Land Degradation Assessment Using Geospatial Techniques

Abstract

Land degradation is a thoughtful threat involved in reducing area and productivity of 13.4 billion ha in the global cultivable land. The genesis and distribution of different types of land degradation processes depend on climate, topography, vegetative cover, parent material (salty or acidic), and groundwater (saline, sodic, or heavy metals/metalloid). Above all, human-induced degradation of land has been exaggerated recently. These changes in land degradation can be monitored and assessed through geospatial techniques such as remote sensing (RS) and geographic information system (GIS) with fine spatial and spectral resolution imageries. The advanced techniques such as microwave, hyperspectral, and proximal ground-based sensor data with multivariate statistical algorithms have increased the efficiency of classification and mapping of degraded lands. The values of different parameters extracted from thematic map of the terrain, surface, hydrology, and spectral ratio indices of multispectral, hyperspectral images are used as an input parameter for the generation of a digital soil map. The digital soil map with seasonal/temporal variation (possible with fine temporal resolution) conveys detailed information regarding the study of changes, characterization, causes, protection, and reclamation of the land degradation processes. The method of real-time monitoring and assessment of land degradation using RS/GIS techniques is cost-effective, fast, and accurate and indicates land/resource management quickly to secure the food, water, and environmental security. This chapter summarizes the comprehensive understanding of the extent, type, cause of land degradation processes, and indicators of land degradation as well as assessment and monitoring of such through advanced remote sensing techniques.