Oxbow lakes of Lower and Middle Biebrza
Basin as an important element of riverine
valley ecosystem
Małgorzata Słapińska, Dr. Jarosław Chormański
Warsaw University of Life Sciences
Division of Hydrology and Water Resources
Aim of the research
1. Describing oxbow lakes of Lower and Middle
Biebrza Basin:
 morfology,
 habitat state,
 hydrological characteristics.
Aim of the research
2. Comparision of oxbow lakes in the Lower and
Middle Biebrza Basin
3. Examination of dependency between parameters
describing oxbow lake quality and its:
 Area
 Distance from the River
 Connectivity with the River
Methodology
 Visual analysis of morfological features of oxbow
lakes. Remote sensing of lake’s patterns (Infrared
band of Ikonos high resolution image - enhanced to
1 m captured in mid-July).
 Oxbows transparency analysis in ENVI (supervised
classification)
 Hydrodynamical calculation of average flood extend
and frequency in Middle Biebrza Basin
 Analysis of flood extend of Lower Biebrza Basin
(based on the literature)
Study area – Biebrza River Valley
 Biebrza River Valley is located in North Eastern
Poland
 Under protection in Poland – Biebrza National Park
 Natura 2000 site (PLH200008)
 Wetland site of global significance in the frame of
Ramsar Convention
Photo: P. Skórnicki/Agencja Gazeta
Photo: P. Skórnicki/Agencja Gazeta
Biebrza River Valley - significance
 Area of high natural importance, habitat for fauna
and flora – biodiversity
 Undisturbed marshes and fens (river is not
regulated or embanked, low contamination, natural
hydrology)
 Biebrza can be a reference site for comparable
floodplain and fen ecosystems elsewhere in Europe.
Oxbow lakes - significance
 Floog limiting
 Pollution retention
and neutralization
 Valuable habitats
 Recreation
function
Photo: P. Świątkiewicz
Oxbow lakes - threats
 Eutrophication (intensive agriculture, artificial
fertilizers)
 Drainage works
 Flood limitation
 Limitation of extensive agriculture and in
consequence forestation
Formation of oxbow lakes
Oxbow lakes formation - meandring river A – accumulation, E - erosion. (Migoń 2012).
Formation of oxbow lakes
Remote sensing
Lower and Middle Biebrza Basin
Types of oxbow lakes
(according to river connectivity)
1 – permanently connected with both arms (Lotic)
2 – permanently connected with downstream arm
(Semi-lotic)
3 – connected during annual river flood through bank
overflowing (Lentic)
4 – never or rarely connected (e.g. centennial flood).
Oxbow lake permanently connected with
both arms (Lotic)
Oxbow lake permanently connected with
downstream arm (Semi-lotic)
Oxbow lake connected during annual river
flood through bank overflowing (Lentic)
Oxbow lake never or rarely connected
General results of oxbow lakes patterns
analysis
General comparison of Lower and
Middle Biebrza Basin
Comparision of transparency results
from visual method in ArcGIS and
supervised classification in ENVI
Transparency results from supervised
classification in ENVI
Transparency
None
Medium
Small
High
Map of inundation extend for
Middle Biebrza Basin
Conclusions
 Oxbow lakes degradation – most of them are





eutrophic and dissapearing.
Connectivity with the River – most of oxbows are
connected only during floods.
Importance of connectivity with the River.
Different methos of transparency analysis – visual
and automatical supervised classification.
Habitat conditions, Water Framework Directive.
Threats and need of oxbow lakes protection.
Thank you for your attention!
Photo: P. Skórnicki/Agencja Gazeta