of reference conditions to electrofishing results. Initial reference fish communities (lists of indicator and type specific species) are found according to “Typology of fish communities of Estonian streams”. 28
Bohlin T., Hamrin S., Heggberget G.T., Rasmussen G., Saltveit J.S. 1989. Electrofishing‐ theory and practice with special emphasis on salmonids. Hydrobiologia, 173: 9‐ 43. 30 The status of fish fauna is calculated using the following formula: S = (2*I1 + I2 – I3 – 2*I4 + T1 + T2/2 – T3/2 – T4) / (L1 + L2), Where: I1 ‐ number of indicator species recorded in the electrofishing, abundance and age structure of the species corresponded to the natural habitat quality; I2 ‐ number of indicator species recorded in the electrofishing, abundance and age structure of the species did not correspond to the natural habitat quality; I3 ‐ number of indicator species absent (but not extinct in the present river or river section); I4 ‐ number of indicator species absent (extinct or probably extinct in the present river or river section); T1 ‐ number of type specific species recorded in the electrofishing, abundance and age structure of the species corresponded to the natural habitat quality; T2 ‐ number of type specific species recorded in the electrofishing, abundance and age structure of the species did not correspond to the natural habitat quality; T3 ‐ number of type specific species absent (but not extinct in the present river or river section); T4 ‐ number of type specific species absent (extinct or probably extinct in the present river or river section); L1 ‐ number of indicator species according to the reference conditions; L2 ‐ number of type specific species according to the reference conditions; Class boundaries of the index S are the same in all river types (class boundaries see in table B.1.3.d.). In Latvia, fish assessment was based on index FIBS (fish based assessment system). FIBS considers several ecological attributes of fish communities by implementing 6 fish‐ecological quality features referring to the terms given by the WFD, namely “species composition”, “species abundance” and “age structure”. All metrics used are solely based on proportions (percentages) of single species, 0+ age classes or ecological guilds. Neither absolute abundances (related to areas or stretches) nor biomasses are used in FIBS. The score of each metric result from a comparison of the metric's value calculated from the sampling result with the corresponding value calculated from the reconstructed reference fish community. Fish sampling data must fulfil the following minimum quality criteria:  all fish species must be counted separately,  0+ age class (estimated from fish size during sampling) and older individuals of each species have to be counted separately,  the total number of individual fish sampled should not drop significantly below the 30‐fold of the number of species of the reference fish community and  the fish community has to be sampled in adequate river stretches depending on river size and river type. Table B.1.4. Class boundaries for S and FIB indecies Class boundaries for indexes High Good S ≥ 0,8 0.79 ‐ 0.4 FIBS 3.76‐ 5.00 2.51‐ 3.75 31 Moderate
0.39 ‐ 0 Poor < 0 2.01‐ 2.50 1.51‐ 2.00 Bad fish are absent 1.00‐ 1.50 B.1.5. Physico-chemical quality elements
In total, in 57 sites (21 in Estonia and 46 in Latvia) assessment water quality according to physico‐
chemical quality elements were investigated. Samplings were carried out in the same time (in summer 2011 and 2012) and sampling sites where sampling of biological quality elements was carried out. Monthly sampling independently from biological quality elements were carried out in 13 sites in Estonia. 8 of sampling sites are located in transboundary water bodies: Pedetsi/Pededze (Kivioja), Pedetsi/Pededze (Möldre), Vaidava (outlet from Lake Murati/Muratu), Vaidava (Kuutsi), Peetri/Melnupe (Leppura), Pärlijõgi/Pērļupīte, Pedeli/Pedele (Valga), Pedeli/Pedele (Koorküla). Physico‐chemical quality elements were assessed according to Latvian and Estonian national legislations and RBMP partly described already in chapter A.3.1. Quality elements used in both countries are: dissolved oxygen, biochemical oxygen demand, ammonium, total nitrogen, total phosphorus and pH. In the frame of the project, assessment of the ecological status according to physico‐chemical quality elements was evaluated using different approaches by Latvian and Estonian experts. Latvian experts for assessment of ecological status used samples collected in the same time when biological quality elements were sampled. But Estonian experts took them into account only for interpretation of the results. The overall assessment of the ecological status according to physico‐chemical water quality was based on expert judgement, although Latvian legislation requires the principle “one out – all out”. In Estonia status assessment were based on scoring system described in Estonian national legislation using 1 year monthy sampling results. If pH value were between 6 and 9, the overall rating was a sum of each indicator (pH excluded) points from 1‐5 as follows: 5 – high, 4 – good, 3 – moderate, 2 – poor, 1 – bad. Maximum score was 25. If pH value was lower than 6 or higher than 9, the overall rating was bad, irrespective of other indicators values. Ecological status was high if score is between 23 and 25, good 18‐
22, moderate 13‐17, poor 8‐12 and bad if score is below 8. 32 B.2. Sampling, treatment and class boundaries for ecological status assessment in lakes The assessment of ecological status in lakes was based on quality of water physico‐chemical quality elements and biological elements: phytoplankton, benthic macroinvertbrates, macrophytes and fish (only in Estonia). In Estonia quality of hydromorphology were assessed and used also as one of parameter assessing ecological status in lakes. Sampling of water physico‐chemical quality elements are not described in this report, because in frame of the project water sampling for the assessment of ecological status was not compared between experts. Class boundaries of the physico‐chemical quality elements were compared already in chapter A.3.2. B.2.1. Phytoplankton
In total 14 lakes were sampled (9 in Estonia, 2 in Latvia, 3 transboundary lakes) to assess ecological status of water bodies according to phytoplankton. Joint fieldworks were carried out in all three transboundary lakes (Lake Kikkajärv/Ilgājs, Lake Murati/Muratu and Lake Väike Palkna/Mazais Baltiņš (location of tranboundary lakes see in Figure C.1.a), three times during growing season in May, July and September 2012. During May sampling activity, both expert teams implemented Estonian method, but other two times the experts collected samples according to national practice. In May: three layers of water column were used in the stratified lakes, in polymictic layers depending on depth, one or two layers. Quantitative samples were collected on a lake from the deepest location by van Dorn sampler. Apstein plankton (mesh size 10, 20 μm) net was used for qualitative sampling by trawling. For counting procedure Utermöhl’s technique was used, which is at the same time the European standard. In other two times, Latvian experts collected samples by Ruttner type water sampler different water layers. Phytoplankton samples were generally fixed by lughole solution. For determination, counting and measurement of the phytoplankton the Utermöhl method29 30was used, which is at the same time European standard. For determination of ecological status of the phytoplankton Estonian multimetric method was used because Latvia has not developed its own method. Four parameters were used to assess the ecological status of the phytoplankton: 1. Chlorophyll a (Chl a) according to Jeffery & Humphrey 31 2. Evenness (J) ‐ modified Pielou index. The range of values is between 0‐ 1. The scale is divided equally into five classes in each lake type. The basis of that index is the idea that the abundance of species is equally distriubuted in climax communities. A climax community has a high ecological status. In fact equation is calculated from Shannon’s diversity (H). Another component of the equation is theoretical diversity (Hmax). The latter is calculated if considered that the abundance (or biomass) is equally divided with concrete number of species in sample. Equation: J = H/Hmax. The higher value, the 29
Utermöhl, H. (1958) Zur Vervollkommnung der quantitativen Phytoplankton‐Methodik. Mitt int. Verein. theor. angew. Lim¬nol. 9: 1‐38 30
Tikkanen, T, Willén, E. (1992) Växtplanktonflora. Naturvårdsverket. ISBN 91‐620‐1115‐4. pp. 280 31
Jeffery, S.W. and Humphrey, G.F. (1975). New spectrophotometric equations for determining chlorophylls a, b, c1, and c2 in higher plants, algae and natural phytoplankton. Biochem. Physiol. Pflanz. 167: 191‐194. 33 better ecological status. Class boundaries for J index are the same in all lake types as following: 0.81‐1 high; 0.61‐0.80 good; 0.41‐0.6 moderate; 0.21‐0.4 poor; 0‐0.20 bad status. 3. Nygaard’s modified compound quotient (PCQ/FKI) 32 ‐ the modified Nygaard’s phytoplankton compound quotient is used to characterize the ecological status of the lake. PCQ gives a quite good estimation of the lakes’ ecological condition, although algal groups in formula may contain species with different preferences. Ott & Laugaste 33 added to the original formula two extra taxa: Cryptophyta to the numerator and Chrysophyceae to the denominator. This modified index gives a more precise assessment of the lakes, because the abundance of Desmidiales, the only taxon originally used in the denominator, has dramatically declined during the past decades both in open water as in the littoral zone 34. PCQ, modified by Ott & Laugaste: PCQ = Cyanophyta* + Chlorococcales* + Centrales* + Euglenophyceae* + Cryptophyta* + 1 Desmidiales* + Chrysophyceae* + 1 Class boundaries used for assessment of ecological status of transboundary lakes see in Annex I 4. Description of the community (FPK): There are four possible categoryes: 1 – High/Good ‐ abundance (biovolume) of species is more or less equal it is impossible to determine dominants 2 – Moderate ‐ 2‐5 species dominate in abundance (biovolume) (>80%) 3 – Poor ‐ 1 species dominates in abundance (biovolume) (>80%) 4 – Bad ‐ Prevailing genera by abundance (biovolume) >50% are Microcystis, Aphanizomenon, Radiocystis, Planktothrix, Limnothrix, Woronichinia, Anabaena or alga from order Chlorococcales. The content of Chl a is > 20 mg/m3. Ecological status in lake water bodies was assessed using principle where each of parameter has equal weight. Each quality class has own score: high – 1; good – 2; moderate – 3; poor – 4; bad – 5. Arithmetical average gives hint to final score which is achieved by rounding off. Final scores according to quality classes: high: 1‐ 1,5; good: 1,51 ‐ 2,5; moderate: 2,51 ‐ 3,5; poor: 3,51 ‐ 4,5; bad: 4,51 – 5 . B.2.2. Benthic macroinvertebrates
In total, 14 lakes (9 in Estonia, 2 in Latvia, 3 transboundary lakes) were sampled for assessment of the benthic macroinvertebrates. In all 3 transboundary lakes joint samplings were carried out by Estonian and Latvian experts to compare and harmonise sampling in practice. The Estonian team performed sampling procedures according to the Swedish method35 described in the chapter B.1.2., while the Latvian team used multi‐habitat sampling approach. Sampling sites were selected in the most typical lake shore sections (approximately 10 m long). For the 10 sampling units were taken using kick sampling technique from the most typical substrate types (microhabitats) using 32
G. Nygaard, Hydrobiological Studies in some Danish ponds & lakes II. The quotient hypothesis and some new or little known phytoplanktons, K. Damske Viedersk Selsk Biol. Skrifter PP 1 – 293, 1949 33
Ott, I. & R. Laugaste, 1996. Fütoplanktoni koondindeks (FKI). Uldistus Eesti väikejärvede kohta. Eesti Keskkonnaministeeriumi Infoleht Nr. 3. 34
Kangro K.; Laugaste R., Noges P., Ott I. , 2005. Long‐term changes and seasonal development of phytoplankton in a strongly stratified, hypertrophic lake. Hydrobiologia, 547, 91 ‐ 103 35
Medin M., Ericsson U., Nilsson C., Sundberg I., Nilsson P.‐A., 2001. Bedömningsgrunder för botten fauna undersökningar. Medins Sjö‐ och Åbiologi AB. Mölnlycke, 12 pp. 34 standard hand net (frame size of 0.25 x 0.25 m; mesh size – 0.5 mm) at the shallow littoral zone (water depth < 0.6 m). Total taxon richness T (taxa identified according to Johnson´s list36, modified for local conditions), Shannon diversity H´, sensitive (Ephemeroptera, Plecoptera and Trichoptera), taxon richness EPT37, Average Score Per Taxon ASPT38, and Swedish Acidity Index SAI39 were used by Estonian experts. Latvian experts used the same indexes except SAI. The reference values in Estonia and class boundaries for all indices in all river types and subtypes are presented in following table (Table B.2.2.). Latvian experts used the same reference values and class boundaries. Table B.2.2. Reference values (R) and class boundaries for macroinvertebrate indices in lakes Index Lake type and habitat R High Good Moderate Poor or bad T hardwater, vegetation 35 >32 28‐32 21‐27 <21 T hardwater, sand or stones 27 >24 22‐24 16‐21 <16 T softwater, dark 16 >14 13‐14 10‐12 <10 T softwater, light 22 >20 18‐20 13‐17 <13 EPT hardwater, sand or stones 9 >8 7‐8 5‐6 <5 EPT hardwater, vegetation 6 >5 5 4 <4 EPT softwater, dark 4,5 >4 4 3 <3 EPT softwater, light 7 >6 6 4‐5 <4 T hardwater, vegetation 3,1 >2,8 2,4‐2,8 <2,4‐1,8 <1,8 T hardwater, sand 1,9 >1,7 1,5‐1,7 <1,5‐1,1 <1,1 T hardwater, stones 2,6 >2,4 2,1‐2,4 <2,1‐1,6 <1,6 T softwater, dark 2,3 >2 1,8‐2 <1,8‐1,4 <1,4 T softwater, light 2,7 >2,5 2,2‐2,5 <2,2‐1,6 <1,6 ASPT hardwater, sand or vegetation 5,7 >5,1 4,5‐5,1 <4,5‐3,4 <3,4 ASPT hardwater, stones 6,3 >5,7 5,1‐5,7 <5,1‐3,8 <3,8 ASPT softwater, dark 6,7 >6 5,3‐6 <5,3‐4 <4 ASPT softwater, light 6,3 >5,7 5,1‐5,7 <5,1‐3,8 <3,8 SAI hardwater, sand or vegetation 7 >6 6 4‐5 <4 SAI hardwater, stones 8 >7 6 5 <5 SAI softwater, dark 1 0‐1 2‐3 4‐5 >5 SAI softwater, light 5 5 4 or 6 3 or 7 <3 or >7 All values of high quality were assigned five points, values of good quality ‐ four points, values of moderate quality ‐ two points, and values of poor and bad quality ‐ zero points. The difference between good level and moderate level was intentionally emphasized in order to underline the principal difference between them in terms of the WFD. 36
Johnson R.K., 1999. Benthic macroinvertebrates. In: Bedömningsgrunder för miljökvalitet. Sjöar och vattendrag. Bakgrundsrapport 2. Biologiska parametrar (Ed. by Torgny Wiederholm). Naturvårdsverket Förlag, 85‐166. 37
Lenat D.R., 1988. Water quality assessment of streams using a qualitative collection method for benthic macroinvertebrates. ‐ Journal of North American Benthological Society 7: 222‐233. 38
Armitage P.D., Moss D., Wright J.F., Furse M.T., 1983. The performance of a new biological water quality score system based on a wide range of unpolluted running‐water sites. – Water Research 17: 333‐347. 39
Johnson R.K., 1999. Benthic macroinvertebrates. In: Bedömningsgrunder för miljökvalitet. Sjöar och vattendrag. Bakgrundsrapport 2. Biologiska parametrar (Ed. by Torgny Wiederholm). Naturvårdsverket Förlag, 85‐166. 35 Multimetric quality (MMQ) was then calculated by adding up the corresponding points. Hence, the reference value was 25 and the sum 23−25 was considered to indicate high, 18−22, good, 10−17, moderate, 6−9, poor and <6, bad status. Latvian team used only 4 indices and scaled down MMQ values. The reference value was 20 and the sum 18−20 was considered to indicate high, 14−17, good, 10−13, moderate, 6−9, poor and <5, bad status. B.2.3. Macrophytes
In total, 14 lakes (9 in Estonia, 2 in Latvia, 3 transboundary lakes) were investigated, and the status of lakes according to macrophytes was assessed. In 3 lakes the joint fieldworks were carried out (location of transboundary lakes see in Figure C.1.a.) Estonian and Latvian experts examined the lake vegetation from a boat along the shores. A sampling transect was established for approximately every 200‐ 300 meters. In each transect, which started from the water line and reached to the maximum depth of macrophyte occurrence, the taxonomic composition was registered, species abundances and their maximum colonization depth were measured. Separately also the abundance estimations of filamentous algae were given. For describing changes in aquatic macrophytes the species were classified into three different ecological groups – emergent, free‐floating and floatingleaved, and submerged plants40 41. Species abundances were given separately in these three groups and the assessment of the abundances was based on the Braun‐Blanquet scale42. This scale was modified by dividing it into five units, where 1 = very rare, 2 = rare, 3 = common, 4 = frequent and 5 = abundant. In ecological status assessment only submerged, floatingleaved, free‐floating species and filamentous algae were used as indicator species. Species were ordered by their abundances (marked with Arabic numerals) using following abbreviations:  Submerged species: Bry – Bryophyta; Char – Charophyta; Cer – Ceratophyllum spp.; Elo – Elodea spp.; Iso – Isoёtes lacustris L.; Lob – Lobelia dortmanna L.; Myr – Myriophyllum spp.; Pot – Potamogeton spp.; Ran – Ranunculus circinatus L.; Spar – Sparganium spp.; Sphag – Sphagnum spp.; Str – Stratiotes aloides L.; Utr – Utricularia spp.  Floating‐leaved species: Nu – Nuphar spp.; Nym – Nymphaea spp.; Pot (nat) – Potamogeton natans L.; Poly – Polygonum amphibium L.; Spar – Sparganium spp.  Free‐floating species: Hydr – Hydrocharis morsus‐ranae L.; Lem – Lemna spp.; Spir –Spirodela polyrhiza Schleid. The width of different macrophyte zones were measured using Estonian Land Board map server43. Lake overall status estimation (I – high; II – good; III – moderate; IV – poor; V – bad) was determined on the basis of different macrophyte indices which were characteristic to this lake type. Ecological status class boundaries according to lake types represented in joint sampling sites are described in table B.2.3. 40
Arber, A., 1920. Water plants. A study of aquatic angiosperms. Cambridge University Press, Cambridge: 436 pp. Sculthorpe, C. D., 1967. The biology of aquatic vascular plants. St. Martin’s Press, New York: 610 pp. 42
Braun‐Blanquet, J. (1964). Pflanzensoziologie: grundzüge der vegetationskunde Zweite, umgearbeitete und vermehrte Auflage. Springer‐Verlag: Wien. 865 pp. 43
Estonian Land Board Geoportal. http://xgis.maaamet.ee/xGIS/Xgis. (19.12.2012). 41
36 Table B.2.3. Macrophyte‐based ecological status classification for tranboundary lakes and ecological quality indicators Quality indicator Unit High status
Good status Moderate status
Poor status
Bad status Free floating plants =
floating‐leaved plants = Ceratophyllum Absent 0
0 Type II: shallow lakes with medium hardness of water (Lake Murati/Muratu) Phytocenosis (MTX)
Abundance of Potamogeton perfoliatus L. and/or Potamogeton lucens L. (PP) Abundance of charophytes and/or bryophytes (CHBR) Abundance of Ceratophyllum and/or free floating species (CELE) Abundance of large filamentous algae (FIAL) Description of more important hydrophytes by turns of abundance Braun‐Blanquet
scale (0–5) Bryophyta,
Charophyta, Potamogeton Charophyta = Potamogeton, Bryophyta = Elodea = Myriophyllum = Ceratophyllum ≥4
2‐3
Ceratophyllum =
Ranunculus = floating‐ leaved plants, Myriophyllum = free floating plants = Potamogeton = Charophyta 1
Braun‐Blanquet
scale (0–5) 3
4‐5
2
0
0 Braun‐Blanquet
scale (0–5) 0
1–2
3
4–5
– Braun‐Blanquet
scale (0–5) 0
1
1‐2
3–4
5 >4
4–>3
3–>1.6
1.6–1
<
1 Bryophyta =
Charophyta, Potamogeton Charophyta = Potamogeton, Bryophyta, Myriophyllum = Elodea Ranunculus, Ceratophyllum,
Potamogeton, Charophyta Ceratophyllum,
Ranunculus, free floating plants Absent 3
4‐5
1‐2
0
0 Type III: deep lakes with medium hardness of water (Lake Kikkajärv / Ilgajs) Maximum depth aquatic vegetation Phytocenosis (MTX)
of Abundance of
Potamogeton perfoliatus L. and/or Potamogeton lucens L. Meters
Description of more
important hydrophytes by turns of abundance Braun‐Blanquet
scale (0–5) 37 (PP) Abundance of charophytes and/or bryophytes (CHBR)
Abundance of Ceratophyllum and/or free floating species (CELE) Abundance of large filamentous algae (FIAL) 3
4‐5
1‐2
0
0 Braun‐Blanquet
scale (0–5) 0
1–2
3
4–5
– Braun‐Blanquet
scale (0–5) 0
1
1‐2
3–4
5 Braun‐Blanquet
scale (0–5) Type V: softwater light coloured lakes (Lake Väike Palkna /Mazais Baltins) Maximum depth of mosses (only in lakes with mean depth >3m) Phytocenosis (MTX)
Abundance of Isoëtes spp. or Lobelia dortmanna L. (ISLO) Only in Võru County:
abundance of Myriophyllum alterniflorum DC Abundance of Elodea or Potamogeton (submerged species) (ELPO) Abundance of large filamentous algae (FIAL) meters
>7
7–4
4–2
<2
<2 Description of more important hydrophytes by turns of abundance Lobelia dortmanna,
Isoëtes = Bryophyta, Myriophyllum alterniflorum Floating‐leaved species, Potamogeton, Elodea, Bryophyta, Isoëtes, Lobelia dortmanna Absent or floating‐
leaved species Absent Braun‐Blanquet
scale (0–5) 5
Isoëtes = Lobelia dortmanna = Myriophyllum alterniflorum, Bryophyta = Nitella = Chara delicatula 4–3
1‐2
0
– Braun‐Blanquet
scale (0–5) 3‐4
5
1‐2
0
‐ Braun‐Blanquet
scale (0–5) 0
1
2‐3
Absent
Absent Braun‐Blanquet
scale (0–5) 0
1‐2
3
4
─ 38 B.2.4. Fish
Fish were sampled in 10 lakes (7 in Estonia, 3 transboundary lakes) in July 2012 only by Estonian experts. Sampling was conducted using ’Nordic’‐type of multimesh gill nets (benthic nets according to European Standard EVS‐EN 14757:2005) and pelagial nets 1,5 m in depth. For background data especially for the data on piscivorous and larger individuals commercial monofilament nylon gill nets (30‐m in length and 1.5 m deep) with mesh sizes 30, 45 and 60 mm knot‐to‐knot were fished with. Both littoral and pelagial were sampled considering the oxygen conditions and depth strata. Two benthic and two pelagial ’Nordic’gillnets and three 30‐m long commercial gillnets fished overnight (12 hours, usually set between 6 and 8 p.m. and lifted between 6 and 8 a.m.). On lakes just before or after the setting of gillnets, three distinct types of mini‐fyke nets (Fig. B.2.4.) were set to fish. In several lakes e.g. Kiiviti, the selection of the sampling area was affected by low water level, profuse vegetation, trees dropped into water etc. Locations of the fishing gears see in the Estonian partners report. Figure B.2.4. Types of mini‐fyke nets used for sampling fish in littoral All nets and mesh sizes were analysed separately specifying each individual and measuring for total length (mm) and total weight (up to 0.1 g). Keyboarded data were transformed into a database used to proceed indices for each lake such as the number of species caught per lake, average numbers and total weight of individuals per ‘Nordic’ type of gill net (NPUE and WPUE), and variables used in LakeFish assessment methods (LaFiESTA, LAFIEE), modified German LakeFish assessment method and LakeFish Baltic/Central Geographical Intercalibration Group’s assessment method. Calcified structures (operculum for percids, cleithrum for pike, and scales for cyprinids) were removed and stored in fridge later on to clean and dry before using for aging to assess the length‐at‐age structure of fish populations. Piscivores were explored for gorged and/or digested food items according to Bagenal44. Estonia does not have an approved national method to assess neither water quality nor ecosystems’ integrity. Since 2007 we have used mainly the components of the Swedish index EQR845 in addition to the index of non‐piscivorous fish in a catch derived from the Finnish EQR4. Although the Central‐Baltic assessment system for lake fish (developed by D. Ritterbusch) recommends cyprinids especially roach and bream as sensitive species, for Estonian lakes the share of perch in a catch has given the values best correlated with the EU‐wide method developed in CEMAGREF (France). First in 2010 we tried to assess water quality/ecosystem integrity using LaFiEstA and derived from that LAFIEE. Consent with Dr. D. Ritterbusch we have a permission to use the template to calculate the values of B/C and modified German method. Our experience has shown that water quality/ecosystem integrity of lakes 44
Bagenal, T. B. 1978. Aspects of fish fecundity in ecology of freshwater fish production. Blackwell Scientific Publications: 75–102 45
Holmgren, K., A. Kinnerback, S. Pakkasmaa, B. Bergquist and U.Beier, 2007. Bedomningsgrunder for fiskfaunans status isjoar. Fiskeriverket Informerar 3: 54 39 with small area and those locating in bog might be the hardest to reflect. As fish both diminish nutrient load/food items and simultaneously emit metabolites they should not be considered the most exact reverberators of ambient conditions. On the other hand fish certainly find the best ambience available and thrive only on high nutrient load. Fishing data are used to calculate the following indices (metadata):  Numbers of individuals per Nordic gill net  Percentage of mesh sizes that captured fish  Share of non‐piscivorous fish in a catch (professional gill nets included)  Simpson Dw (Nordic gill nets only)  Simpson Dn (Nordic gill nets only)  Share of perch in Nordic gill nets (average of numbers and weight)  Numbers of cyprinid individuals per cyprinid species  WPUE ‐ average numbers of individuals per Nordic gill net  NPUE‐ total weight of individuals per Nordic gill net  Median weight of a captured fish, Nordic gill nets only  Index of piscivorous perch  Ratio of percid weight per cyprinid weight  Ratio WPUE of pelagial per benthic Nordic gill nets  Ratio NPUE of pelagial per benthic Nordic gill nets  Three the most frequent cyprinid species in a catch  Presence of species in a lake Nordic gill nets  Littoral species missing Using the proceeded metadata four different assessments are derived: LaFiEstA, LAFIEE, Central‐ Baltic and the modified German. Expert judgement was used for final assessment of ecological status according to fish because methods are on developmet stage still and class boundaries are defined only for LaFiEstA and LAFIEE (see Annex I). 40 B.3. Sampling, treatment and class boundaries for ecological status assessment in the coastal waters B.3.1. Sampling and treatment for ecological status assessment in the coastal
waters
B.3.1.1. Sampling and treatment for physico-chemical water quality elements
In the coastal area from Vitrupe to Ainaži, observations – CTD, water transparency and underwater video observations, water samples were taken in total 145, on 16 – 21 August 2012. Analyses of the samples were carried out by:  Laboratory of Marine Monitoring Department, Latvian Institute of Aquatic Ecology (LIAE) – Chlorophyll a and yellow substance in the surface water, turbidity of water; total C and N, aluminium, iron and manganese concentration in suspended matter. Department is accredited in Latvian National Accreditation Bureau (Standard LVS EN ISO/IEC 17025: 2005)  CTD, water transparency and underwater video observations and water sampling were done manually from the motorboat by the specialists of the Latvian Institute of Aquatic Ecology. Sampling was performed following HELCOM and Standard Activity Procedures, which are partly based on ISO/EN standards (Table B.2.3.1). Table B.3.1. List of methods and corresponding ISO/EN standards used within observation and sampling in the coastal area Parameter Standards followed CTD ISO 15839:2003 Water quality ‐‐ On‐line sensors/analysing equipment for water ‐‐ Specifications and performance tests. According to producer manual. Water transparency Semi‐quantitative method following ISO 7027:1999 Water quality – Determination of turbidity Water sampling LVS EN ISO 5667‐1:2007 Water quality ‐‐ Sampling ‐‐ Part 1: Guidance on the design of sampling programmes and sampling techniques LVS ISO 5667‐9:1992 Water quality ‐‐ Sampling ‐‐ Part 9: Guidance on sampling from marine waters Chlorophyll a HELCOM COMBINE Guidance (1997) Turbidity ISO 7027:1999 Water quality ‐ Determination of turbidity Bottles for water samples. Precleaned polyethylene bottles of 5 L with plastic screw‐cap and insertion were used for water samples for determination of Chlorophyll a, turbidity, yellow substance, concentration of suspended matter, total carbon and nitrogen, aluminium, iron and manganese. Temperature and conductivity versus depth profiles were carried out with a CTD probe. Salinity was computed. Water transparency was measured with Secchi disc (diameter 30 cm). Water sampling for measurements of chlorophyll a, turbidity and yellow substance in water column as well as total carbon and nitrogen, aluminium, iron and manganese in suspended matter was carried out with:  Van Dorn bathometer in a depth 1 – 4 m;  5 m long integrated plastic hose in a depth 5 – 9 m; 41 
10 m long integrated plastic hose in a depth >10 m. Water samples were immediately delivered for filtration. Samples before filtration were kept in fridge at the temperature of 4‐8 OC. Chlorophyll a filtration. Filtration for determination of the concentration of chlorophyll a was carried out immediately after sampling and GF/F grade (0.7 µm) fiber glass filters were used. Filtration was carried out on vacuum filtration stand and the suction pressure didn’t exceed 30 (mBar). Filtration time didn’t exceed 30 min. After drying, filters were kept in freezer at the temperature ‐4C until the initiation of analyses. Filtration for determination total C and N in suspended matter. Preheated (at 450 OC for 2 h) GF/F grade (0.7 µm) fiber glass filters were used for the water filtration. Filtration was carried out on the vacuum filtration stand (40 mBar) equipped with stainless steel filter holder. The filters with suspended particles after filtration were placed on the aluminium foil and kept in desiccator with silica gel until filters became dry. Dry filters were wrapped in foil and stored in the freezer ‐18 OC until the initiation of analyses. Filtration for determination Aluminium, Iron and Manganese in suspended matter. Preweighed Millipore™ nitrocellulose membrane filters (pore size 0.45 µm, Ø 47 mm) were used for the water filtration. Filtration was done on the vacuum filtration stand (40 mBar) equipped with polycarbonate filter holder. The filters with suspended particles after filtration were placed on ash‐less filtration paper in dust free plastic box until filters became dry (approx. 2 h). Dry filters were put in precleaned plastic hermetically sealed Petri dishes. Petri dishes with filters were kept in a plastic zip‐lock bag at room temperature until weighing for determination of the concentration of suspended matter in the coastal water and further analyses. Unfiltered water was used for turbidity determination. Filtrated water was used for determination of yellow substance. Digestion of filtrate material for determination of trace metals in suspended matter were done according to modified method by Hovind and Skeidescribed in ICES research report (1992) 46. The basis of method was total filter digestion with boiling acid mixture (HNO3 and HCl) in Teflon beakers. The measurements of trace metals in solution were performed by atomic absorption spectroscopy, for major elements Al, Fe and Mn by flame atomization, following US EPA methods 7000B (2007). Determination of yellow substance was performed by spectrometric method – filtered sample water measurements against distillate water at wave length 380 nm. B.3.1.2. Sampling and treatment for biological water quality elements
On 25 – 26 August 2012, during hard‐bottom macrobenthos sampling in the coastal area in total 27 samples were collected. Hard‐bottom macrobenthos sampling was accomplished by divers of the LIAE. Underwater video observation was done from the inflatable boat. Information was recorded by waterproof drop‐down camera 0.5‐1 m above the seabed. From each observation site a video material of 3 min (or 1 min in case of completely soft bottom) covering an area of at least 15 m2 was obtained. 46
ICES cooperative research report by Hovind, H. and Skei, J. 1992. Report of Second ICES intercomparison exercise on the determination of trace metals in suspended particulate matter. No 184. 42 In laboratory video was analysed by estimating the percentage cover of mussels, barnacles, dominant macroalgae (where 100 % correspond to the total cover of substrate) and the percentage cover of substrate fractions. Substrate was divided in three classes according to the diametrical size of fractions: sand and gravel (<60 mm), stones (60‐100 mm) and stones (>100 mm). Macrobenthos sampling. Macrobenthos samples (1‐3 replicates per station depending on phytobenthos richness) were collected by scuba divers. A metal frame of 0.02 × 0.02 m was put on a stone with a representative phytobenthos cover and all of the organisms within the frame were scratched in a collection bag (500 μm mesh size). The samples were preserved in a 4% formaldehyde solution. In addition, divers performed visual observations in each sampling station by taking a 10 m long and ~2 m wide diving transect of a random direction. In this transect the percentage cover of epilithic fauna (mussels, barnacles) and flora and the composition and cover of different substrate fractions was visually estimated. Identification of macrobenthic taxons was done using corresponding handbooks47. Before weighing organisms were dried at the temperature of 60°C during 3 days until a constant weight was obtained. Biomasses were determined in the accuracy of 0.0001 g. Abundance and biomass values were calculated per m2. B.3.2. Class boundaries for assessment of ecological status
Considering the similarities in Latvian and Estonian ecological status assessment systems (Chapter A.3.3.) and information and data analysis done in this project (Chapter C.4.), five parameters are recommended as ecological status indicators for the Gulf of Riga (Table B.3.2.a. and B.3.2.b.). Table B.3.2.a. Recommended physico‐chemical parameters and chlorophyll a parameter and their criteria values for the Gulf of Riga Parameter units season High
Good
Ecological status Moderate
Poor Bad
Transparency m summer >5.0 3.0‐5.0 <3.0‐2.0 <2.0‐1.5 <1.5 Total phosphorus μmol/l winter <0.6 0.6‐1.0 >1.0‐2.5 >2.5‐8.0 >8.0 μg/l summer <2,0 2,0‐6,5 >6,5‐16,0 >16,0‐40,0 >40,0 Concentration chlorophyll a of Table B.3.2.b. Recommended phytobenthic parameters and criteria values for the Eastern coast of the Gulf of Riga (waterbody F) Parameter Deviation from reference value Depth limit of Fucus vesiculosus Depth limit of macrovegetation Ecological status Moderate
Poor units ref. cond. High
Good
% <10 10‐25 >25‐45 >45‐70 >70 m 7 >6.3 6.3‐5.25 <5.25‐3.85 <3.85‐2.1 <2.1 m 11 >9.9 9.9‐8.25 <8.25‐6.05 <6.05‐3.3 <3.3 Bad
47
Pankow H., 1990. Ostsee – Algenflora and Tolstoy A., Osterlund K., 2003. Alger vid Sveriges östersjökust – en fotoflora. 43 Physico‐chemical and chlorophyll a parameters Unlike in Table A.3.3.b., where three physico‐chemical parameters are discussed, in Table B.3.2.a. only two of them have been left due to significant differences between Latvian and Estonian boundaries of ecological classes for parameter “total nitrogen”. This parameter could be developed as indicator only after harmonizing research between involved countries. Both systems for other two physico‐chemical parameters – total phosphorus and transparency – were analyzed, as they were similar, and boundaries for each class were more or less averaged. Phytobenthic parameters As historical data are available only for macroalgae depth limits and Estonian assessment system is based on this type of indicator, this project focused on ecological class boundary development for the depth limit of total macrovegetation and for the depth limit of macrophyte key‐species Fucus vesiculosus in the Eastern coast of the Gulf of Riga. Such depth limits have been shown to respond to changes in nutrient concentration and water clarity48 49 and the impact of water clarity on macroalgae has been ascertained in this Project as well. The macroalgae demand hard substrate for attachement, so the F. vesiculosus depth limit indicator is only applicable in areas where hard substrate occurs to the maximum water depth where light allows the growth. Latvian waterbody F mostly meet this requirement50. The reference value and boundaries of the ecological classes for both phytobenthic indicators are being suggested as shown in Table B.3.2.b. Reference value was based on investigations of H. Skuja 51 but slightly reduced due to higher wave exposure and an overall trend of more eutrophicated waters on the eastern coast of the Gulf of Riga than on the Western (due to the effect of prevailing winds and direction of the largest river runoffs). Determination of the class boundaries and the acceptable deviation was based on expert judgement and related literature52 53 54. According to OSPAR Common Procedure for Indentification of the Eutrophication Status of the Maritime Area the acceptable deviation from reference conditions can be restrictive (15%), intermediate (25%) or (non‐restrictive (50%) (Andersen et al. 2006). Based on current study the intermediate deviation was considered appropriate. Class boundaries for both indicators were developed for a single plant. 48
Nielsen S.L., Sand‐Jensen K., Borum J., Geertz‐Hanse O., 2002. Depth colonisation of eelgrass (Zostera marina) and macroalgae as determined by water transparency in Danish coastal waters. Estuaries, 25: 1025‐1032. 49
CHARM, 2003. Small‐scale vegetation models. Project deliverable No. 15, 36 pp. 50
Stiebrins O., Väling P., 1996. Bottom sediments of the Gulf of Riga. 1:200 000, Riga, 54 pp. 51
Skuja H., 1924. Mērsraga – Ragaciema piekrastes aļģes. Acta Univ. Latviensis, 10: 337–392 (in latvian and german). 52
Andersen J.H., Conley D.J., Hedal S., 2004. Palaeoecology, reference conditions and classification of ecological status: the EU Water Framework Directive in practice. Marine Pollution Bulletin, 49: 283‐290. 53
Krause‐Jensen D., Greve T.M., Nielsen K., 2005. Eelgrass as a Bioindicator Under the European Water Framework Directive. Water Resources Management, 19: 63‐75. 54
Andersen, J. H., Schlüter, L., Ærtenjerg, G. 2006. Coastal eutrophication: recent developments in definitions
and implications for monitoring strategies. Journal of Plankton Research, 28(7), 621-628. 44 B.4. Sampling and treatment methods for assessment of hazardous substances in transboundary waters B.4.1. Selection of matrixes, hazardous substances and sampling sites
In the frame of the Gauja/Koiva project the analysis of the hazardous substances were performed in the following matrixes:  surface waters of the water bodies,  sediments of the water bodies,  biota (fishes or mussels) of the water bodies. The major criteria for the selection of hazardous substances to be analysed in the frame of the project were the following:  the priority was given for the substances or groups of substances’ identified among those where the limits on concentrations in surface waters are set (or will be set) on European level (i.e. 33 priority substances and 12 other pollutants in candidate list) according to previous EQS Directive 2008/105/EC;  the biggest gaps of information of occurrence of priority substances in the aquatic environment;  the facts that certain substance or group of substances occur on the market and/or were used in past, these substances are persistent, bioaccumulative and toxic (PBT) ;  the facts on occurrence of substances in the environment from previous project experience (e.g. Brominated retardants);  the information about enzymatic reaction/activity of biota (bivalves) to pollution in the environment from previous project experience and publications. In total 10 substances and/or groups of substances were screened for water, sediments and biota. In surface water: Di(2‐ethylhexyl)phthalate (DEPH). In sediments: 1) metals: Cd, Cu, Zn, Pb, Ni and Hg; 2) alkylphenols and Bisphenol A; 3) Polybrominated diphenylethers (PBDE) and Hexabromocyclododecane (HBCDD); 4) Polyaromatic hydrocarbons (PAH); 5) Organic tin compounds; In biota samples (fish): 1) hexachlorobenzene; 2) hexachlorobutadiene; 3) brominated diphenylethers (PBDE) and Hexabromocyclododecane (HBCDD); 4) dioxins and furans; 5) polychlorinated biphenyls (PCB); In total 14 sampling sites for determination of hazardous substances were selected but in total 3 sites in the rivers and lakes on Latvia‐Estonia border were selected for screening transboundary impact. 45 Table B.4.1. Sampling sites and analysed matrixes taken in sampling round (Matrixes: SW ‐ surface water, BS ‐ bottom sediments, F – fish tissues, M – mussels) Matrixes Site Sampling site Sampling site description No. SW BS Biota
1. Gauja river On Latvia‐Estonia border, affected by agriculture 1 1 F/M
2. Pedele river On Latvia‐Estonia border in Valka town 1 1 ‐ 3. Lake Murati/Muratu On Latvia‐Estonia border 1 1 F/M
B.4.2.Sampling and handling


On 3 – 18 July 2012 sampling was organised to collect 3 surface water and 3 sediment samples at the sites indicated in the Table B.4.1.; In August – September 2012 fish (persch) from 2 sites were collected. B.4.2.1.Water, sediment and fish sampling procedures
Water and sediment sampling was carried out by the specialists of the Latvian Institute of Aquatic Ecology. Fish samples were sampled by a specialist of the Institute of Food Safety, Animal Health and Environment ‐ "BIOR". Sampling was performed according to the Standard Activity Procedures, which are based on ISO/EN standards. Bottles and jares for samples analysed at BIOR laboratory. Precleaned amber glass bottles of 1 L with plastic screw‐cap and aluminium foil insertion were used for water samples for analysis of phthalates. Precleaned glass jars of 1 L with plastic screw‐cap and polypropylene insertion were used for bottom sediment samples. Boxes for sediment at the laboratory of Latvian Institute of Aquatic Ecology (LIAE). Precleaned plastic boxes of 200 mL for sediment samples for analysis of heavy metals were used. For determination of phthalates in the surface water, the samples were taken manually from the inflatable boat or with telescopic rod equipped with sampling bottle holder from the riverside. Bottles were immersed with upside down and turned under water avoiding water surface film at a depth of approximately 0.3 ‐ 0.5 metres. The glows were used. Bottles were washed twice with sample water before filling with sample water. For determination of hazardous substances, LOI and grain size, total and organic carbon in the bottom sediments, the samples were taken manually with Wildco Ponar or VanVeen bottom grab sampler from the inflatable boat or with telescopic rod equipped with sampling beaker holder (beaker made from stainless steel) from the riverside. Sampling was performed at 5 ‐ 7 points around the observation site. All subsamples were placed in one precleaned box, mixed and sieved through sieve with mesh size of 2.0 mm to avoid large particles such as boulder, bivalves etc. Sieved sediment samples were immediately transferred to precleaned glass jars and plastic boxes. For determination of hazardous substances in the perches (Perca fluviatilis), the individuals were caught on a hook. 46 Transportation and storage of samples. Samples from sampling spot to the laboratory of LIAE were transported in the mobile cool boxes filled with frozen cooling agent cartridges right after sampling. Samples were kept in the fridge at the temperature of 4‐8 OC until transportation to BIOR laboratory in the mobile cool boxes filled with frozen cooling agent cartridges. Samples were kept in the fridge at the temperature of 4‐8 OC until analyses. Sediment samples for metal analyses were frozen at laboratory of LIAE until samples were freeze dried for further manipulations. Fish samples from fishing spot were kept and transported to the BIOR laboratory in the mobile cool boxes filled with frozen cooling agent cartridges right after catch. Samples were kept in the fridge at the temperature of 4‐8 OC overnight before transportation to BIOR laboratory. At BIOR laboratory the fishes were immediately dissected. Dissected soft tissues were kept in the freezer at the temperature ‐
18 OC until analyses. B.4.3. Analysis of the samples
Analyses of the samples were carried out by:  Laboratory of Marine Monitoring Department of Latvian Institute of Aquatic Ecology (LIAE) – trace metals, LOI, total C and N in bottom sediments and grain size of sediments; mercury in perch (Perca fluviatilis) and trace metals in bivalves (Macoma Balthica, Unionidae). Department is accredited in Latvian National Accreditation Bureau (Standard LVS EN ISO/IEC 17025: 2005). Certificate of Accreditation No. LATAK–T–169‐07‐99‐A from 17.12.2008, valid until 20.11.2012. and LATAK–T–169‐10‐99 from 21.11.2012., valid until 20.11.2017. All analyses were done accordind to ISO and/or US EPA standards.  Laboratory of Institute of Food Safety, Animal Health and Environment ‐ "BIOR", Latvia : phthalates in surface water; brominated diphenylethers and hexabromocyclododecane, polycyclic aromatic hydrocarbons (PAH) in sediments; brominated diphenylethers and hexabromocyclododecane, dioxins/furanes and dioxin like polychlorinated biphenyls (PCB), hexachlorobenzene and hexachlorobutadiene in perch (Perca fluviatilis). Laboratory is accredited in Latvian National Accreditation Bureau (Standard LVS EN ISO/IEC 17025: 2005) Certificate of Accreditation No. LATAK–T–012‐26‐95 from 24.07.2012, valid until 17.12.2014. All analyses were done accordind to ISO and/or US EPA standards, except PAO (Internal standard method based on several publications).  Eurofins Gfa Lab Service Gmbh, Germany, Hamburg – the subcontractor of BIOR Laboratory, Latvia – Organotin compounds, alkylphenols and bisphenol A in the bottom sediments. Laboratory is accredited in the Deutsche Akkreditierungsstelle GmbH (DAkkS) – national accreditation body for the Federal Republic of Germany. (Standard DIN ISO/IEC 17025:2005). Certificate of Accreditation No. D‐PL‐14629‐01‐00 from 02.08.2011., valid un till 04.03.2013. All analyses were done based on internal accredited methods. 47 C. Results of the investigations in transboundary waters of the Gauja/Koiva river basin district C.1. Locations for joint ecological status investigations of transboundary waters For joint investigations of transboundary waters were selected three tranboundary rivers: Vaidava/Vaidva, Peetri/Melnupe and Pedeli/ Pedele and three lakes located on the border between Estonia and Latvia: Lake Väike Palkna/Mazais Baltiņš, Lake Kikkajärv/Ilgājs/, Lake Murati/Muratu. In each selected river 2 sites were jointly sampled, one in Latvian side, another in Estonian side. In total 6 joint sampling sites were selected in rivers and 3 in lakes. Additionally three tranboundary rivers (Ujuste/Kaičupe, Pärlijogi/Pērļupīte, Pedetsi/Pedeze) were investigated separately by Latvian and Estonian experts in own country (Fig.C.1.a.). An exemption is the river Pedetsi/Pedeze where joint samplings were carried out also for joint investigations of benthic macroinvertebrates. Figure C.1.a. Joint sampling sites in transboundary waters For joint investigations of transboundary waters sampling was carried out for 4 biological quality elements: phytobenthos (only in rivers, Fig. C.1.b.), phytoplankton (only in lakes), benthic macroinvertebrates and aquatic macrophytes. Fish were not sampled jointly because of legal obstacles, but experts exchanged experience participating as observers during sampling in neighbouring countries (Figure C.1.c.). Figure C.1.b. Joint phytobenthos sampling (Photo: P.Pall) Figure C.1.c. Joint fish sampling (Photo: P.Pall) 48 C.2. Ecological status in the transboundary river water bodies C.2.1. Ecological status according to biological quality elements
C.2.1.1. Ecological status according to the benthic diatoms (Phytobenthos)
Joint sampling was conducted in three transboundary rivers: Vaidava/Vaidva, Melnupe/Peetri and Pedele/Pedeli. Two sites were sampled in each river, one sampling site per river was chosen in each country, 6 samples in total. Two transboundary rivers (Pärlijõgi/Pērļupīte, Ujuste/Kaičupe) were sampled and investigated in both sites of borders only by country experts (sampling sites see in Figure C.1.a.). The results were expressed by the means of three diatom indices: TDI, IPS and WAT and class boundaries were used the same in both countries (see chapter B.1.1. and Annex I). Comparison of calculated indices by Estonian and Latvian experts is shown in Table C.2.1. Values are marked in colours according to quality class boundaries of EU WFD using Estonian assessment method (blue – high, green – good, yellow – moderate, orange – poor, red ‐ bad). Table C.2.1.1. Values of diatom indices and ecological status according to diatoms assessed by Estonian (EE) and Latvian (LV) experts in transboundary rivers IPS value
River Vaidava Vaidava Melnupe/ Peetri Melnupe/ Peetri Pedeli/Pedele Pedeli/Pedele Pedetsi/Pededze Pedetsi/Pededze Pärlijõgi/Pērļupīte Pärlijõgi/Pērļupīte Ujuste/Kaičupe Ujuste/ Kaičupe WAT value
TDI value
Location in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia EE 13,6 13,6 12,8 14,5 13,8 14,2 ‐ 16.0 ‐ 16.2 ‐ 16.0 LV
14,3
14,6
14,5
15,2
13,5
12,9
14,5
‐
15,4
‐
14,3
‐
EE
14,1
14,1
12,5
15,0
11,0
14,7
‐
19.4
‐
17.8
‐
18.0
LV
15,5
14,9
12,5
13,9
12,0
16,9
15,0
‐
15,9
‐
15,2
‐
EE
53,4
53,4
89,1
72,6
67,9
64,5
‐
60.5
‐
58.1
‐
60.5
LV
54,2
70,0
81,0
71,9
63,4
66,1
69,7
‐
66,1
‐
77,0
‐
Ecological status according to diatoms EE LV Good Good
Good Good
Moderate Moderate
Good Good
Moderate Moderate
Good Good
‐ Good
High ‐ ‐ Good
High ‐ ‐ Moderate
High ‐ Thus results obtained from joint sampling showed small differences. During the meetings of experts, diatom species composition from each site was discussed and compared. Results are comparable. C.2.1.2. Ecological status according to the benthic macroinvertebrates
Joint sampling was conducted in four tranboudary rivers: Vaidava/Vaidva, Melnupe/Peetri, Pedele/Pedeli and Pedetsi/Pededze. Two sites were sampled in each river, one sampling site per river was chosen in each country, 8 samples in total. Two transboudary rivers (Pärlijõgi/Pērļupīte, Ujuste/Kaičupe) were sampled and investigated in both sites of borders only by country experts (sampling sites see in Figure C.1.a.). Experts sampled using slightly different methods (see chapter B.1.2.). 49 The results were expressed by the means of five indices: taxa richness, ASPT, EPT, DSFI, Shanon diversity, and class boundaries where used the same (see chapter B.1.2. and Annex I). Comparison of calculated indices by Estonian and Latvian experts is shown in Table C.2.1.2. Calculated metrics for investigated river sites mostly refer to good or/and high quality, except Pedele river at Latvian site, (estimated as moderate), Shannon’s diversity index values for 4 sites and some exceptions. Data by Latvian team showed higher variation but in general, the differences between results were not significant (mean EQR for Latvian rivers (n=8) was 0.92 but for Estonian rivers– 0.96 (n=8)) and could be explained principally by natural variation, sampling strategy and the taxonomical level of macroinvertebrate identification (e.g. Latvian team identified Oligochaeta to the species level, but Estonian team identified only to class level). Differences in the results of the assessment of ecological status of Kaičupe river could be related to the sampling at different river reaches (Latvian team sampled at river mouth, were river bottom is covered mainly with sand). Table C.2.1.2. Values of benthic macroinvertebrate indices and ecological status assessed by Estonian (EE) and Latvian (LV) experts in transboundary rivers River Location
EE LV EE LV EE LV EE LV EE LV Ecological status according to macroinvertebrates EE LV Taxa richness ASPT EPT DSFI Shannon diversity Vaidava in Latvia 53 68 6.79 6.6 26 31 7 7 3.8 2.0 High High Vaidava in Estonia
47 45 7.07 6.8 24 23 7 6 3.7 2.7 High High Melnupe/ Peetri in Latvia 51 77 6.23 6.6 21 29 6 7 3.7 3.4 High High Melnupe/ Peetri in Estonia
49 79 6.45 6.4 23 18 7 7 4.4 2.3 High High Pedeli/Pedele in Latvia 41 21 6.00 5.1 19 8 5 4 3.27 2.2 High Moderate Pedeli/Pedele in Estonia
35 49 6.08 6.1 13 16 6 4 1.5 3.1 Good High Pedetsi/Pededze in Latvia 40 30 6.00 6.1 18 14 6 6 2.6 2.3 High High Pedetsi/Pededze in Estonia
32 59 6.5 6.3 20 22 7 7 2.6 2.2 High High Pärlijõgi/Pērļupīte in Latvia ‐ 57 ‐ 6.09 ‐ 20 ‐ 6 ‐ 2.7 ‐ High Pärlijõgi/Pērļupīte in Estonia
44 ‐ 6.66 ‐ 23 ‐ 7 ‐ 3.81 ‐ High ‐ Ujuste/Kaičupe in Latvia ‐ 25 ‐ 3.57 ‐ 7 ‐ 4 ‐ 2.1 ‐ Moderate Ujuste/ Kaičupe in Estonia
33 ‐ 5.58 ‐ 15 ‐ 6 ‐ 3.11 ‐ High ‐ According to the joint sampling results it could be concluded, that the results of the assessment of ecological status are not significantly dependant on the sampling method (if different standard method are used) and the results are comparable. C.2.1.3. Ecological status according to the aquatic macrophytes
Joint observations were conducted in three tranboudary rivers: Vaidava/Vaidva, Melnupe/Peetri and Pedele/Pedeli. Two sites were observed in each river, one site per river was chosen in each country, 6 samples in total. Two transboudary rivers (Pärlijõgi/Pērļupīte, Ujuste/Kaičupe) were observed in both sites of borders only by country experts (sampling sites see in Figure C.1.a.). The results were expressed by MIR index and Estonian class boundaries were used in both countries (see chapter B.1.3. and Annex I). Comparison of results by Estonian and Latvian experts is shown in Table C.2.1.3. 50 Table C.2.1.3. Values of MIR index and ecological status of aquatic macrophytes assessed by Estonian (EE) and Latvian (LV) experts in transboundary rivers River Location Vaidava Vaidava Melnupe/Peetri Melnupe/Peetri Pedeli/Pedele Pedeli/Pedele Pedetsi/Pededze Pedetsi/Pededze Pärlijõgi/Pērļupīte Pärlijõgi/Pērļupīte Ujuste/Kaičupe Ujuste/ Kaičupe in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia Ecological status according to macrophytes EE LV High High High High Good High High High High High Good Good ‐ High* High ‐ ‐ High High ‐ ‐ Moderate Good ‐ Value of MIR index EE 46.2 42.4 37.6 39.7 47.3 36.4 ‐ 40.8 ‐ 44 ‐ 37.1 LV 47 46 42 42 45 34 43 ‐ 49 ‐ 34 ‐ *according to expert judgement river is at good ecological status Assessment results on ecological status according to according macrophytes shows small differences but are not significant. The assessment method should be more adapted to the Latvian conditions in future due to the differences between results developed using the MIR index and expert judgement. C.2.1.4. Ecological status according to the fish fauna
Estonian and Latvian experts sampled only in own countries using different sampling and assessment methods (see chapter B.1.4.). Results of ecological status according to the fish fauna in transboundary rivers are compared in Table C.2.1.4. Since different river sections were under observation, the comparison of results is not very correct. Also a bit different methods (indexes) were used: Latvian side used German method (index), Estonian side used Estonian method (index). On the other hand, when comparing the rivers, the results (quality classes) coincide well. Table C.2.1.4. Ecological status according to the fish investigations in the transboundary rivers River Location S FIBS Vaidava Vaidava Melnupe/Peetri Melnupe/Peetri Pedeli/Pedele Pedeli/Pedele Pedetsi/Pededze Pedetsi/Pededze Pärlijõgi/Pērļupīte Pärlijõgi/Pērļupīte Ujuste/Kaičupe Ujuste/Kaičupe in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia in Latvia in Estonia ‐
0.54
‐
0.62
‐
0.39
‐
0.56
‐
0.21
‐
‐
2.67
‐
2.58
‐
1.85
‐
2.63
‐
1,64 ‐
2,84
‐
Ecological status according to fish Good Good Good Good Poor Moderate Good Good Poor* Poor Good ‐ *sampling site is wrongly chosen (too close to a lake) and in a result sampled species aren’t typical for rivers 51 C.2.2. Physico-chemical water quality in transboundary rivers
Since overall physico – chemical water quality is assessed differently by Estonian and Latvian experts (see chapter B.1.5.) the results are not comparable. According to the Latvian approach the results of ecological status assessment derived by the expert judgement and the principle “one out – all out” are the same in all transboundary rivers. Table C.2.2.a. Values of physico‐chemical quality elements and assessment results of the ecological status by Latvian experts in transboundary rivers River Location Vaidava in Latvia Vaidava in Estonia Melnupe/Peetri in Latvia Melnupe/Peetri in Estonia Pedeli/Pedele in Latvia Pedeli/Pedele in Estonia Pedetsi/Pededze in Latvia Pärlijõgi/Pērļupīte in Latvia Ujuste/Kaičupe in Latvia *atypical for overall Temp, °C 17,8 15,2 18,5 18,0 17,1 17,5 14,3 13,9 14,9 pH 8,21 8,02 8,13 8,10 7,71 7,88 7,99 8,00 8,64 O2, mg/l
10,10
9,50
10,00
9,34
7,40
7,77
8,30
9,33
8,79
O2, % 81,0
96,5
109,7
101,1
78,4
83
83,8
93,2
88,9
N‐NO2, N‐NH4 mg/l mg/l 0.007 0.2071
0.009 0.231
0,01 0,362
0,01 0,358
0,014 0,390
0,03 0,302
0,01 0,377
0,01 0,119
0,004 0,080
Ntot, mgN/l
0,699
0,622
1,41
5,91*
1,45
1,39
0,89
0,777
0,46
BSP, One out all Expert Ptot mgP/l mg/l out judgement
0,031
Good Good
2.4 0,031 2.56 Good Good
0,046 2,08 Good Good
0,052 2,56 Modearte Moderate
0,081 4,64 Good Good
0,079 2,24 Good Good
0,03
2,88 Good Good
0,025
1,6 Good Good
n
11,84* Modearte Moderate
Water quality in monthly sampled sites indicates high ecological status (Table C.2.2.b.) Table C.2.2.b. Average values of physico‐chemical quality elements and assessment results of the ecological status by Estonian experts in monthly sampled sites Ntot, Ptot, Ecological BOD5, NH4, River Location Type O2 % pH mgO/l mgN/l mgN/l mgP/l status Pedetsi/Pededze Kiviora IIA 89 8.0 2.0 0.106 1.3 0.040 High Pedetsi/Pededze Missoküla IA 50 7.4 1.8 0.062 1.4 0.033 High Murati lake Vaidava IA 50 7.3 1.7 0.078 1.1 0.031 High outlet Vaidava Kuutsi IIB 80 7.7 1.8 0.028 1.2 0.049 High Vaidava Vastse‐Roosa IIA 84 7.7 1.4 0.054 1.3 0.044 High Peetri/Melnupe Leppura IIA 50 7.6 1.7 0.088 1.4 0.056 High Pärlijõgi/Pēļupīte in Estonia IIA 95 7.8 1.7 0.042 1.3 0.032 High Pedeli/Pedele Valga IIA 83 7.7 1.9 0.119 1.0 0.079 High Pedeli/Pedele Koorküla IA 75 7.5 2.0 0.039 1.1 0.080 High Small tranboundary rivers, type IA, water quality is high in all stations according to organic matter, ammonia, total nitrogen, pH indicator. Total phosphorus content is in the good class in one of the stations, other are in high class. By the oxygen content 2 rivers showed good status and one high status (Figure C.2.2.a). 52 1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
2.5
2.0
1.5
1.0
0.5
0.0
Pedetsi (Missoküla) Vaidava (Murati) Pedeli (Koorküla)
BOD5
Limit value - I class
Pedetsi (Missoküla) Vaidava (Murati) Pedeli (Koorküla)
Ntot
Limit value - I class
0.12
0.10
0.10
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0.00
0.00
Pedetsi (Missoküla)
NH4
Kuura
Pedetsi (Missoküla)
Vaidava (Murati)
Ptot
Limit value - I class
80
70
60
50
40
30
20
10
0
Kuura
Limit value - I class
Vaidava (Murati)
Limit value - II class
10
8
6
4
2
Pedetsi (Missoküla)
O2 %
Kuura
Limit value - I class
0
Vaidava (Murati)
Pedetsi (Missoküla)
Limit value - II class
pH
Kuura
Limit value - I class
Vaidava (Murati)
Limit value - II class
Figure C.2.2.a. Water quality of rivers of type IA Medium transboundary rivers (7 stations), type IIA, water quality is mostly high by all parameters. Only 2 stations showed good status, one of them by organic matter and other by ammonia content (Figure C.2.2.b). 4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
Pedetsi
(Kiviora)
Vaidava
Peetri
(Vastse-Roosa) (Leppura)
BOD5
Limit value - II class
Pärlijõgi
Pedeli (Valga)
Limit value - I class
Limit value - I class, type B
Pedetsi
(Kiviora)
Vaidava
(Kuutsi) - type
B
Peetri
(Leppura)
Ntot
0.35
Pärlijõgi
Pedeli (Valga)
Vaidava
(Kuutsi) - type
B
Limit value - I class
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
0.30
0.25
0.20
0.15
0.10
0.05
0.00
Pedetsi
(Kiviora)
Vaidava
Peetri
(Vastse-Roosa) (Leppura)
NH4
Limit value - I class
Pärlijõgi
Pedeli (Valga)
Pedetsi
(Kiviora)
Vaidava
(Kuutsi) - type
B
Pedetsi
(Kiviora)
Vaidava
Peetri
(Vastse-Roosa) (Leppura)
Pärlijõgi
Pedeli (Valga)
O2 %
Limit value - I class
Limit value - II class
Limit value - I class, type B
Vaidava
Peetri
(Vastse-Roosa) (Leppura)
Ptot
Limit value - II class
100
90
80
70
60
50
40
30
20
10
0
Limit value - I class
Pärlijõgi
Pedeli (Valga)
Vaidava
(Kuutsi) - type
B
Limit value - II class
10
9
8
7
6
5
4
3
2
1
0
Vaidava
(Kuutsi) - type
B
Pedetsi
(Kiviora)
Vaidava
(Vastse-Roosa)
pH
Figure C.2.2.b. Water quality of rivers of type IIA an IIB 53 Vaidava
(Vastse-Roosa)
Peetri
(Leppura)
Limit value - I class
Pärlijõgi
Pedeli (Valga)
Limit value - II class
Vaidava
(Kuutsi) - type
B
C.3. Ecological status in transboundary lakes C.3.1. Water quality according to biological quality elements C.3.1.1. Ecological status according to the phytoplankton
The results were expressed by the means of phytoplankton parameters: Clorophyll a, FKI, PCO, FPK, and Eveness (J) and class boundaries where used the same (see chapter B.1.1. and Annex I). Comparison of the calculated indices by Estonian and Latvian experts is shown in Table C.3.1.1. Values are marked in colours according to quality classes described in EU WFD. Table C.3.1.1. Values of indices and ecological status according to phytoplankton (in water column) assessment results by Estonian (EE) and Latvian (LV) experts Väike Palkna/ Kikkajärv/Ilgājs Murati/Muratu Mazais Baltiņš Parameters EE LV EE LV EE LV Chla, μg /l 18.2 4.9 33.2 9.33 3.8 0.65 3.2 3.8
3.2 PCQ/ FKI 3.63 6.24 2.11 FPK 2.22 2.0 3.25 2.4 2.55 1.75 Evenness (J) 0.61 0.56 0.44 0.53 0.51 0.67 Biomass (g/m3) ‐ 2.51 ‐ 10.6 ‐ 0.49 Ecological status Good Good Moderate
Poor Good High C.3.1.2. Ecological status according to the benthic macroinvertebrates
Results of the joint lake study by Latvian and Estonian teams were very similar and metrics differed insignificantly (Table C.3.1.2.). Differences could be mostly explained by the natural habitat heterogeneity at littoral zone and the taxonomic level of species identification. Results obtained using both sampling methods are comparable. Table C.3.1.2. Values of benthic macroinvertebrate metrics and ecological status assessment results by Estonian (EE) and Latvian (LV) experts Väike Palkna/ Kikkajärv/Ilgājs Murati/Muratu Mazais Baltiņš Parameters Estonia Latvia Estonia Latvia Estonia Latvia Taxon richness 25 51 35 40 26 52 ASPT 5.06 5.1 4.67 5 5.1 5 EPT 8 11 6 9 9 17 Shannon diversity 2.86 2.7 1.96 1.9 2.46 2.6 SAI 5 ‐ 6 6 ‐ MMQ 20 19* 20 17* 22 18* Ecological status Good High Good Good Good High * Latvian team calculated 4 indices and respectively scaled down MMQ values 54 C.3.1.3. Ecological status according to the aquatic macrophytes
In total 51 taxa were found in lakes, species richness ranged from 1 to 22 species per site 9 to 31 per lake. The number of investigated lakes is too small to say what species are charasteristic; lakes also are quite different for comparison. Table 3.1.3. Water quality according to macrophytes Väike Palkna/ Kikkajärv/Ilgājs Murati/Muratu Mazais Baltiņš Parameters EE LV EE LV EE LV DLS 4 ‐ ‐ ‐ ‐ ‐ MTX Cer=Pot=Nu, Pot, Nu Myr, Char Myr, Char Char, Myr Pot, Nup Poly=Ran PP 3 4‐5 4 2‐3 ‐ ‐ CHBR 1 4‐5 1 1‐2 ‐ ‐ CELE 3 1‐2 2 1‐2 ‐ ‐ ISLO ‐ ‐ ‐ ‐ 0 0 ELPO ‐ ‐ ‐ ‐ 1 High/Good FIAL 1 1‐2 2 1‐2 2 Good Ecological Good / Good Good Good Good Good Moderate status C.3.1.4. Ecological status according to the fish fauna
Fish samplings in lakes were carried out only by Estonian experts. Ecological status according to the fish fauna was assessed by the following indexes and parameters: B/C, DELaFi, Connectivity to other water bodies, LaFiEstA and LAFIEE (described in chapter B.2.4.). The results are showed in Table C.3.1.4. Table C.3.1.4. Ecological status according to fish indexes Indexes/ Kikkajärv/ Murati/ Väike Palkna/ paremeters Ilgājs Muratu Mazais Baltiņš B/C M B M DELaFi M M G Connectivity to other water bodies B B B LaFiEstA H H H LAFIEE B G B Ecological status Moderate Good Good Assessment of the ecological status is based on expert judgement taking into accont all indexes. LaFiEstA index indicates high ecological status, while other indexes indicate lower ecological status in lakes. The lack of rheophilic species in catch in all lakes appoint to a bad connection with rivers and large water bodies. 55 C.3.2. Physico-chemical water quality in transboundary lakes
In Latvia the water samples were taken at the same time when sampling for biological quality elements was carried out. In Estonia plankton and abiotic water samples are gathered at the same time (ussially 304 times per year) while other biological elements are investigated separately once per growing season. Physico–chemical quality elements were analysed according to requirements of national legislations. The overall assessment of the ecological status for lakes was based on expert judgement in both countries. According to the water chemical properties the lake Väike Palkna/ Mazais Baltiņš belong to the type 10 lake as it is deep softwater clear water lake (conductivity < 165 mkS/cm, water colour < 80 Pt‐Co). Deep lakes are stratified and there are differences in temperature and oxygen concentration and saturation. Such type of lakes is not designated as separate water bodies in the Gauja RBD due to the fact that the lake Mazais Baltiņš or other similar lakes have the surface size below the threshold (50ha) to be identified as a speperate water body. Table 3.2. Water quality according to physico‐chemical water quality elements by Estonian (EE) and Latvian (LV) experts* Väike Palkna/ Kikkajärv/Ilgājs Murati/Muratu Mazais Baltiņš Parameters Estonia Latvia Estonia Latvia Estonia Latvia** pH 8,1 ‐ 7.88 ‐ 7.16 ‐ Total‐P (µg/l) 1300 12 – 34 32‐38 80 20‐30 26 Total‐N (µg/l) 3842 1270 1050 1160 ‐ 2510
620 376‐575 Secchi(m) 3,1 2.1‐2.9 0.9 0.8‐0.9***
3.4 2.6‐3.9 Range of 4 ‐ ‐ ‐ ‐ ‐ metalimnion (m) Ecological status Moderate Moderate
Good Moderate Moderate Good * Latvian experts assessed the physico‐chemical status according data at 0.5 m depth, Estonians analysed water column **The class boundaries for assessment of this type of lakes in Latvia has not been developed (as there was opinion that such type of lakes doesn’t exist in Latvia); the quality was assessed according demands to 9 type *** Secchi depth isn’t used for polyhumic lake Lake stratification is not taken into in the physico‐chemical water quality assessment of the lake water quality in Latvia. Therefore sampling results from 0.5m depth and additionally the experts’ judgment for general assessment was implemented. This is not in line with the official principle „one out‐ all out” approach. 56 C.4. Water quality in coastal waters Three biological parameters and two physico‐chemical parameters were recommended as the most suitable indicators for the coastal waters of the Gulf of Riga (Table C.4.) and water quality was assessed according to their criteria values. For quality assessment the project area was divided in three polygons – below, above and in the vicinity of the Salaca River mouth (Figure C.4.). Figure C.4. Project area divided in three polygons where ecological status was evaluated In general, all five parameters indicate moderate ecological status in all three polygons (Table C.4.). Slight differences are shown by the concentration of chlorophyll a that indicates good status below the Salaca River mouth (polygon 3), most likely due to the coastal upwelling during the sampling period. In the vicinity of the Salaca River mouth (polygon 2) depth limit of Fucus vesiculosus as well as water transparency show ambiguous situation – whereas moderate status dominates, some transects show poor status. Above the Salaca River mouth (polygon 1) water transparency also indicates between moderate and poor ecological status. In conclusion, the ecological status of the coastal waters of the Gulf of Riga near Salaca River mouth is determined as moderate and recommendation for further studies and activities is to maintain moderate ecological status and try to achieve the good one (concentration of total phosphorus during winter do not exceed 1.0 μmol/l, water transparency is above 3 meters, concentration of chlorophyll a is lower than 6.5 μg/l, F. vesiculosus belt is abundant till 5.25 m depth and macrovegetation belt is abundant till 8.25 m depth), in meantime prevent any site or time specific poor or bad ecological status events. 57 Table C.4. Ecological status in three polygons of the project area indicated by different parameters. Ecological status Polygon 2
Polygon 3 moderate/poor moderate/poor moderate ‐ ‐ moderate Chlorophyll a concentration moderate moderate good Depth limit of Fucus vesiculosus moderate moderate/poor moderate Depth limit of macrovegetation moderate moderate moderate Parameter Polygon 1
Transparency Total phosphorus C.5. Assessment of Hazardous substances in transboundary water bodies C.5.1. Water
Di(2‐ethylhexyl)phthalate (DEPH). The concentration of DEPH did not exceed annual average EQS 1.3 ug/L (maximum allowable concentration are not applicable). The range of results was 0.30 – 0.49 ug/L. C.5.2.Sediments
Alkylphenols and Bisphenol A (BPA). In summary the sampling sites were mostly below LOQ. The LOQ for several samples increase due to matrix interference effect. The highest concentration of Bisphenol A was observed in sediments of the lake Murati – 25.4 ug/kg DW, concentration range at other sampling sites was 11.1 – 4.66 ug/kg DW. Organic tin compounds. Concentrations of organic tin compound for all samples from transboundary sites were below LOQ (for Tributyltin LOQ > 2.7). Polyaromatic hydrocarbons. According to new EQS Directive (2013/39/EU) benzo(a)pyrene can be considered as a marker for the other PAHs as the most toxic PAH. Concentrations of PAHs in the river sediments were less than in lake sediments. Benzo(a)pyrene concentration in Pedele River sediments was 1.6 ng/kg DW, Gauja River sediments on border – 3.9 ng/kg DW, in the lake Murati sediments – 14.8 ng/kg DW. Polybrominated diphenylethers (PBDE) and Hexabromocyclododecane (HBCDD). For results evaluation according to EQSDirective (2013/39/EU) concentrations of certain congeners of PBDEs were counted up. Distribution of PBDEs and HBCDD concentrations in sediments from transboundary sites are shown in Figure C.5.2.a. Concentrations of HBCDD in river sediments were below LOQ <50 ng/kg. 300
HBCDD
ng/kg DW
250
PBDEs
200
150
100
50
0
Gauja R. LV‐EE
Pedele R.
Murāts L.
Figure C.5.2.a. Concentration (ng/kg DW) of PBDEs and HBCDD in sediments. 58 Metals and supporting data of sediments. Concentrations of metals in sediments of transboundary waterbodies are shown in Figure C.5.2.b. Pb mg/kg
Pb, Hg
100
80
60
Hg ug/kg
Cd mg/kg
40
20
0.4
0.2
0
0
Gauja R.
LV‐EE
Pedele R.
Ni mg/kg
Ni, Cu
12
10
8
6
4
2
0
Cd
1
0.8
0.6
Murāts L.
Gauja R.
LV‐EE
A Cu mg/kg
Zn mg/kg
Pedele R.
Zn
120
100
80
60
40
20
0
Murāts L.
B LOI %
LOI, Corg
30
25
20
15
10
5
0
C org %
Al %
Fe %
>250 um
Al, Fe
1.5
<250 ‐ 90 um
<90 ‐ 63 um
<63 um
100%
80%
1
60%
40%
0.5
20%
0%
0
Gauja R.
LV‐EE
Pedele R.
Gauja R.
LV‐EE
Murāts L.
Pedele R.
Murāts L.
C D Figure C.5.2.b. Concentration of (A) Pb, Hg, and Cd; (B) Ni, Cu and Zn; (C) LOI, C org, Al and Fe in sediments and (D) grain size of sediments Mercury, Lead, Cadmium, Copper and Zinc concentrations in the Lake Murati/Muratu sediments were higher than in river sediments. It is well known that clay minerals contain Nickel. In this case Nickel concentration in sediments depends on clay mineral presence in sediments shown in Figure C.5.2.b. (C) as distribution pattern of extractable Aluminium in sediments. All sediment samples analyzed for determination loss on ignition, total nitrogen, organic and inorganic carbon, extractable aluminium, iron and manganese. Sediment samples were sieved for determination grain size of sediments. These parameters show structure of sediments and pollutant sorption ability on sediment surface. C.5.3. Biota
C.5.3.1. Metals in Bivalves
Heavy metals were determined in soft tissues of fresh water Unionidae bivalves. High concentration of Cd (75 ug/kg) in bivalves was found in bivalves from Gauja River on border with Estonia. High average concentration of Hg was found in bivalves from Gauja River on border with Estonia (13.2 ug/kg) and Lake Murati/Muratu (11.1 ug/kg) however mercury concentration in Unionidae mussels did not exceed EQS (20 ug/kg ww) set in Directive (2013/39/EU). 59 Cu*0.1 ug/kg
Pb ug/kg
Cd ug/kg
Hg ug/kg
Zn mg/kg
Hg, Zn
20
Cu, Pb, Cd
100
80
16
60
12
40
8
20
4
0
0
Gauja R.
LV‐EE
Murāts L.
Figure C.5.3.1. The average concentrations of heavy metals in soft tissues of Unionidae bivalves (to wet weight) from transboundary waterbodies C.5.3.2. Fish samples
Hexachlorobutadiene. All measurements of hexachlorobutadiene in wet muscle tissues of perch were below LOQ < 0.25 ng/kg WW, this limit did not exceed EQS for biota – 55 g/kg WW. Hexachlorobenzene. The concentrations of hexachlorobenzene in wet muscle tissues of perch from transboundary waterbodies were 28.9 ng/kg (Gauja River on border) and 21.5 ng/kg (Murāts Lake), this limit did not exceed EQS for biota – 10 g/kg WW. Polybromdiphenylethers (PBDEs). According to EQS Directive (2013/39/EU) for the group of priority substances covered by PBDEs, the EQS refers to the sum of the concentration of congener numbers 28, 47, 99, 100, 153 and 154. Concentrations of PBDE in both fish tissue samples (Figure C.5.3.2.A) exceed EQS value 8.5 ng/kg WW. PBDE ng/kg
DecaBDE ng/kg
350
300
250
200
150
100
50
0
ng/kg WW
0.2
0.16
Gauja R. LV‐EE
TEQ D/F + DL PCB
ng/kg WW
TEQ D/F + DL PCB
ng/kg LW
ng/kg LW
10
8
0.12
0.08
6
4
0.04
0
2
0
Murāts L.
Gauja R. LV‐EE
Murāts L.
A B Figure C.5.3.2. (A) Concentration (ng/kg WW) of Polybromdiphenylethers and Decabromdiphelylether in wet tissues of Perca Fluviatilis muscle; (B) TEQ values (ng/kg) of Dioxins, Furans and dioxin like PCB in fresh muscle tissues (WW) of perch and TEQ values to lipid weight (LW) Hexabromocyclododecane (HBCDD). The concentrations of HBCDD in fish samples from transboundary waterbodies were below LOQ and below EQS value 167 g/kg WW. Chlorinated dibenzo‐p‐dioxins (dioxins), chlorinated dibenzofurans (furans) and dioxin like Polychlorinatedbiphenyls (DL PCB). TEQ values to wet and to lipid weight of fish muscle is shown in Figure C.5.3.2.(B). EQS value (6.5 ng/kg WW) in Directive is set like sum of Dioxin, Furan and dioxin like PCB TEQ values – toxic equivalents according to World Health Organization 2005 Toxic Equivalence Factor. This value was not exceeded EQS in observed perch samples. 60 D. Assessment results of ecological status in transboundary water bodies D.1. Results of assessment of ecological status in transboundary water bodies D.1.1. Ecological status assessment in rivers
The Estonian and Latvian experts assessed the ecological status of four biological elements: diatoms, benthic macroinvertebrates, macrophytes and fish fauna. Physico‐chemical elements such as temperature and the level of nutrients were measured and taken into account just for explaining the results. In general, as required by the WFD the countries apply the principle of so called “one out‐ all out”. The final status of the ecological status of the river is determined by that biological element or physic‐
chemical quality which has been assed as the least quality class. Although this principle is followed in Latvia, the final ecological status was assigned based on the expert’s judgement – as a result of the discussion of the experts who have made investigations in the river water body. This approach was decided because assessment methods (e.g., indicators or indices) of biological elements were new for Latvian conditions therefore the methods needs additional testing to be adapted sufficiently to the local conditions. Estonian experts followed the assessment principle as described already in their national rules for the assessment of the water quality in rivers. Table. D.1.1. The results of ecological status assessment of Estonian (EE) and Latvian (LV) experts from the sampling sites in the transboundary rivers (H‐high; G‐good; M‐moderate; P‐poor quality class). Physico‐
Maro‐
Macro‐
Ecological Fish chemical Transboudary river Diatoms invertebrates phytes status elements water bodies EE LV EE LV EE LV EE LV EE* LV EE LV Vaidava, in Latvia G G H H H H ‐ G ‐ G G G Vaidava, in Estonia G G H H H H G ‐ H G G G Peetri/Melnupe, in Latvia M M H H G H ‐ G ‐ G M G Peetri/Melnupe, in Estonia G G H H H G G ‐ H M G G Pedeli/Pedele, in Latvia M M H M H H ‐ P ‐ G M M Pedeli/Pedele, in Estonia G G G H G G M ‐ H G M G Pedetsi/Pededze, in Latvia ‐ G H H ‐ G ‐ G ‐ G G Pedetsi/Pededze, in Estonia H ‐ H H H ‐ G ‐ H ‐ G Pärlijõgi/Pērļupīte, in Latvia
‐ G ‐ H ‐ ? ‐ P ‐ G H Pärlijõgi/Pērļupīte, in Estonia H ‐ H ‐ H ‐ P ‐ H ‐ P Ujuste/Kaičupe, in Latvia ‐ M ‐ M ‐ ? ‐ G ‐ M M Ujuste/ Kaičupe, in Estonia
H ‐ H ‐ G ‐ ‐ ‐ ‐ ‐ G * based on monthly sampling results Despite of new assessment methods for Latvian experts and slightly different approaches used in assessment of the ecological status in river water bodies, the outcome differs only for two joint sampling sites: 61  Peetri/Melnupe (in Latvian side), where the outcome would be the same if the principle “one out‐ all out” would be also followed by Latvian experts.  Pedeli/Pedele (in Estonian side), where the reason of different outcome is status of fish fauna which were investigated only by Estonian experts.  Another final ecological status would be also concluded for the river Pedeli /Pedele on Latvian side if the principle “one out‐ all out” would be used also by Latvian experts. The different assessment outcome with regard to macroinvertebrates in the river Pedeli/Pedele can be explained by the following reasons:  The river water body has been defined as belonging to different type of rivers (Estonian catchment is small, while Latvian part is already medium thus different values (class boundaries) for ecological quality assessment to be applied by experts (see Annex I)  Different sampling methods used (see chapter B.1.2.)  Different skills to recognise species of macroinvertebrates when samples are treated. The sampling and assessment of macrophytes in rivers is a new method for Latvian experts therefore validation is still needed to be used for reliable assessing the local conditions. D.1.2. Ecological status assessment in lakes
Assessment approach for determination of the final ecological status in lakes was differently implemented by the Estonian and Latvian experts. In Estonia the assessment of ecological status was based on quality status of the following elements: physico‐chemical elements, phytoplankton, macrophytes and benthic macroinvertebrates, which are established in the regulation of the Estonian Minister of Environment. Fish indicators were used for estimation of the ecological status in lakes as well, but since the classification is still in developing they were not used for the final assessment of the ecological status. The final status of the lake’s ecological status is calculated based on so called 2/3 principle, which means that 1/3 of all indicators is allowed to have worse class than the final assessment class. Each indicator has an equal weight and at least 7 indicators have to be used depending on a type of the lake. Indicators and assessed ecological status in the joint sampling sites are presented in the Table D.1.2.a. Table D.1.2.a. Assessment of ecological status in lakes according to 2/3 principle by Estonian experts Indicators Kikkajärv / Murati/ Väike Palkna / Ilgājs Muratu Mazais Baltiņš Type III Type II Type V Hydromorphology Good Good High Physico‐chemical Ptot Bad High Bad elements Ntot Moderate Moderate Bad pH Good High Good Transparency Good Moderate Good Range of metalimnion Good ‐ ‐ Indexes of Chla Good Poor High phytoplankton FPK Moderate Moderate Good FKI High High Good J Moderate Moderate Good 62 Indexes macrophytes of DLS MTX PP CHBR CELE FIAL ISLO ELPO Indexes of benthic T macroinvertebrates H´ ASPT EPT A Ecological status High Moderate High Moderate Moderate ‐ Good High Good ‐ ‐ High High Moderate Good Moderate ‐ ‐ High High Good Good Moderate Good Good Moderate Good Moderate ‐ Good ‐ ‐ ‐ Good Poor Good High Good Good High Good Good In Latvia the final assessment of ecological status in lakes is based on expert judgement taking into account results of: physico‐chemical, phytoplankton, benthic macroinvertebrates and aquatic macrophytes. At first, the assessment of ecological status is prepared based on WFD principle “one out ‐ all out”, then the experts review it and presents their judgement of the water body (see Table 1.2.b). Motivation to use expert judgement is the same: newly overtaken assessment methods from Estonia are not yet sufficiently adapted to the local conditions. The results of the final assessment are the same for the Lake Murati/Muratu where the ecological state is assessed as “moderate” and for the lake Väike Palkna/Mazais Baltiņš – status is “good”. Table D.1.2.b. Assessment of ecological status in lakes according to Latvian expert judgement and according to principle “one out ‐ all out” Kikkajärv/ Ilgājs Murati / Muratu Väike Palkna / Mazais Baltiņš Moderate Moderate Good Macroinvertebrates High Good High Macrophytes Good Good/Moderate Good Phytoplankton Good Moderate/Poor High Good Moderate High Moderate Moderate Good Hydromorphology and chemical elements physico‐
Ecological status according to expert judgement Ecological status according to principle „one out – all out” The difference in the assessment of the lake Kikkajärv/Ilgājs is due to evaluating the importance of the physico‐chemical quality of the lake. As this element has been showing the “moderate” status then Latvia has been evaluating the final status as moderate. The physico‐chemical quality is showing bad quality with regard to nitrogen and phosphorus also in the results of Estonian samples. However the assessment of the existing approach allows assessing the lake of “good” status. Moreover, the values used in this assessment are measurements from spring‐summer season (May‐August in Estonia and 63 August‐September in Latvia) and are evaluated against the physico‐chemical criteria which shall be assessed on annual basis. Thus the project approach might be biased. D.1.3. Ecological status assessment in coastal waters
In Latvia the final assessment of ecological status in coastal waters is based on expert judgement taking into account results of: concentration of chlorophyll a, transparency, total phosphorous, depth limit of Fucus vesiculosus and macrovegetation. The assessment of ecological status is prepared based on WFD principle “one out ‐ all out”, which is then proceeded by the experts review and their judgement of the water body (Table D.1.3.) Table D.1.3. Ecological status in coastal waters according to principle “one out ‐ all out” Ecological status Parameter Transparency Polygon 1 Polygon 2 Polygon 3 moderate/poor moderate/poor moderate Total phosphorus ‐ ‐ moderate Chlorophyll a concentration moderate moderate good Depth limit of Fucus vesiculosus moderate moderate/poor moderate Depth limit of macrovegetation moderate moderate moderate Ecological status according to principle „one out – all out” proceeded by an expert moderate/poor moderate/poor moderate jujdgement 64 E. Conclusions and Proposals E.1. Alignment of the typology of the transboundary surface water bodies in the Gauja/Koiva river basin district E.1.1. Typology of rivers
One of the key differences is the threshold in the lower boundary of the catchment size to be designated as river water bodies. Latvia has set as general principle that the smallest river water body is from the catchment size of 100 km2 which means that small rivers are not recognised in monitoring programmes as well in river basin management plans. The investigations of small river streams performed in Gauja/Koiva project shows that the water quality status monitored in the larger river catchment does not reflect status in the smaller tributaries. Therefore it is recommendable to designate also smaller transboundary river water bodies starting from 10 km2. The following transboundary rivers are proposed to be designated as separate water bodies:  Kaičupe/Ujuste – small river: type IA in Estonia and type 1 in Latvia. The assessment of water quality in 2012 indicates good status in Estonia, but moderate status in the Latvian part of the river.  Pužupe/Puzupe – small river: heavily modified water body in Estonia. In Latvia it would be identified as type 2 river (small potamal river).  Pedele: small and meadium size water body in Estonia. It is recomended to set the river catchment as separate water body in Latvia ‐ type 4, medium size potamal river. The Latvian river water body G237 Mustigi (Pērļupīte) shall be defined as type 1 river – small, rhithral. The proper title for this river water body would be Pērļupīte. The expert team also propose to redefine the D450 Pededze should be classified as type 3‐ medium, rhithral river. The classification of in upper part of the rivers (Ramata and Puzupe) bodies in Estonia as heavily modified is due to the fact that rivers have been drained and at the moment are functioning as ditches. The river Omuļupe which is the source for the river Õhne has not been investigated in Latvia, therefore the proper type and necessity for designation of separate water body in Latvia is uncertain. E.1.2. Typology of lakes
The experts suggest that Latvia could also designate water bodies of surface water below 0.5km2 when it is needed for nature conservation purpose and to ensure harmonised approach in transboundary area. Secondly, the Latvian experts recommend that the importance of the depth factor should be reviewed. It is suggested that characteristics related to stratification are more relevant for the lake ecosystem. The lake Murati is the only designated transboundary lake water body as its surface area is larger than 50ha (or 0.5km2). In the Koiva RBMP ‐ the lake Murati is defined as III type according to Estonian system – stratified lake with medium hardness. During the project, experts have re‐defined it as II type – non‐stratified lake with medium hardness. According the Gauja RBD, the lake Murati is defined as VI 65 type – shallow hard water polyhumic lake. During the project, experts have confirmed the definition of the Murati lakes as VI type. Two other transboundary lakes ‐ Kikkajärv/Ilgājs and Väike Palkna/Mazais Baltiņš ‐ jointly investigated do not meet criteria of being a seperate lake water bodies in Latvia as their surface area is about 20.3 ha and 3.95 ha, respectively. As both lakes are designated as Natura 200 sites the experts recommend them to be designated as separate individual water bodies and to define them as follows:  The lake Kikkajärv/Ilgājs corresponds to type: Estonia: stratified lakes with medium water hardness (III) Latvia: deep hard water oligohumic (clear) lake (9)  Väike Palkna/Mazais Baltiņš corresponds to type: Estonia: light and soft water (V) Latvia: deep soft water oligohumic lake (10) The designation of the lake Mazais Baltiņš as separate water body in Latvia would also provide one example of the lake type 10. This category of lake has been distinguished by the Latvian typology system; however, there has not been designation of any lake of this category as water body so far. The ecological classification for type 10 also has not been elaborated. E.1.3. Typology of coastal waters
The factors and their values used in typology of coastal waters have been harmonised in the Baltic Sea area, thus no need for additional harmonisation task between Estonia and Latvia. E.2. Harmonisation of water quality classification system for transboundary water bodies in the Gauja/Koiva river basin district E.2.1. River water quality classification system
As the result of additional national investigations, the Estonian experts have concluded that there is no need to differentiate river classification for each river type according to the physic‐chemical quality indicators in the Koiva RBD. The current Estonian system defines 2 (BOD5 and Dissolved oxygen saturation level) out of 6 indicators to be different between system A and B. The stricter values which are set for the type B water bodies are also reasonable for type A water bodies. The Estonian experts would also agree to apply Latvian values which for some type of river waters are even stricter. The harmonisation of the indicator values for type A and B for the whole Estonia needs an additional study and discussion between national experts and the Ministry of the Environment. As the key importance for implementing WFD is the definition of the boundaries between high‐good and good‐moderate status then the Table E.1. indicates a proposal for harmonising these boundary values with regard to physico‐chemical quality indicators. These values could be used between countries to assess in comparable way medium size rivers either rhithral or potamal (in case of Latvia) with dark or light (Estonia). 66 Table E.1. The proposed class‐boundary values for physico‐chemical quality transboundary river water bodies in Gauja/Koiva RBD (based on values of Latvian classification system) (for comparision: 1‐ Vaidava at Vastse‐Roosa; Peetri at Leppura; 2 ‐ Pedetsi at Kiviora; Pedeli at Valga) Water bodies Type Indicator High‐Good Good‐Moderate Estonian results 1.Vaidava 2. Pededze/ Pedetsi Medium rhithral (3) Medium, light (IIB) Medium, rhithral (3) Medium, dark (IIA) 1 2
BOD5 mg O2/l 2,0 2,5 1.4 2.0 Ntot mg N/l < 1,8 1,8 ‐ 2,3 1.3 1.3 Ptot mg P/l <0,05 0,05 – 0,075 0.044 0.040 Melnupe/ Medium potamal (4) BOD5 mg O2/l 1.7 1.9 2,0 3,0 Peetri Medium, light (IIA) Ntot mg N/l 2,0 3,0 1.4. 1.0 Pedele/ Medium potamal (4) Ptot mg P/l 0.056 0.079 0,06 0,090 Pedeli Medium, light IIA Regarding the harmonisation of the biological water quality parameters, the situation is very different between both countries. Estonia has established the system for three components: phytobenthos, macroinvertebrates, and fish, just system for macrophytes is in developing stage. As Latvia has not yet established a coherent and comprehensive ecological quality classification system in the country, the results of collected and assessed samples provide an indication for the potential for transfer of the Estonian classification system with regard to similar river types as tested. The transfer of the classification system from Estonia and Latvia could be in terms of the applied indicators and indexes to perform the ecological quality assessment. The jointly tested river types were: Vaidava (Medium rhithral type 3), Pedele and Melnupe (medium potamal rivers, type 4). E.2.2. Lake water quality classification system
Physico‐chemical analyses were carried out with less frequency as requested by the WFD: in Estonian lakes were performed three times during the May‐September so called growing season. In Latvia, samples were collected two times. The results showed rather large variation between the results of the same lake and dates which indicates a need for further testing. Therefore the harmonisation is not feasible. Regarding phytoplankton in transboundary lakes, the expert teams had an opportunity to compare the results from samples from the same lakes taken by the same (Estonian) method in the same day; the same date but with the different (national methods). Results gave the indication that common sampling technique can diminish differences. However, it was also stressed that the qualification of the expert and quality of the work in laboratory might influence the results even more than the different sampling method. Regarding macrophytes, it was recommended that the transect method could be used for lake monitoring in future. The transect method use also other European countries. For the assessment Latvia see it is more beneficial still to use seven (instead of five) point scale for estimation of abundance. During the project Latvian experts tested also indexes and indicators used by Estonian 67 experts. It was concluded that more data are necessary nevertheless, but for the beginning method works well in the lakes tested within the project. Regarding macroinvertebrates, the quality assessments by use of the four indices differed insignificantly regardless that the sampling methods are different. Thus the established Estonian assessment approach for these type of lakes could be transferred to Latvia. As Latvian team did had lake fish experts, then the harmonisation was not possible. In general, it seems that Latvia needs to engadge external fish experts or to allocate sufficient resources to built own capacity to establsih the lake assessment according to the fish fauna. E.2.3. Coastal water quality classification system
Regarding physico‐chemical parameters (total phosphorus and water transparency) and concentration of chlorophyll a, current Latvian class boundaries were slightly modified and supplemented through the analysis of the Estonian scheme suitability for Latvian coast. Class boundaries of phytobenthic parameters were based on the reference from H. Skuja investigations (1924), expert judgment and related literature (Andersen et al., 2004; Krause‐Jensen et al., 2005). The proposed scheme modifies and supplements the current Latvian assessment scheme and gives the background for further LV‐EE coastal water intercalibration work. Table E.2.3. The proposed values for physico‐chemical and biological quality parameters in coastal waters of Gauja/Koiva RBD (type – Gulf of Riga stony coast, waterbody F). Parameter High Good Moderate Poor Bad Transparency, m >5,0 3,0‐5,0 <3,0‐2,0 <2,0‐1,5 <1,5 Ptot, μmol/l <0,6 0,6‐1,0 >1,0‐2,5 >2,5‐8,0 >8,0 Chl a, μg/l <2,0 2,0‐6,5 >6,5‐16,0 >16,0‐40,0 >40,0 Depth limit of Fucus >6,3 6,3‐5,25 <5,25‐3,85 <3,85‐2,1 <2,1 vesiculosus, m Depth limit of >9,.9 9,9‐8,25 <8,25‐6,05 <6,05‐3,3 <3,3 macrovegetation, m E.3. Water quality assessment schemes for the transboundary water bodies in the Gauja/Koiva river basin district E.3.1. River water quality assessment scheme
During the 1st cycle of the river basin management planning in Estonia and Latvia, the approach of “one out‐all out” has been applied meaning that overall quality class is assigned based on the lower quality value of one of the biological, hydromorphological or physico‐chemical elements. While Estonia applied biological parameters and physico‐chemical elements to assess the river water status, Latvia has been mainly using physico‐chemical elements and national saprobity index for assessment of macroinvertebrates. During the Gauja/Koiva project the Estonian team followed the existing assessment scheme, while the Latvian team assigned the final assessment score of the river water bodies’ status based on experts judgement. Moreover, the Latvian experts recommend to keep the existing assessment scheme also in 68 coming years while the evidence and data on different quality elements are strong enough to built the assessment only based on the data of the year when monitoring is performed. Table E.3.1. Final assessment of the status of the transboundary water bodies monitored in the Gauja/Koiva Project Ecological Vaidava Peetri/ Pedeli/Pedele
status Melnupe in LV in EE in LV in EE in LV
in EE
Estonian scheme Latvian scheme Pedetsi/Pededze Pärlijõgi/ Pērļupīte in LV in EE
in LV
in EE Good Good Good Good Moderate Moderate
Good Good Good Good Moderate
Good Ujuste/Kaičupe
in LV in EE
‐ Good ‐ Poor Good
Good
‐ High Moderate
E.3.2. Lake water quality assessment scheme
The lake water quality assessment scheme in Estonia and Latvia is different; however, the Estonian experts are discussing the revision of their national assessment scheme to be used for 2nd river basin management cycle. The existing difference among the countries is also reflected in the final assessment result of the jointly investigated lakes. The final ecological water quality assessment for the Lake Murati/Muratu is moderate regardless which assessment system is used. Even if Estonia would apply ‘one out ‐all out’ principle then due to moderate quality status of phytoplankton, the lake would also need to be assessed as moderate. For other two lakes it is recognisable that Latvian experts assigned the lakes to be in better quality then the existing system of the principle one out all out would be applied. If Estonia would apply ‘one out ‐all out’ principle then due to moderate quality status of fish would also need to be assessed as moderate. The role of the physic‐chemical elements in the final assessment needs to be clarified as well. During the project the samples were taken with other frequency as requested by WFD (every three month), thus the obtained physico‐chemical results are not directly used as criteria for the decision making on the water ecological status in the transboundary lakes. Assessment by the Estonian scheme:  scoring system;  one out ‐all out principle Assessment by the Latvian scheme:  one out ‐all out principle;  based on expert judgement Kikkajärv/ Ilgājs Murati / Muratu Väike Palkna / Mazais Baltiņš Good Moderate Good Moderate Moderate Good Moderate Moderate Good Good Moderate High The experts involved in Gauja/Koiva project support on use of the variety of quality indicators but the final assessment shall be based the integrated approach, not just on technical scoring. As the lakes are not investigated annually then the preferred approach is that the final assessment is defined by the expert judgment instead of the “one out – all out” principle. 69 E.3.3. Coastal water quality assessment scheme
Two important differences exist between the current Latvian and Estonian assessment schemes. Firstly, current Latvian scheme is incomplete containing values only for high and good classes – this did not allow an accurate assessment as all measured parameters were below good/moderate boundary. Secondly, in case of phytobenthic parameters Latvian scheme is significantly more strict than Estonian – if Latvian class boundaries are logically continued, quality would be one or two classes lower. In the new scheme (Table E.3.3.) these boundaries are less strict and the mismatch between the assessed physico‐chemical and biological quality, that appears if using Estonian values, is smaller. In this coastal water quality assessment the expert judgment was more important than strict “one out – all out” principle, because, e.g., Secchi and concentration of chlorophyll a in shallow coastal waters should be assessed regarding depth factor, phytobenthos depth limits – regarding suitable substrate limitation. The overall quality of the investigated coastal waters was assessed as “moderate” with some poor status tendencies in areas next to and above the Salaca River mouth. Table E.3.3. Ecological quality of the coastal waters of Gauja/Koiva RBD assessed by the Estonian scheme, current Latvian scheme and the proposed scheme. Polygon 1 is coastal area above the Salaca River mouth, 2 – next to and 3 – below the river mouth. Physico‐chemical and biological parameters are split separately to highlight important differences between schemes. “*” signifies the uncertainty of quality class as the relevant scheme does not include all classes. Coastal waters ‐ Polygon 2 Coastal waters ‐ Polygon 1 Physico‐ chemical Assessment by the Moderate/ Poor Estonian scheme Assessment by the Moderate or lower* Latvian scheme Assessment by the Moderate/ proposed scheme (Table Poor E.2.3) Biological Good Moderate or lower* Moderate Physico‐
chemical Moderate/
Poor Moderate or lower* Moderate/
Poor Coastal waters ‐ Polygon 3 Biological Physico‐
chemical Biological Good Moderate Good Moderate or lower* Moderate or lower* Moderate* Moderate Moderate Moderate E.4. Recommendations for further investigations on water quality As the results of the joint sampling and assessment of the water quality status in the transboundary water bodies in Gauja/Koiva project, the experts foresee the necessity for the following joint investigations and research work: ‐ To explore the relationship between lakes and rivers with regard to physico‐chemical parameters at inflow and outflow locations; ‐ Due to limited experience with assessment of diatoms and macrophytes, the further adaptation of the tested methods shall be carried out, including intercalibration exercise. ‐ It would be necessary to investigate the impact of urban pollution and agriculture diffuse pollution, impact of storm waters of Valka/Valga on the bordering river Pedele. ‐ There is a need to clarify how important is the water quality of smaller streams and their impact on larger streams. One of the cases could be Pužupe/Puzupe or Ujuste/Kaičupe. 70 ‐
‐
‐
‐
Effect of damming on fish fauna and a impact to other biological components is still uncertain. Currently the water quality final status in Estonia is mainly lowered due to impacts on fish resources, while other elements indicate good or even high status. Drainage impact on biological components – this is also uncertain. For coastal waters recommendation is to use these physico‐chemical parameters only as additional parameters – for example, in determination of reference condition and in case of uncertain determination (values close to class boundaries) of ecological status by biological indicators.Regarding concentration of chlorophyll a, recommendation is to use Estonian assessment system for this indicator, because it is more developed than Latvian and project results show its suitability for Latvian coast as well – indicated ecological status is the same as for other indicators. Proposal for investigative monitoring of priority hazardous substances in water, sediments and biota. It is important to make all 3 environments, on the border Gauja/Koiva (fish/sediments), Pedele (fish/water), Murāts /Murati Lake (fish/water and sediments). Further joint research is necessary for derivation of quality criteria for hazardous substances in different matrixes, especially in sediments. New quality criterias should be harmonizied between countries. E.5. Proposals for the 2nd Gauja/Koiva RBMP to be produced by 2015 The work and results on quality assessment of water bodies in the frame of the Gauja//Koiva project give reason for the following proposals: ‐ The identification of the river and lake water bodies shall be reviewed with regard to transboundary water bodies. Additional water bodies with smaller catchment size should be designated. ‐ Typology of some lakes/rivers needed to be reviewed as indicated in the Conclusions of the project. ‐ Frequency of monitoring shall be sufficient to capture fluctuations in water flows and related pollution loads. 12 times per year is the optimum frequency of physico‐chemical parameters. ‐ Sampling sites shall be coordinated for all analyses ‐ biological assessment, hydromorphology and physico‐chemical sampling. ‐ The general principle for the assessment of the water ecological status called as “one out‐ all out” principle should not be used for all biological elements. It is proposed to use expert judgement together with explanation on the determination of the ecological status for rivers and lakes. 71