Temporal dynamics of photosynthetic primary production of phytoplankton in Lake Kuriftu

Abstract

Wilfred Isaac Asgedom

Photosynthetic productivity of phytoplankton and chemicals of the water column in Lake Kuriftu were studied from August 2005 to April 2006. The light-saturated rate of photosynthesis (Amax), which was positively and strongly correlated with phytoplankton biomass, ranged from 571 to 1136 mg O2 m -3 h -1 . Biomass-specific rate of photosynthetic productivity at light saturation (Pmax) ranged from 18.78 to 33 mg O2 (mg Chl a)-1 h -1 , while the hourly integral photosynthetic production (∑A) which was positively and strongly correlated with biomass and Amax, varied between 0.686 and 1.05 g O2 m -2 h -1 . The factors responsible for the observed spatio-temporal variations in the physical, chemical and biological features of the lake are discussed.