Effect of Burning and No-Burning on Soil Properties in Guinea Savanna of Nasarawa State

This study examines the short-term effects of annual burning and no-burning management on soil chemical and physical properties in the guinea savanna zone of Nasarawa State, located in Nigeria's North Central geopolitical zone. Bush burning is a widespread land preparation practice in the savanna belt, and its effects on soil properties, particularly organic matter, nitrogen, and microbial activity, have significant long-term implications for soil fertility and land productivity. Using a comparative field design, paired burnt and unburnt plots were established in three villages in Lafia and Doma local government areas. Soil samples were collected before burning, immediately after burning, and three months after burning at 0 to 10 cm Soil Scienceh and analysed for organic carbon, total nitrogen, available phosphorus, soil pH, bulk density, and microbial biomass. Findings revealed that immediate post-burn soils showed a transient increase in pH and available phosphorus due to ash alkalinity, but organic carbon and total nitrogen declined by 35 and 28 percent respectively compared to unburnt control plots. Microbial biomass carbon was reduced by 52 percent immediately after burning and had only partially recovered by the three-month sampling. Bulk density increased significantly in burnt plots due to the loss of surface organic matter and disruption of soil aggregates. The study recommends alternatives to annual burning including mechanical vegetation slashing and mulching to preserve soil organic matter and microbial activity in Nasarawa State savanna farmlands. Keywords: bush burning, savanna, soil properties, organic carbon, Nasarawa State.