43 The influence of habitat conditions on the plankton in the Białe oxbow lake (Nadbużański Landscape Park) Limnological Review (2013) 13, 1: 43-50 DOI 10.2478/limre-2013-0005 Introduction he greatest advantage of the Nadbużański Landscape Park is the maintained Bug River valley, an area where the meandering river forms numerous oxbow lakes. he functioning of small water bodies depends on many environmental parameters, e.g. the concentrations of nutrients – phosphorus and nitro- gen – mineral compounds, temperature, pH and water transparency. Given the small surface area and depth of these lakes and the related small volume, as well as the large diferentiation of the morphometric condi- tions within the water body (depth, substrate type), the parameters listed above are characterised by large variations in time and space (Joniak 2009; Dembows- ka 2011). he variability of morphometric features and physico-chemical parameters afect the development of speciic types of hydromacrophytes, the commu- nities of which play in turn the habitat-making role, changing both the physical conditions (water trans- parency) and the chemical conditions (circulation of nutrients) and creating the substrate and refuges for aquatic organisms (Schefer 2001). he substantial dif- ferentiation of higher vegetation communities within the reservoir can be seen distinctly in oxbow lakes, particularly those that remain unchanged by human activity (the absence of hydro-engineering and ishery facilities) and are located in river valleys with a natural hydrological cycle (Urban and Wójciak 2006; Strzałek and Koperski 2009). he enhancement of the species- speciic diferentiation of oxbow lakes is favoured by their usually elongated shape, the presence of numer- ous side bays, the accelerated succession manifested by the shallowing and progressive terrestrialisation of the branches, as well as – in the case of many meander lakes – large variations in the water table levels and/ or a periodical contact with river waters (Junk 1997). In the national and foreign literature, data con- cerning oxbow lake plankton can be found; however, in most cases, the results of these analyses treat a water body as a whole, unifying the spatial diferentiation to one designated point which is usually a fragment of the bottom uncovered by vegetation (Izaguirre et al. 2004; Jezierska-Madziar 2005; Wojciechowska et he inluence of habitat conditions on the plankton in the Białe oxbow lake (Nadbużański Landscape Park) Agnieszka Pasztaleniec 1 , Maciej Karpowicz 2 , Malgorzata Strzalek 3 1 Department of Monitoring and Freshwater Assessment Methods, Institute of Environmental Protection – National Environmental Institute, Kolektorska 4, 01-692 Warsaw, Poland; e-mail: paszta@ios.edu.pl (corresponding author) 2 Department of Hydrobiology, Institute of Biology, University of Bialystok, Świerkowa 20B, 15-950 Białystok, Poland 3 Department of Ecology and Environmental Protection, Siedlce University of Natural Sciences and Humanities, Prusa 12, 08-110 Siedlce, Poland Abstract: he spatial diferentiation of the physico-chemical parameters (Kd PAR , pH, DOC, nutrient concentrations) and plankton communities (phytoplankton, Crustacea) was considered in the system: the water column without macrophytes, pleustophytes – lemnids (duckweeds) and hornwort Ceratophyllum demersum. It was demonstrated that at the study sites diferent habitat conditions occurred, which were related to the macrophyte assemblages. he highest values of the phytoplankton biomass and the greatest algal biodiversity were found in the site without vegetation, in both species-speciic and functional terms. Zooplankton, dominated by Copepoda, reached the greatest density and species diversity at the Ceratophyllum site. Despite the substantial diferentiation of habitats, the plankton diversity was quite low. Key words: plankton, oxbow lakes, Ceratophyllum demersum Unauthenticated | 212.33.72.157 Download Date | 8/5/13 11:23 AM