Submerged macrophytes as bioindicators of environmental conditions in shallow lakes in eastern Poland

We investigated the responses of submerged macrophytes to environmental conditions in shallow lakes to evaluate the role of macrophytes as bioindicators of water quality and anthropogenic disturbances (such as eutrophication) of shallow lake ecosystems. The studies were conducted on a group of ten shallow lakes situated on the area of Polesie Lubelskie (eastern Poland). The lakes represented five types of macrophyte communities, Chara- Stratiotes-, Myriophyllum-, Potamogeton- and Ceratophyllum-dominated. The total biomass of macrophytes and their distribution were significantly negatively correlated with the trophic status of the lake. Principal component analysis confirms the separation of the lakes with regard to trophic status and macrophyte species richness and biomass. The results of the Monte Carlo permutation test (RDA analysis) indicated the significant effect of Secchi disc depth, pH, conductivity, chlorophyll-a, Ptot, P-PO4, N-NO3 and N-NH4 on the biomass and distribution of submerged macrophytes in the lakes.Macrophyte assemblages showed visible negative changes of their species diversity and biomass through the human induced eutrophication process. Their diversity is the combined effect of environmental conditions specific for a lake ecosystem, thus macrophytes have a crucial role in biomonitoring studies of shallow lakes