Diversity of soil dwelling collembola in a forest, vegetable and tea ecosystems of Assam, India

Abstract

Land use change has a great impact in determining the diversity patterns of soil fauna. Adoption of any land use pattern significantly affects the soil structure and its physico-chemical characteristics, which often leads to the loss of biodiversity. Considering the collembolans as the key organism in the indicator shopping basket of soil environment, the response of Collembola communities under three different land uses represented by forest, vegetable and tea ecosystems was studied. Collembolans were sampled at monthly intervals using Tullgren funnel and identified by standard taxonomic keys. Diversity analysis and soil chemo-edaphic factors were studied to establish the impact of different land uses on Collembola communities. Five genera of Collembola viz., Cyphoderus, Entomobrya, Isotoma, Folsomia and Hypogastrura were recorded from the forest ecosystem whereas Folsomia was completely absent in vegetable ecosystem and the tea ecosystem soil was devoid of both Folsomia and Hypogastrura. Seasonal diversity and density of Collembola were recorded to be higher in the forest ecosystem indicating the presence of relatively stable habitats as compared to vegetable and tea ecosystems showing relatively disturbed habitats. Correlation studies between different chemo-edaphic factors and collembolan population revealed that the moisture and organic carbon content of soil had significant positive correlation during all the four seasons in all the ecosystems studied. Higher adoption of mechanical and chemo-centric agriculture depletes the available resources of the soil and makes it less habitable and conducive for the growth and sustenance of collembolans in vegetable and tea ecosystem as compared to forest. Appropriate landscape planning, land management strategies and developing proper methods of land use practices may pave the way for the improvement of collembolan diversity at landscape level.