SOIL EROSION MODELLING IN LOKTAK LAKE CATCHMENT : AN INTEGRATED APPROACH

Abstract

Land degradation due to soil erosion by water is a widely recognized problem. It is a serious environmental problem affecting areas of different landscapes and land use . Assessment of soil erosion from catchment area is required for effective watershed planning, management and soil-water conservation. The process of soil erosion is influenced by spatial and temporal characteristics of input, i.e. rainfall and by the controls exerted by land surface.. Such control include elevation, slope, soil cover and vegetal cover. The knowledge of spatial and temporal variations of inputs used in distributed modelling can enhance the capabilities to model these processes. The integration of a distributed soil erosion model with the spatial data handling capabilities of a Geographic Information System (GIS) provides desired distributed information about the soil ersoion. In addition the use of remote sensing data provides a viable alternative for collection and interpretation of terrain data at a regular. interval. The present work deals with the western catchment of the endangered and ecologically fragile Loktak Lake in the Manipur state of India. The lake, considered as the lifeline for the state, has been facing a series of problems in the recent few years, one of the main reasons of which have been identified as extensive soil erosion in the upper catchment. It has been proposed to suggest a suitable soil erosion model for the region, which incorporates the local conditions and would efficiently estimate the erosion rate from the catchment.