Effect of cultivation on some soil attributes of a long-term pastoral land in the semiarid tropics of Sudan.

Cultivation may have various effects on soil properties and c ould t herefore b e a useful guide of soil quality indices. This study was conducted to determine t he ef fects of m ore than 20 years cultivation of pastoral lands on selected soil chemical (pH, SOM and TN) and physical properties (particle size d istribution (P SD), bulk density (BD), dry aggregate st ability (DAS) and saturation pe rcentage (SP)). Samples ( 0-20, 20-40 and 40-60 cm) were taken from eight profiles of a cul tivated and grazed land. In the top 0-20 cm soil depth, SOM in t he pastoral land (6.3 g kg ) was signif icantly (P £ 0.01) double t hat -1 under cultivated pasture (3.5 g kg ), TN in pastoral land (0. 35 g kg ) was also s ignificantly (P £ 0.01) -1 -1 higher t han that under cu ltivation (0.26 g kg-1), DAS in t he pastoral land (543 g kg ) was significantly -1