Biotic interactions in freshwater and effects on community structure

Abstract

The freshwater community structure, especially in the open waters, is not only the result of abiotic environment, but preeminently of biotic interactions, like predation and competition for resources. Many examples of catastrophes of greater or lesser extent are given, such events may occur, especially in immature ecosystems, following the disappearance of a species or the introduction of a new one. It is stressed that community structure modifies the abiotic environment.

Limiting factors of limnetic communities are considered and the risks of their modification by man are discussed.

The author concludes that basic research in hydrobiology can assume an importance far beyond its scientific interest.