Effect of Stubble Burning on Soil Enzyme Activities in Semi-Arid Region, Türkiye

Post-harvest residue management is widely recognized as an important component of sustainable soil management. Farmers often burn crop residue left in the field after the harvest. In this context, the study was planned to determine the effects of stubble burning on urease, alkaline phosphatase, and catalase activities in soils, as well as on some soil properties. Therefore, in the study, wheat was grown under the conventional tillage in Igdır and the residues (wheat straw) remaining after the harvest were burned in the field. The research was planned as a completely randomized trial with 3 replications, and the size of each experiment plot was 3 × 3 m. In the research, three applications were carried out: stubble burned, stubble not burned and stubbleless not burned. In the experiment, soil samples were collected at 5 min, 1 day, and at 1, 2, 4, 8, and 16 weeks following stubble burning from 0–15 cm soil depth and taken to the laboratory for soil enzyme analyses. As a result of the research; the effects of stubble burning on soil enzyme activities, organic matter, electrical conductivity, aggregate stability and carbonate were found to be statistically significant. It was determined that catalase and phosphatase activities decreased and urease activity increased by burning stubble in soils. The increase in urease activity after stubble burning may be attributed to elevated organic matter availability and enhanced nitrogen mineralization immediately following burning. After stubble burning, the organic matter, aggregate stability and electrical conductivity values of the soil increased, while the carbonate decreased. The study revealed that stubble burning has negative effects on soil properties. Based on the results obtained, this study recommends practices that aim to return crop residues to the soil rather than disposing of them by burning.