Optimization, Niche and Neutral Mechanisms in the Formation of Biodiversity

Abstract

Today the main scientific belief on the mechanisms for the formation of community structure is the concept of ecological niches and the " neutral theory " . We consider processes of diversity optimization at the levels of populations and ecological communities as an additional type of the mechanisms. Basing on the principle of optimal diversity a scheme for cooperative effect of different mechanisms of formation of the communities species structure is proposed: 1 ‒ number of species and their niches width is primarily determined by the processes of diversity optimization, according with an available resources levels and the degree of environmental stability; 2 – these parameters are modified by other mechanisms during the formation of the species composition, depending on the ratio of the environmental " richness " and stability: ‒ neutral mechanisms work primarily in very " rich " or very stable environments;‒ niche mechanisms work primarily in the environments with medium values of the " richness " and stability, rather when the number of niches with optimal width, which divide the available range of the resource parameter and the number of species that may exist on the available quantity of the resource, are approximately equal;‒ " abiotic filters " work primarily in poor, severe, or extremely unstable environments.