Soil Degradation

Two papers in a Special Section of Current Science deal with the problem of degradation in some Vertisols of the Deccan Plateau. These are indeed original research findings of the authors. The degradation has been explained as an outcome of selective removal of calcium from exchange complex in the upper strata of the soil profile and its replacement by sodium ion released by weathering of certain minerals. The process is mediated by rainwater that percolates down the soil profile. However, to the best of my knowledge, such a phenomenon is not obvious in numerous other soils of the vast semi-arid tropical soil (SAT) in the country.