Variations in benthic macroinvertebratefauna as indicator of land use in the Ken River, central India

Abstract

Examination of benthic macroinvertebrates in semi-natural, urban and agricultural land use along the highland Ken River in central India reveals a significantly higher density in semi-natural compared with other two landuse. Insects dominate the fauna at semi-natural (90%) and urban locations (93%) compared to agriculture sites (48%) where where annelid share increases to 32%. The semi-natural location characterized by rocky substrate support high relative abundance of Caenidae and Neoephemeridae. Their abundance decreases at urban locations. Brachycentridae, Chironomidae, Glossocolecidae, Nephthydae, Thiaridae and Corbiculidae increased at urban and agriculture locations characterized by small-sized sediments, suggesting important role for substrate also. Ordination shows that the Caenidae and Heptageniidae are characteristic at semi-natural location, Leptophlebiidae, Hydropsychidae, Glossosomatidae at urban while Thiaridae and Chironomidae at agricultural locations. Functionally, the collectors dominate the fauna, as all three landuse, especially large tracts of agriculture, are a continuous source of particulate organic matter (POM) in the river.