15. Assessment of Potassium Nutrient Balance in Agricultural Farming System: A Pathway to Sustainable Production of Crops

Sustainable soil nutrient management is essential for achieving food security, ecosystem sustainability, employment generation and economic development. Soil gets nutrients in particular potassium (K) from various sources like organic and inorganic sources. In recent times, inorganic sources account for a larger share of flow and stock of nutrients in the soil and cause environmental pollution. The dynamic nutrient budget tool was used to assess the stock of soil K nutrient by the inclusion of inflow and outflow of K sources from 1990–1991 to 2012–2013. We used cross-sectional data of inorganic fertilizers, organic manure, area under various crops and their productivity. Per ha K outflow was significantly higher than per ha K inflow in most regions of the Tamil Nadu State. It resulted in negative K balance. The static model was initially included to find out net inflow, i.e. nutrient balance but empirical estimation gives a negative value which becomes unable to calculate stock of K in the same period. It infers that amount of K addition to the soil in the Tamil Nadu State was low, while the area under nutrient intensive crops had significantly increased. Hence, it is suggested that more awareness on balanced K nutrient application need to be created among the farmers and to formulate appropriate policy measure in sustainable production and distribution of K fertilizers to the farmers.