Long-term effect of various organic and inorganic nutrient sources on rice yield and soil quality in west coast India using suitable indexing techniques

Abstract

Soil quality (SQ) under any agriculture system is greatly influenced by source of nutrients, type of soil, crop, and their management practices. In this regard, a field experiment was conducted under lowland rice production system for 5 years to assess the effect of nutrient management with organic and inorganic nutrient on soil quality. The nutrient management practices studied were: FYM: farmyard manure (10 t ha−1), Verm: vermicompost (5 t ha−1), GE: Gliricidia and Eupatorium (each 5 t ha−1), PW: Paddy straw and water hyacinth (each 5 t ha−1), SR: Dhaincha (10 t ha−1), RDF-NPK: recommended dose of fertilizers (100:50:50 NPK kg ha−1), and control. The effect of different nutrient management practices on the soil properties, grain yield, sustainable yield index, and soil quality index were evaluated. The nutrient management practices affected the soil properties, rice grain yield, and sustainable yield index significantly. Phosphatase activity, soil organic carbon, microbial biomass carbon, available phosphorus, and nitrogen were selected for minimum data set using principal component analysis. Their corresponding average contribution to the soil quality index was 70.7, 7.92, 8.67, 1.69, and 10.9%, respectively. The soil quality index obtained by integrating the minimum data set and employing non-linear scoring function varied from 0.72 (SR) to 0.99 (FYM) and it was minimum in the control (0.68). The FYM improved the SQ by 28.5 and 45.5% over RDF-NPK and control, respectively. Using organic sources of nutrients under transplanted rice improves the soil quality and sustainability by improving plant growth and soil functions.