River Habitat Mapping: are Surface Flow Type Habitats Biologically Distinct?

Abstract

Current river habitat mapping uses several methods, many relying on descriptions of habitat units based on depth, velocity, substrate and water surface patterns. Water surface patterns are controlled by local geomorphology and hydraulics and can be remotely sensed, if surface flow type habitats are physically and biologically distinctive this may provide a faster surveying method. Six UK lowland rivers were investigated, surface flow types were mapped and the physical characteristics of each habitat unit recorded. Samples of benthic macroinvertebrates were taken from representative units and quantified. The results show that habitat mapping, using surface flow types in small lowland streams, is viable and that those habitats have some degree of physical distinctiveness. Analysis of benthic macroinvertebrate communities shows that there is some association with mapped habitats, and therefore are potentially biologically relevant