Relationships of hydrochemical and biological indicators in the under ice water of Lake Baikal in the spring period. Analysis using correlation networks

Abstract

This study demonstrates that phytoplankton remain the dominant controllers of the chemical composition of dissolved matter in the coastal waters of Lake Baikal during its ice period. Massive planktonic blooms from March to May lead to the accumulation of dissolved biogenic elements and carbon dioxide, thereby maintaining the stable chemical composition of littoral waters. As it was before, the pH of Baikalian waters is regulated primarily by the reversible synthesis of hydrocarbonate and carbonate ions, which is induced by phytoplankton development and the accumulation of dissolved carbon dioxide in algal cells. We show that the littoral area of Lake Baikal near Listvennichny Bay is heavily polluted by easily oxidized anthropogenic organic matter. Biogenic elements produced during the bacterial destruction of this matter may explain the changes in bottom phytocenoses.