On the vertical distribution of microorganisms in Lake Baikal during spring deep-water renewal

The vertical distribution of microorganisms during spring deep-water renewal in Lake Baikal was studied. The downward advection of trophogenic waters was found to create conditions for the extensive growth of microorganisms capable of decomposing and mineralizing organic carbon, nitrogen, and phosphorus in deep water layers. These processes occur annually at spring thermal bars near the underwater slope of Lake Baikal, whereas in its pelagic zone. the deep intrusions of waters rich in organic material are observed only in the years when enhanced deep-water renewal is accompanied by a high spring yield of phytoplankton.