Effect of Integrated Soil Management Practices (ISMP) on Soil Properties and Soil Quality Indices in Hot Moist Semi-Arid Red Alfisol Soils of Bangalore Region

Alfisol soils encounter diversity of constraints on account of physical, chemical, and biological soil properties because of climatic and management factors leading to low productivity. This paper summarizes the effect of integrated soil management practices (ISMP) on soil properties and yield of finger millet cropping system in hot moist Alfisol soils. The experiment site is located in Deccan (Karnataka) plateau of Central Eastern Ghats, Bengaluru which was initiated in 1998 in deep sandy Alfisols. Changes in soil properties were assessed after thirteen years using 19 soil physical, chemical and biological parameters. The treatments include 3 main treatments viz., Conventional Tillage (M1), Reduced Tillage (M2), Minimum tillage (M3) and 3 sub-plot treatments viz., 100% N through organic source (F1), 50% N through organic source + 50% N through inorganic source (F2) and 100% N through inorganic source (F3) laid out in a split plot design. The results revealed that ISMP's had a significant effect on soil chemical and biological properties viz., OC, N, P, K, MBC and LC. Among the set of nine ISMP's, the combination of MT + 100% organic N, MT + 100% inorganic N and MT + 50% organic N + 50% inorganic N were found most promising in improving the majority of soil properties. Among integrated soil management practices (ISMP), the combinations of minimum tillage + 100% organic N resulted in significantly higher SQI of 1.54. The average percent contribution of key indicators towards soil quality indices was: pH (8%), available N (12%), available P (33%), available K (7%), available Ca (28%), labile carbon (12%). A significant correlation between yield of finger millet crop and soil quality confirmed the importance of soil quality indicators and indices for achieving sustainable yields in these Alfisol soils.