Intensive production systems in India characterized by heavy removal and inadequate replenishment of nutrients resulted in depletion of soil nutrient reserves and multiple nutrient deficiencies. For sustaining the crop productivity and to restore the soil fertility, there is a need to arrest this depletion. Clear understanding of crop nutrientbalance is pre-requisite. There were many attempts to examine the potassium mining at individual plot level, long-term fertiliser experiments, state level and country level. In most of these reports, fertiliser inputs and crop removals were only considered, thus resulting in the large-scale negative K balances in Indian agriculture. In agro-ecosystem, K is contributed by many sources like animal manure, crop residue, compost, rice burning residue, irrigation water and rain etc. Similarly, besides crop K removal, K is lost to deeper layers by rain or irrigation water by leaching. By considering all these inputs and outputs, the holistic K balance in Indian agriculture is about 3 mt per year. This total negative balance is reduced by considering area under conservation agriculture (about 4 to 5 mha), green leaf manuring like gliricidia and other non-conventional sources of potassium being used in Indian agriculture, which reduces the overall negative balance of K to 2.8 mt annually in Indian agriculture.
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