Primary production of phytoplankton community, and concentration of chlorophyll and bacterio-chlorophyll in Lake Smolak (Mazurian Lakeland, Poland)

Abstract

Twenty years post the experimental mineral fertilisation, gross phytoplankton production and chlorophyll concentration in a dystrophic Lake Smolak were analysed. Primary production, remaining at the same level as during the experiment (1971-1974), its seasonal dynamics, ratio of destruction to primary production, and chlorophyll α concentration in water layer 0-3 m in 1993-1995 suggests high photosynthetic activity of the phytoplankton, typical for eutrophic lakes. Thus, changes induced in the phytoplankton by mineral fertilisation seem to be permanent.