Darwin State Natural Reserve, Borok, p/o Ploskovo, Cherepovetsky raion, Vologodskaya oblast 162543, Russia

Abstract

The author analyses trophical structure of macroinvertebrates inhabiting samples of litter settled (deciduous leaves) in three small lakes with different hydrochemical characters. In acid lake predators and detritovores-collectors are dominant, in slightly acid lake predators, detritovores-filtrators and collectors are the main types. Trophical structure of acid lakes is formed by acid-tolerant species adopted to low pH. In slightly acid lakes circumneutral species are developed. It was shown that trophic structure is formed mainly under influence of biotic factors and is not strongly depended on pH and trophic levels. Vertical distribution of organisms is determined by oxygen regime.