Integrated Nutrient Management and Continuous Cropping for a Decade on Soil Properties in a Terraced Land

The effect of integrated nutrient management practices on some important soil properties on terraced land under continuous cultivation after a decade were studied in a field experiment conducted on the experimental farm of the School of Agricultural Sciences and Rural Development under rainfed conditions. Twelve treatments involving N, P and K (NPK) fertilizers, FYM, poultry litter, forest litter incorporated and burned, Azospirillum and Zn either alone or in combinations were applied for 10 years and rice crop cultivated continuously. The organic C content, available K, WHC and per cent aggregation increased significantly in all the treatments whereas, CEC and MWD increased significantly in all the treatments except ½ N+ PK and forest litter burned+ ½ FYM over control. The rate of build up of available N, P and K in various nutrient management practices was estimated to be 0.97 to 24.46 kg N ha^-1 yr^-1 with an average of 13.51 kg N ha^-1 yr^-1, 0.07 to 1.60 kg P ha^-1 yr^-1 with an average of 0.75 kg P ha^-1 yr^-1 and 2.4 to 8.2 kg K ha^-1 yr^-1 with an average of 4.7 kg K ha^-1 yr^-1, respectively. Addition of FYM, poultry litter and forest litter with NPK increased 8.4, 16.7 and 7.6 per cent in aggregates >0.25 mm, respectively as compared to NPK alone.