Nagaland University Proposes GIS-Based Watershed Management to Combat Northeast Soil Erosion

Researchers at Nagaland University have proposed the use of geospatial technology and watershed management to address growing soil erosion in the hilly regions of Northeast India, following a study conducted in the erosion-prone Siji Watershed of Assam's Gai river basin. The approach uses RUSLE modelling with Geographic Information System analysis to identify areas most vulnerable to erosion and prioritise interventions.

Soil erosion in the eastern Himalayan region is accelerating due to a combination of steep slopes, high-intensity rainfall, deforestation, unscientific land use practices and increasing human interventions including shifting cultivation, mining and infrastructure development. The problem is reducing agricultural productivity, degrading water quality and disrupting the ecological balance of river basins across Northeast India. The Siji Watershed study quantified erosion patterns and sediment transport dynamics using GIS-based modelling to generate spatially specific risk assessments.

The RUSLE method — Revised Universal Soil Loss Equation — integrates data on rainfall intensity, soil erodibility, slope, vegetation cover and land management practices to estimate erosion rates at specific locations within a watershed. By combining this with GIS layers, researchers can identify erosion hotspots, model the effect of different land management interventions and guide conservation investment toward the areas where it will have the greatest impact. The study demonstrated that this approach can be applied practically in the complex topography of the Northeast's hilly terrain.

The researchers recommend mainstreaming GIS-based watershed assessment into land management planning across Northeast state governments, particularly in areas undergoing rapid land use change through road construction, mining and agricultural expansion. Integration with the National Remote Sensing Centre's data resources and collaboration with state forest and agricultural departments would be needed to operationalise the approach at scale. Long-term environmental sustainability in the Northeast, the researchers argue, requires treating soil conservation not as a marginal concern but as a foundational element of regional development planning.

Key figure — Siji Watershed in Assam's Gai river basin used as the study site