Statistical methods for analysis of the species structure of communities (by the example of the riverine macrozoobenthos)

Abstract

A system of indices that estimate different statistical patterns of communities’ taxonomic structure organization such as nestedness, turnover, and coherence in species cooccurrence is considered. On the basis of data of hydrobiological monitoring, the statistical significance of the structural determinancy of ecosystems is analyzed by means of randomization procedures and standard null models. The comparable efficiency of different indices and methods of their estimation are discussed by the example of the macrozoobenthos communities in small rivers of the Lower Volga basin. The reason for the insufficient adequacy of methods applied for watercourses with a strongly pronounced longitudinal gradient of landscape features is analyzed. The dependence of statistical conclusions on detailing of the initial data and level and scale of aggregation of separate blocks of the ecosystem is shown.