Shifts in phenology of zooplankton due to climate change

Abstract

Freshwater zooplankton is recognized as sensitive indicator of environmental changes. limate change has already altered abundance, species composition, structure of freshwater zooplankton and the timing of seasonal behavior, events and life-history parameters. In recent decades, due to climate warming, the ice-free period, the biological summer period, the river runoff have increased in Lake Onego. We have identified 5 phenological phases (winter, spring, early summer, late summer, autumn) on the base of the ratio of the main taxonomic groups of zooplankton using discriminant analysis. The date of the beginning and the end of each phenophase, the duration of the phenological phases were determined. omparison of long-term data with current data showed a phenological phases shifts. Early summer phenophase has occurred about 30 days earlier. Autumn phenophase has occurred on average 23 days earlier. Knowledge of phenology zooplankton in Petrozavodsk bay of Lake Onego makes it possible to detail the mechanisms of its functioning and to describe the response to climate change.