Short-Term Impact of Rice Residue Burning and Management on Soil Nutrients and Crop Yield in a Rice-Wheat Cropping System

Stubble burning is a prevalent practice in the rice-wheat cropping systems of the Indo-Gangetic Plains, done primarily for rapid field clearance between paddy harvest and wheat sowing. This two-year field study conducted in Dakshin Dinajpur, West Bengal, evaluated the impact of short-term residue burning on some soil chemical properties - soil pH, available nitrogen, available phosphorus, available potassium and wheat yield, under both conventional tillage and zero tillage systems. Eight treatments were evaluated in a randomized block design at three soil depths. Results revealed significant differences among the treatments across the soil profile. Residue burning caused a slight, temporary increase in topsoil pH but significantly reduced available nitrogen by 12-14% and available phosphorus by 27-47% across all profiles, primarily due to nutrient volatilization and suppressed microbial activity, while potassium levels were only slightly affected. Wheat yields declined sharply under both conventional and zero tillage burning treatments compared to residue retention or incorporation. In contrast, conservation agriculture approaches maintained higher soil fertility and wheat yield. The highest grain yield of 5.64 t ha⁻1 was recorded in T2, which corresponded to the conventional tillage with residue incorporated treatment. Hence, even under a short-term trial, these findings have shown the detrimental effects of residue burning, recommending conservation agriculture practices that retain or incorporate residues to sustain soil fertility and crop productivity.