Hydrobiologia 386: 55–62, 1998.
© 1998 Kluwer Academic Publishers. Printed in the Netherlands.
55
The typology of floodplain water bodies of the Middle Danube (Slovakia)
on the basis of the superficial polychaete and oligochaete fauna
Ferdinand S̆porka
Department of Hydrobiology, Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, SK–842 06
Bratislava, Slovakia
Received 12 May 1998; in revised form 14 September 1998; accepted 30 September 1998
Key words: floodplain water bodies, typology, classification, ordination, polychaetes, oligochaetes
Abstract
The oligochaete fauna of different side arms and other water bodies in the Slovak–Hungarian stretch of the River
Danube below Bratislava (r.km 1840 – r.km 1807) was investigated. The structure of the oligochaete assemblages
is correlated with the bottom substratum of the river. From data on the composition of the oligochaete fauna,
the clustering and ordination analysis divided the inland delta water bodies into three groups supporting the
river classification of Roux et al. (1982), i.e. eupotamon, parapotamon and plesiopotamon, but parapotamon
and plesiopotamon divided furthermore into two subgroups, which better reflects hydrological conditions, type
of substratum, depth of water bodies and presence of macrophytes. Oligochaete assemblages differ in individual
type of group and subgroups, not only species composition, but mainly quantitative (average abundance).
Introduction
Based on number of species, abundance and biomass the aquatic Oligochaeta are one of the dominant
groups of benthic invertebrates in the main channel of
the Middle Danube, as well as in neighbouring water
bodies in the floodplain. Sixty-one species of Oligochaeta, not including the family Lumbricidae, were
originally recorded in this area (Brinkhurst 1978). A
total of 82 species have now been identified in the river
Danube (Uzunov 1988). Thirty-five species were identified by Hrabĕ (1941) from the Ćilistov branch (r.km
1850–1842), in the floodplain of the Middle Danube.
However this branch was destroyed by the construction of the Gabc̆íkovo water works. In addition, the
Oligochaete fauna of this area was studied by Brtek
& Rothschein (1964), Ertlová (1968, 1970), S̆porka
(1983) and Nagy & S̆porka (1990).
Prior to the construction of the Gabc̆íkovo Hydroelectric Power Station (HPS), the floodplain of
the Slovak-Hungarian section of the Middle Danube
was extensive. The area of the floodplain is constrained within large river dikes on both sides, totalling
22,685 hectares, of which 3,114 hectares made up of
side arm systems connected to the Danube (Holc̆ík
et al. 1981). The typology of floodplain water bodies has been discussed by several authors (see Holc̆ík
et al. 1989), but is primarily based on the hydrological regime. The most detailed classification system
was initially developed for the French river Rhône
(Amoros et al., 1982; Roux et al., 1982; Castella et
al., 1984), based on geomorphological, hydrological
and ecological analyses. The aim of this work was to
characterise these water bodies using long-term results
from research on the oligochaete fauna of the floodplain over the period 1976–1992 before functioning
of the Gabc̆íkovo HPS. After the functioning of the
HPS the hydrological regime has completely altered
(examples of flow regulation-anthropogenic impacts
on floodplain ecosystems summarised in Ward & Stanford, 1995.). Evaluation of the faunal changes which
occurred during changed water conditions in the natural floodplain superimposes all available results from
previous period. Furthermore, the classification of
Roux et al. (1982) was compared with data in the
oligochaete species occurrence.
56
Figure 1. Sampling sites of the Danube River stretch between Dobrohos̆t’ and Medved̆ov, with floodplain and systems of side arms. Dashed
line – the large river dike. Dash and dot line – boundary between Slovakia and Hungary (see Study Area for details).
Table 1. The sampling sites
Site
Locality
Substratum
Depth
(m)
Period of
sampling
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
The main channel (r.km 1840) - shore
The Bodı́ky side arm - shore
The Král’ovská lúka side arm - shore
The Král’ovská lúka side arm - shore
The Král’ovská lúka side arm - shore
The Král’ovská lúka side arm - central parts
The Baka A side arm - shore
The Baka A side arm - central parts
The Baka B side arm - shore
The Baka B side arm - central parts
The main channel (r.km 1815) - shore
The Istragov side arm - central parts
The Istragov side arm - shore
Temporary water bodies
Small side arms
The Is̆pánsky Dunaj side arm -central parts
The Is̆pánsky Dunaj side arm -shore
The Sporná sihot’ side arm
Gravel
Gravel
Gravel+mud
Mud+clay
Clay+mud
Mud
Mud+clay+sand
Gravel
Mud+clay+sand
Gravel+sand
Gravel
Gravel+sand
Gravel+sand
Clay+mud
Clay+mud
Mud
Mud
Clay+mud
0.3–0.4
0.3–0.4
0.3–0.4
0.6–3.6
0.0–2.6
1.8–4.3
0.5–2.0
2.0–3.5
1.5–2.5
1.8–3.8
0.3–0.4
1.1–4.0
0.3–2.0
0.0–1.3
0.1–2.2
1.0–3.5
0.3–2.0
0.1–0.4
1989–1992
1989–1992
1989–1992
1986–1989
1986–1989
1986–1989
1976–1979
1976–1979
1976–1979
1976–1979
1989–1992
1990–1992
1990–1992
1990–1992
1990–1992
1990–1992
1990–1992
1991–1992
Materials and methods
Samples were collected from the the main channel of
the River Danube as well as other water bodies located
in the floodplain between river km 1840 and r. km
1807 (Figure 1, Table 1). Samples from the main channel were taken from the surface of the gravel banks
of the river, and samples were taken from both banks
and the central depth parts of the other water bodies.
Oligochaetes were collected from 1976–1992. Quantitative samples were taken from uncovered bottom
without macrophytes or in interspace between macrophytes. Various equipment was used for sampling the
different types of substrata. A quadrate sampler of the
Sadovski type (Zhadin 1956) was used to sample shore
gravel, a Petersen grab on medial gravel and littoral
mud and grab of the Zabolocki type (Zhadin, 1956)
on medial mud. Thus in the majority of cases, the
57
Table 2. List of oligochaetes and polychaetes from floodplain water bodies of the Middle Danube, Slovakia (abundance of species
expressed on a scale of 6 steps) See Material and Methods
Taxon\sampling sites
POLYCHAETA
Ampharetidae
Hypania invalida (Grube, 1860)
OLIGOCHAETA
Naididae
Chaetogaster cristallinus Vejdovsky, 1883
Chaetogaster diaphanus (Gruithuisen, 1828)
Chaetogaster diversisetosus S̆porka, 1983
Chaetogaster langi Bretscher, 1896
Dero digitata (O.F.Müller, 1773)
Dero obtusa d’Udekem, 1855
Dero sp.
Nais alpina Sperber, 1948
Nais barbata O.F.Müller, 1773
Nais behningi Michaelsen, 1923
Nais bretscheri Michaelsen, 1899
Nais christinae Kasprzak, 1973
Nais communis Piguet, 1906
Nais elinguis O.F.Müller, 1773
Nais pardalis Piguet, 1906
Nais pseudoobtusa Piguet, 1906
Nais simplex Piguet, 1906
Nais stolci Hrabĕ, 1981
Ophidonais serpentina (O.F.Müller, 1773)
Specaria josinae (Vejdovsky, 1883)
Stylaria lacustris Linnaeus, 1767
Vejdovskyella comata (Vejdovsky, 1883)
Vejdovskyella intermedia (Bretscher, 1896)
Uncinais uncinata (Örsted, 1842)
Tubificidae
Bothrioneurum vejdovskyanum S̆tolc, 1888
Ilyodrilus templetoni (Southern, 1909)
Limnodrilus claparedeianus Ratzel, 1868
Limnodrilus hoffmeisteri Claparede, 1862
Limnodrilus profundicola (Verril, 1871)
Limnodrilus udekemianus Claparede, 1862
Moraviodrilus pygmaeus Hrabĕ, 1935
Potamothrix hammoniensis (Michaelsen, 1901)
Potamothrix heuscheri (Bretscher, 1906)
Potamothrix isochaetus (Hrabĕ, 1931)
Potamothrix moldaviensis Vejdovsky-Mrazek, 1902
Potamothrix vejdovskyi Hrabĕ, 1941
Psammoryctides albicola (Michaelsen, 1901)
Psammoryctides barbatus (Grube, 1861)
Psammoryctides moravicus (Hrabĕ, 1934)
Psammoryctides sp.
Tubifex ignotus (S̆tolc, 1886)
Tubifex tubifex (O.F.Müller, 1774)
1
2
4
1
3 4
5
6
7 8
9
1
∗
2
10
11
12
13
1
2
1
1
1
1
14
15 16
17
18
1
4
4
5
3
1
∗
∗
∗
1
1
1
∗
∗
∗
1
∗
1
∗
1
∗
1
1
∗
1
1
1
1
1
1
∗
1
∗
1
1
1
2
∗
2
∗
1
∗
∗
1
1
1
1
∗
2
1
1
1
1
1
1
1
1
1
1
∗
1
1
1
∗
1
1
1
4
1
3
1
3 3
2 4
5 4
4
3
2
1
4
2
2
2
4 2
4
5
2
1 4
3 2
1
2
4
1
3
1
∗
2
∗
2
3
1
2
3
1
2
∗
1
3
1
1
1
1
1
3
4
1
1
5
2
4
4
4
4
1
2
1
1
5
3
1
1
1
2
2
4
1
2
1
3
2
3
2 2
2 3
2
1
3 1
2
1
3
1
2
1
4
1
1
1
2
3
2
1
2
1
2
2
Continued on p. 58
58
Table 2. Continued.
Taxon\sampling sites
Lumbriculidae
Rhynchelmis limosella Hoffmeister, 1873
Stylodrilus heringianus Claparede, 1862
Stylodrilus parvus (Hrabĕ-C̆ernosvitov, 1927)
Enchytraeidae g.sp.
Propappidae
Propappus volki Michaelsen, 1914
Haplotaxidae
Haplotaxis gordioides (Hartmann, 1821)
Glossoscolecidae
Criodrilus lacuum Hoffmeister, 1845
Lumbricidae
Eiseniella tetraedra Savigny, 1826
1
2
3
4
1
4
2
1
4
5
6
7
8
9
1
3
∗
1
2
10
11
12
13
2
2
5
1
1
2
2
1
1
1
2
14
15
16
1
17
18
1
∗
1
2
1
1
2
1
1
1
1
1
1
2
1
1
1
∗ Species occurred only in qualitative samples.
oligochaetes were obtained quantitatively (approximately 400 samples), to a lesser extent qualitatively, i.e.,
from periphyton on various substrates. Samples were
washed through 0.5 mm sieve. Only data obtained
from quantitative samples were used in the data analysis. Because quantitative samples were obtained by
various equipment, categories were recording rather
than an exact number. Six relative abundance categories were used based on proportions of the total fauna
(0: 0%; 1: 0–2%; 2: 2–10%; 3: 10–20%; 4: 20–50%;
5: 50–100%) (Table 2). Pre-processing of the data was
necessary in this case, and original data were standardised with the use of standardisation by range (ranging)
0
according to the formula xij = [xij – minj xij ] / [
maxj xij – minj xij ]. Data transformation is an important step in ecological transformation (Noy-Meir,
1973; Digby & Kempton, 1987).
The sampling stations were compared using clustering and ordination methods with the aid of the
computer programme SYN-TAX 5.0 (Podani 1993).
The hierarchical clustering method used the correlation dissimilarity coefficient on the site x species
frequency matrix, followed by group average clustering (UPGMA of Sneath & Sokal 1973) and minimum
spanning trees (Sneath & Sokal 1973, Gower & Ross
1969). The ordination method used principal component analyses based on the covariance of variables
(centred P.C.A.). From authors which use principal
component analysis for similar purposes I mention
Paoletti & Sambugar (1984), Doledec & Chessel
(1991), Copp et al. (1994).
Results
In the main channel of the Danube and water bodies in its floodplain, 46 species of oligochaetes and
one species of polychaetes were found (Table 2). Of
these, 22 were species of Naididae, 17 of Tubificidae, 3 of Lumbriculidae, and the remained were
Enchytraeidae, Propappidae, Haplotaxidae, Glossoscolecidae, Lumbricidae. Two clustering and one ordination methods were used for characterising the
floodplain water bodies (Figures 2 and 3). From these
analyses, three main types of aquatic habitats were
identified:
I. Main channel, (sites 1, 11). According to Roux
et al. (1982) this channel is classified as eupotamon.
The bottom sediment includes gravel with a smaller proportion of sand. Aquatic macrophytes are not
developed. The dominant species in this habitat included Hypania invalida (Polychaeta) and Stylodrilus
heringianus (Lumbriculidae). The only representative of Polycheta Hypania invalida (Sedentaria, Ampharetidae) occur in the Upper and Middle sections of
the River Danube: in Germany (Kothe, 1968), Austria (Weber, 1964) and Slovak–Hungarian parts of
Danube (Nagy, 1979). It is a ponto-caspian species
and builds cases from substrate particles of clay or
sand. A number of species of Naididae were recorded. The Tubificidae were poorly represented in this
area. From this family Potamothrix moldaviensis and
Moraviodrilus pygmaeus were present. The average
abundance of Oligochaetes was 281 ind.m-2.
59
Figures 2–4. Figure 2. Group average clustering (UPGMA) of sampling sites 1–18 based on the oligochaete list for each site (38 taxa),
following the use of the Correlation dissimilarity coefficient on taxon frequency data. Figure 3. Minimum spanning trees (MST) plot (1–18
sites). Figure 4. Principal component analysis (PCA) ordination of the 18 sampling sites with eigen values.
II. Arms permanently connected with the main
channel, during high water discharges. These are arms
of the parapotamon type (Roux et al. 1982). In the
central zone of arms of this type, the bottom sediment
is formed of gravel. Aquatic macrophytes were present
but restricted to the occasional occurrence of species
of Typha and Phragmites. Dominant family from oligochaetes were Tubificidae. From all types of water,
species richness was highest. Two groups of side arms
were distinguished within this category by biological
and geomorphological criteria.
IIa. subgroup arms situated parallel to the main
channel, with their channels neighbouring to the main
channel (sites 12 and 13) (arms obtained water directly
from main channel). The inlets of these arms have
direct water exchange with the main channel. The substratum of these channels is finer (sand or fine gravel)
than that in type IIb sites. At these sites, the tubificid species Limnodrilus hoffmeisteri and Potamothrix
moldaviensis were dominant. Hypania invalida (Polychaeta) Stylodrilus heringianus (Lumbriculidae) and
species of Naididae (Table 1) occurred in smaller numbers. The average abundance of oligochaetes was 834
ind.m−2 in the central zone and 401 ind.m−2 in the
shore zone.
IIb. subgroup arms prone to inundation, and located further (behind IIa subgroup arms) from the main
channel (sites 2, 8, 10). During higher water level
of the Danube these arms receive water from connected higher site arm systems. In the central zone,
60
Table 3. Selected dominant species of polychaetes and oligochaetes at individual groups of floodplian water bodies (+
dominant; ∗ present; - absent).
Taxon / group water bodies
I.
Hypania invalida
Chaetogaster diaphanus
Nais bretscheri
Nais elinguis
Nais pardalis
Moraviodrilus pygmaeus
Potamothrix moldaviensis
Potamothrix hammoniensis
Potamothrix vejdovskyi
Limnodrilus claparedeianus
Limnodrilus hoffmeisteri
Tubifex tubifex
Stylodrilus heringianus
+
+
+
∗
Taxa total
12–14
+
their bottom is formed by gravel (sites 2, 8). In the
shore zone, the bottom is covered in places with
muddy sediment, with an admixture of clay and sand.
The dominant species included Stylodrilus heringianus, Potamothrix hammoniensis, Potamothrix moldaviensis, Psammoryctides barbatus andLimnodrilus
hoffmeisteri. The number of species of Naididae was
high, but the abundance was low. Hypania invalida
occurred in smaller numbers. The average abundance
of oligochaetes in the central zone was 957 ind.m−2,
306 ind.m−2 in the shore zone.
III. Remnant arms and temporary water bodies.
The sites in this group are only connected to the main
channel during inundation of the floodplain; they are
designated as plesiopotamon by Roux et al. (1982).
The shore zone is overgrown with submergent, emergent and natant macrophytes. The substratum is mud,
with a varying admixture of clay and sometimes overgrown with macrophytes. Dominant families were
Tubificidae. These habitats can also be divided into
two groups of habitats.
IIIa. subgroup permanent habitats near shore silty
(sites 3, 4, 5, 6, 16, 17). These permanent habitats
do not dry out even during the lowest water levels.
Water level in central zone is deepest than IIIb and
was no overgrown with macrovegetation. The dominant species included Potamothrix hammoniensis,
Limnodrilus hoffmeisteri and Limnodrilus claparedei-
IIa
IIb
∗
∗
∗
∗
IIIa
IIIb
-
∗
∗
+
∗
∗
∗
+
∗
∗
∗
∗
+
+
+
7–8
∗
+
+
∗
∗
∗
+
+
∗
∗
∗
+
+
+
+
+
-
20–21
13–28
2–12
anus. Naididae species were rare. The average abundance of oligochaetes in the central zone was 2,170
ind.m−2 , in the shore zone 305 ind.m−2.
IIIb. subgroup temporary habitats (sites 14, 15,
18). In periods of low water these habitats are exposed.
Both the shore and the central parts are overgrown
with either submerged, emerged or natant macrovegetation. The dominant species included Limnodrilus
claparedeianus, Limnodrilus hoffmeisteri. Criodrilus
lacuum occurred in smaller numbers, but was more
frequent than in the other types of arms. The average
abundance of oligochaetes was 2,015 ind.m−2. Racy
position had shore zones of parapotamon side arms
(sites 7, 9). Oligochaeta assemblages is very similar,
although one central zone is in arm subgroups IIa and
second in arm subgroups IIb. Substratum is mud with
proportions of clay and sand. Type of substratum is the
same as arms in group III.
Discussion
Four basic types of sediment: gravel, sand, clay and
mud occur at the bottom of the Danube floodplain.
The type of sediment which is deposited on the bottom of the floodplain water body understudy, depends
on the water flow of the main channel of the Danube,
which influences the hydrological regime of the water
bodies of the floodplain. The structure of oligochaete
61
assemblages is correlated with the bottom substratum
and with the flooding regime of the floodplain water bodies. Oligochaete fauna is found in individual
groups of water bodies, different number of species, abundance and dominant species representation
(Table 3). In plesiopotamon type water bodies there
is a lower richness of species than in parapotamon
type side arms, but the abundance of oligochaetes is
higher. The same results were obtained by Juget &
Lafont (1994). After their results superficial parapotamon exhibits the greatest species richness and nearly
all Tubificidae and Naididae occur there. In Danube
floodplains these differences are also represented in
the subgroups identified. Some species prefer specific
environmental criteria for their existence. Potamothrix
moldaviensis dominates in finer gravel+sand sediment
of parapotamon type side arms (IIa), but is absent
in mud+clay sediment. Stylodrilus heringianus is the
dominant species of gravel sediment in eupotamon and
parapotamon (I, IIb), is present in finer gravel+sand
sediment (IIb), but is absent in the mud+clay sediment of plesiopotamon. Potamothrix hammoniensis is
the dominant species in mud+clay of permanent habitats (IIIa), absent in temporary habitats (IIIb). Our
results with habitat utilization of oligochaetes species
also correspond with Juget & Lafont (1994). Naididae
species Nais behningi, N. bretscheri and N. alpina
and Tubificidae species Potamothrix vejdovskyi and
P. moldaviensis occurred in eupotamon and parapotamon. Species which were found in all habitats are
Limnodrilus hoffmeisteri, L. claparedeianus, Psammoryctides moravicus and Criodrilus lacuum. The
first two species colonise all habitats in Rhône river
floodplain as well. The factors which determine the
distribution of macroinvertebrates are numerous and
interrelated in a complex way (Prenda & Gallardo
1992). According to Brinkhurst (1967) and Lazim &
Learner (1987), the type of food material available
in the sediments is important for the distribution of
tubificid species. According to Cummins (1975) distribution of macroinvertebrates is determined by suitable
food supply, sediment particle size, current, competition for space and predation. At these sites on the
Danube floodplain the main factor determining the
distribution of oligochaetes appears to be the hydrological regime of the main channel. In this type of
aquatic environment, all the other biotic factors are
subordinate to this factor.
Acknowledgements
I wish to thank Dr M. Vranovský for reading the
manuscript and making valuable comments, I am indebted to Dr Ch. Erséus for helpful suggestions with
regard to the English text and Miss R. Reinoldová for
help in collecting and processing the material.
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