Development ofPotamogeton pectinatus in heated water of the Patnowskie Lake

The rate of individual development and biomass of two subpopulations ofPotamogeton pectinatus were measured in the heated and cool zones of the Patnowskie Lake in central Poland.P. pectinatus from the heated zone terminated its vegetation six days earlier than individuals from the cool zone. The rate of plant development and individual plant size from both stands were compared during their whole seasonal life cycle. At the final stage of development, the individuals from the heated zone were smaller than those from the cool zone. The data obtained from the measurements were treated by statistical analysis using the MANOVATEST.