Soil-site suitability evaluation for major crops grown in the central parts of Prakasam district in Andhra Pradesh, India

Seven typical pedons from central parts of Prakasam district, Andhra Pradesh, India were characterized and evaluated for their suitability to five major crops viz., rice, cotton, chickpea, tobacco and sorghum. Suitability classes of these pedons ranged from moderately suitable (S2) to permanently not suitable (N2) to these crops. Pedon 7 was marginally suitable; pedons 1, 2 and 4 were temporarily not suitable while the pedons 3, 5 and 6 were permanently not suitable for rice. Pedons 5 and 7 were marginally suitable; pedons 1 and 2 were temporarily not suitable while the pedons 3, 4 and 6 were permanently not suitable for both cotton and chickpea cultivation. Pedons 3 and 7 were marginally suitable; pedons 1, 2, 5 and 6 were temporarily not suitable while the pedon 4 was permanently not suitable for tobacco crop. Pedons 3, 5, 6 and 7 were moderately suitable; pedons 1 and 2 were temporarily not suitable, while pedon 4 was permanently not suitable for growing sorghum crop. Shallow soil depth, wetness, organic carbon content, pH and CaCO3 content were the limiting factors in all the pedons of the study area. Texture was found to be limiting in all the pedons except P1 and P2. In addition, alkalinity was also a limiting factor in P1 and P4. However, limitation levels of soil-site characteristics varied from crop to crop. Suitable conservation and remedial measures were suggested to improve the soil productivity on sustainable basis without deteriorating the soil quality. Potential land suitability classes were also suggested based on the possible improvement measures for these soils.