Seasonality, biomass and primary productivity of Epipelic Algae in a shallow lake (Neusiedlersee, Austria)

Abstract

AbstractThe seasonal fluctuation, biomass and productivity of epipelic algae in the shallow Neusiedlersee (Austria) were studied from 1981 to 1983. The seasonality of epipelic algae, dominated by diatoms (70 % of the total population), showed a pattern of variable winter growth coupled with a moderate spring and summer maximum. The number of mud dwelling species remained the same as shown in previous studies (LOUB; HUSTEDT 1959a, b), but only two of them, namely Surirella peisonis Pantocsek and Campylodiscus clypeus Ehr., were not abundant. The Diversity Index (H′) varied between 1.0 and 2.86. Specific Biovolumen (x = 47 · 1012 μm3m2) and potential of production (x = 22.75 mg/m2 · h C) showed a positive correlation with the cell number (x = 0.165 · 1010/m2). The average chlorophyll‐a content of 20.51 mg/m2 is comparable to that of the Wadden Sea (COLIJN and DIJKEMA), Schöhsee (HO) and Lake Chilwa (Moss 1979). The average activity coefficient (P/B, mg C per mg chlorophyll‐a and hour) varied between 0.10… 1.93 and the maximum value is only 29 % of that of the phytoplankton. No significant correlation between the algal populations and the ionic concentration of the overlying water could be found because the populations are limited by light intensity.