Deposition Rate of Lake Sediments Under Different Alternative Stable States

Sediments of five shallow lakes in Polesie Lubelskie region (Eastern Poland), representing a wide range of nutrient concentration, were dated by Pb-210 method and reliable age-depth models were constructed. These models were a base for studies of relationship between status of lake biocenoses and rate of sedimentation in the lakes. The sedimentation rate does not depend on ecological status of studied lakes. The highest mean sedimentation rate was found in phytoplankton-dominated (Lake Syczyńskie) and phytoplankton-macrophyte-dominated (Lake Sumin) lakes. Macrophyte-dominated lakes represented intermediate values of deposition rate. Lake depth, area and hydrology are more important factors controlling sedimentation rate. The sedimentation rate was rather stable or changed over the time, depending on human management in the lakes' drainage basins.