Bathymetric distributions of chironomid communities in ten French lakes: Implications on lake classification
Verneaux, V.; Aleya, L.
published: May 26, 1998
ArtNo. ESP141014202004, Price: 29.00 €
Biological typology of lakes is commonly based on the analysis of profundal chironomid communities (Thienemann 1913, Brundin 1949, Saether 1979, Wiederholm 1980). In this study, ten French lakes were characterized using Brundin's and Saether's schemes of lake classification. The results showed that all these lakes were "Chironomus anthracinus" or "eutrophic" lakes, even though environmental factors (chiefly oxygen concentration and the amount of organic matter in the sediment) differed from lake to lake. We also compared the classification of these lakes as mentioned above with a new type of classification based on the analysis of bathymetric distribution of chironomid fauna. Taking the bathymetric distribution of chironomids into account seems to be more informative than relying only on an analysis of profundal communities. The lakes were classified according to bathymetric modifications of their communities related more to oxygen and organic matter than to chlorophyll-a concentrations. As these results were in disagreement with the trophic typology proposed by Saether (1979), we propose a hypothesis to explain the differences between the two types of classifications based upon the factors influencing chironomid communities.