Analysis of long-term dynamics of the plankton community of Lake Baikal

Abstract

Analysis of long-term observations after plankton community of Lake Baikal has demonstrated the tendencies of the increase of the temperature of water for the upper 50 m layer for the last 70 years, of water transparency and chlorophyll a concentration during the season of the open water for the last 40 years. Analysis of the dynamics of the dominant species of phytoplankton has shown the increase of number of non-endemic small-cell species of diatom algae Synedra acus some increase of the number of endemic species Gymnodinium baicalense with simultaneous tendency of decrease of the number of endemic large-cell species of under-ice developing diatom algae. Analysis of dynamics of number of zooplankton has demonstrated that the number of copepods, of endemic under-ice as well as non-endemic year-round rotifers are decreasing, while the number of cladocers, and non-endemic rotifers, developing during end of summer and autumn increases during the last 70 years. We have fulfilled comparative analysis of the results of our monitoring observations of Lake Baikal plankton and the results for other lakes of the World and we are to conclude that the observed trends can be explained by Global, particularly Climate, Change.