Assessment of the impacts of burning regimes on soil quality in the Kakira Sugar Plantation in Eastern Uganda

Abstract

Burning is a common practice used by farmers before harvesting sugarcanes. Fires cause major changes in soil properties in many agricultural ecosystems but little is known about the effects of burning regimes on soil quality in sugarcane. Such knowledge is important for providing a comprehensive understanding of burning regime effects on soil patterns and for planning appropriate long-term agricultural and management in these sugarcane plantations. Changes in soil physical properties and chemical properties were investigated in sugarcane plantations and treatments included a recently burnt (RB), One year after burning (OYB) and a control of unburnt (NB). Soil samples were collected from 0–10 cm and 10-20 cm depths in order to understand the variations in soils properties with depth. The burning regime effect on physical and chemical soil properties were significantly different from among treatment variations while treatment and depth interaction effect was significant for physical and chemical properties except N and total P content in the soil. Significant short-term effects on soil chemical properties but there were no significant effects on physical properties but the soil structure was disturbed. Soil pH increased significantly in the soil one-year post-fire. SOM and Mg level were significantly lower in recently burnt soils and continued to reduce one year after burning. Total nitrogen (N) and phosphorus (P), increased significantly immediately after burning but significantly reduced one year after the burning and concentrations 10-20cm layer were lower than in the 0-10 cm spoil layer. Total potassium (K) decreased immediately after the burning and then increased one year after. Burning in sugarcanes significantly influences physical and chemical properties and therefore need to understand the long term effects of burning should be addressed to guide proper post burning soil management.