Soil tolerates erosion
But not as much as was thought, says a study
SOIL erosion worldwide is threatening our agricultural base. Our farmers are suffering. The maximum amount of soil that an area can lose without affecting its ability to sustain plant growth is the soil loss tolerance value or the T value. Previously the T value for India was set at a uniform 11.2 tonnes of soil per hectare per year. Debashis Mandal and K P Tripathi, from the Central Soil and Water Conservation Research and Training Institute in Dehradun, recently conducted studies to assign specific T values to various parts of the country.
Beginning their study in the Lakshadweep archipelago, Mandal and Tripathi used a model which took into account previously published data on its soil condition and erosion levels. The most important factor was the percolation of water which depends on the soil type. More the water infiltrates, lesser the soil erodes. The other factors were the soil