Long-Term Influence of Fertilizer and Manure Application on Soil Physical Health and Rice Productivity

Abstract

A long-term field experiment conducted during Kharif 2013 evaluated the effects of continuous application of fertilizers and manures on soil physical properties, nutrient balance and yield in a rice-rice cropping system. The treatments included control, varying doses of NPK fertilizers (50%, 100% and 150% RDF), zinc supplementation, farmyard manure (FYM) and biofertilizers such as blue-green algae (BGA) and green manure (GM). Results showed that integrated application of organic and inorganic nutrients significantly enhanced soil physical properties: infiltration rate increased to 8 mm hr-1 in the 100% NPK+FYM treatment compared to 3 mm hr-1 in control, hydraulic conductivity improved to 1.11 cm hr-1 over 0.73 cm hr-1 in control and water stable aggregates (mean weight diameter) reached 2.05 mm versus 1.30 mm under control. Grain and straw yields were significantly higher under integrated management, with peak grain yield of 5065 kg ha-1 recorded in the 150% RDF treatment and 4855 kg ha-1 in 100% NPK+FYM compared to 2350 kg ha-1 in control. The study highlights that long-term integrated nutrient management improves soil health indicators, nutrient use efficiency and sustains higher rice productivity in intensive cropping systems, supporting the adoption of combined organic and inorganic fertilization in India’s rice cultivation for sustainable agriculture. These findings show that organic amendments enhance soil microbial biomass, nutrient availability and crop yields in rice systems over time.