The Synergistic Impact of Climate Change and Anthropogenic Management on the Lake Kinneret Ecosystem

Abstract

Anthropogenic and natural processes caused significant changes in Lake Kinneret and its drainage basin ecosystems. Climate change of warming and dry-ness induced a decline in the lake water level. Changes in the composition structure of the phytoplankton assemblages were enhanced by the decline of nitrogen availability resulting in reduction of Peridinium and enhancement of Cyanobacteria. Increase of the phosphorus availability enhanced Chlorophyta and diatoms. Nutrient export from the Hula Valley to Lake Kinneret is discharge-dependent. The external input decline of organic nitrogen and total dissolved phosphorus is due to anthropogenic achievements. Nitrogen decline and slight increase of phosphorus in Lake Kinneret were followed by Peridinium decline and increase of non-Peridinium algae. The resulting change of food-web structure and water quality in the Kinneret was a shift from phosphorus to nitrogen limitation, which enhanced cyanobacteria.