Assessment of Soil Degradation and Large Scale Soil Mapping Using GIS: A Case Study of Village Ramagarh from Purna Valley, Maharashtra

The importance of soil-physiographic relationship in soil survey and mapping provide a fair understanding of variability across the landscape needed for sustainable agricultural planning. Keeping this in view the swell- shrink soils of the Ramagarh village of Purna valley in Amravati district, Maharashtra in semi-arid region of central India were studied for their morphological, physical and chemical characteristics and soils were mapped at 1: 8000 scale in geographical information system (GIS) platform. The soils of Ramagarh village are very deep, dark grayish brown to very dark grayish brown in colour, clayey in texture and exhibits medium, moderate, sub angular blocky structure in the surface layers and the subsoil horizons have medium, weak to strong angular blocky structure. Soils are alkaline in reaction, calcareous in nature and low to medium organic carbon content. The pH, CaCO3 and exchangeable sodium percentage (ESP) increase with depth in all the soils. Because of high smectitic clay content and ESP down the profile, these soils have impeded drainage and show ponding of water in the rainy season. The soils of the uplands are classified as Sodic Haplusterts and low land soils belong to Typic Haplusterts category at sub group level. The study indicates that the soils are sodic chemically degraded in 18.2% area of the TGA of the village. The higher ESP was related to corresponding decrease in exchangeable calcium and increase in exchangeable magnesium.