The dynamics of biogenic elements in the ecosystem of Lake Arakhley (Eastern Transbaikal Region)

Abstract

This study presents the interannual dynamics of biogenic elements (nitrogen and phosphorus) in Lake Arakhley and compares functioning values of the water ecosystem within different types of intra-annual (seasonal) dynamics of the content of biogenic elements and organic matter in low water years and high water years. The research shows tendencies of increasing and decreasing contents of nitrogen and phosphorus. In low water years, organic matter is autochtonous, whereas in high water years its origin is allochtonous. The concentrations of biogenic elements do not exceed the values of maximum permissible concentration in fishery waters which means that eutrophication has not started. It was found that the dynamics of the content of nitrogen and phosphorus is determined by change in abiotic conditions and rate of biochemical and biological processes. The findings provide better understanding how mesotrophic lakes function.