Geomorphological Analysis for Inventory of Degraded Lands in a River basin of Basaltic Terrain, Using Remote Sensing Data and Geographical Information Systems

Abstract

In recent years, the use of remotely sensed data and Geographic Information System (GIS) applications has been found increasing in a wide range of resources inventory, mapping, analysis, monitoring and environmental management. Remote sensing data provides an opportunity for better observation and systematic analysis of terrain conditions following the synoptic and multi-spectral coverage. In the present study, the geomorphological analysis reveals that various denudational and depositional landforms have been analysed and mapped. The soil depth ranges from extremely shallow in isolated mounds to very deep in the pediplains. Based on the slope gradient, morphometry, soil depth, vegetation cover and image characteristics of standard FCC imagery of IRS-1D LISS-III data, fbur categories of eroded lands i.e., very severe, severe, moderate and nil to slight have been identified and mapped. The integrated analysis of slope, geomorphology and degraded lands layers in GIS revealed that the pediplains, rolling plains and subdued plateau are associated with very severe land degradation and accounts for 6.05%, 3.85% and 3.47% of total area respectively. The analysis of percentage of degraded lands at geomorphic sub unit level indicates that severe land degradation process is dominant in the dissected ridges, isolated mounds, escarpments and plateau spurs. The remote sensing data and GIS based detailed geomorphological and degraded lands analysis ensure better understanding of landform-eroded lands relationship and distribution to assess the status of land degradation at micro geomorphic unit for reclamation, geo-environmental planning and management. Similar study also helps in the areas of natural resource management, environmental planning and management, watershed management and hazards monitoring and mitigation.