Experimental Study of the <i>Aphanizomenon ovalisporum</i> Response to Nitrogen Fertilization in the Sub-Tropical Eu-Meso-Trophic Lake Kinneret (Israel)

Abstract

First record of a bloom of filamentous-heterocystous nitrogen fixer cyanobacterium, Aphanizomenon ovalisporum , was documented in the summer of1994 inLake Kinneret (Israel). Awareness of such a bloom outbreak was predicted earlier based on documentation of Nitrogen deficiency and Phosphorus Sufficiency developed conditions. The concept of Nitrogen fertilization aimed at suppression of Nitrogen fixers Cyanobacteria was worldwide discussed and successfully implemented, but mostly in temperate oligotrophic lake ecosystems. This paper presents an experimental testing of this concept by additional Nitrogen. The results of the present study did not verify this hypothesis probably related to the ecological differences between Kinneret and the temperate ecosystems and using only one factor (Nitrogen) to test it.