Seasonal development of a turbid hydrothermal lake plume and the effects on the fish distribution.

Measurements of the suspended particle concentration in a lake demonstrate the presence of a turbid hydrothermal plume. The plume, generated from a warm source develops upward carrying a suspension of particles from the bottom. It is found that the vertical structure of the plume depends on the stratification of the water column, which in turn depends on the seasonal meteorological conditions. During the stratified period of the lake, the plume is constricted to the hypolimnion zone. At the beginning of the summer season, the plume reaches the bottom of the metalimnion meanwhile at the end of this season the plume does not. In the mixed period of the lake, the plume develops in the whole water column and reaches the surface of the lake, where particles accumulate and spread around the center. Measurements of the vertical fish distribution in the stratified period show that the plume can constrict the fish habitat due to an increase of suspended particles transported by the plume.