Distribution of benthic macroinvertebrates in relationship to plant roots, sediment type and spatial scale in fishponds and slow streams

Abstract

The distribution of benthic macroinvertebrates was studied in relation to the sediment type, presence of macrophyte roots, and oxygen in the sediment at several field sites in Southern Bohemia, Czech Republic. The influences of other environmental factors such as water depth and macrophyte species were also observed. In general, the benthic macroinvertebrates were aggregated with both sediment quality and plant roots, while the other environmental factors did not have any influence. Oligochaetes were more abundant in the vicinity of the roots regardless of the sediment type, while chironomid distribution corresponded more closely with the sediment type. More animals occurred quite regularly close to the plant roots than further away, when the root-zone of the plant was sampled directly. When random sampling in the macrophyte cover was used, no relationship of animal numbers to the presence of plant roots was observed.