Experimental Study in Out-Door Tanks of N and P Uptake by the Aquatic Communities of Lake Kinneret

Abstract

Two trials (1 st Trial-46 and 2 nd Trial-64 hrs duration) experiment in 8 out-door tanks (5 m 3 ) were carried out with similar design: 4 fish densities (0, 1, 5, and 10), 2 densities of zooplankton (high and low) and 4 increasing levels of P and N concentrations of nutrient enrichments. The consecutive changes of N and P concentrations were measured at 3 (Trial 1) and 4 (Trial 2) time intervals. It was found that nutrient uptake of the entire community, which is the differences between initial and final concentrations, was mostly affected by the initial enrichment. The ecological implications are discussed.