Investigation of Soil Compaction Effects of Tractor Operations on Crop Yield in Niger State

This study investigates the effects of tractor-induced soil compaction on soil physical properties and crop yield in agricultural fields in Niger State, North Central Nigeria. Mechanised land preparation using heavy tractors and disc ploughs is increasingly practiced in Niger State, but repeated passes over the same soil are associated with compaction of the plough layer and subsoil, reducing water infiltration, root development, and crop yields. This problem is particularly significant in the loamy soils of Bida and Minna agricultural zones. This study establishes a controlled field experiment at the Federal University of Technology Minna research farm, applying controlled compaction treatments by varying the number of tractor passes (0, 2, 4, and 8 passes) using a 75-horsepower tractor with different tyre configurations. Soil bulk density, penetration resistance, hydraulic conductivity, and aggregate stability are measured at 0 to 20 and 20 to 40 centimetre depths after compaction treatment application. Maize yield is assessed over two seasons. Findings reveal that increasing tractor passes from 0 to 8 increases soil bulk density from 1.18 to 1.51 grams per cubic centimetre and penetration resistance from 1.2 to 3.4 megapascals. Maize yield declines by 31 percent between 0-pass and 8-pass treatments. The study concludes that soil compaction from tractor operations significantly impairs soil physical quality and crop productivity in Niger State. It recommends reduced tillage practices, controlled traffic farming, and appropriate tyre inflation management.

Keywords: soil compaction, tractor operations, crop yield, Niger State, soil physical properties.