The effects of different management practices on the physical properties of a sandy loam soil in Southern Nigeria were studied for two cropping seasons. The bulk densities of the top 0–10-cm soil depths were significantly reduced in plots under 13 years of Panicum maximum and Centrosema pubescens covers. Pores of equivalent cylindrical diameter > 0.05 mm were increased significantly under the two covers. Up to 33% of the saturation water content was released between tensions of 0 and 0.06 bar in the sandy loam soil of all the treatment plots. Furthermore an average of 24% of this water was released between tensions of 0.06 and 0.33 bar. Infiltration rates, measured at the end of the growing season, ranged from 240 mm h−1 under the bare fallow treatment to 1326 mm h−1 under the Centrosema cover. There was no significant difference between the tilled and no-tillage plots. Saturated hydraulic conductivities were significantly higher under the Panicum and Centrosema covers. The effect of tillage on conductivity was not appreciable. The highest weekly 5-cm depth, 1.30 p.m. soil temperature (32°C) was obtained under the bare fallow treatment and the lowest (23.5°) under the Panicum cover. Tillage had no significant effect on the soil temperature. Thirteen years of continuous Centrosema and Panicum covers had a significant effect on the physical properties of the tropical sandy loam soil. Tillage effects were not significant after 2 years of cropping.
Soil and Tillage Research 07/1988; 12(1):81-90. DOI:10.1016/0167-1987(88)90057-8