Soil Erosion under Simulated Rainfall in Loess Lands with Emphasis on Land-Use, Slope and Aspect

The runoff generation and soil erosion in the Kechik Watershed, Golestan Province, was assessed, using a designed and constructed portable rainfall simulator. Treatments were applied on different land-uses, slopes and aspects as the most influential factors. Results showed that land-use significantly affected runoff generation (13.35 l, 6.9 l, and 4.12 l, respectively for agriculture, forest and rangeland uses), however slope (7.7 l for Class I; 9.23 l for Class II) and aspect (8.52 l for the northern aspects; 8.32 l for the southern aspects) did not have significant influence. All factors, significantly altered sediment concentration (Agriculture 9.6 g l-1, forest 8.24 g l-1, and rangeland 5.26 g l-1; slope class I 6.6 g l-1 and slope class II 8.7 g l-1; northern aspect 8.7 g l-1, and southern aspect 6.9 g l-1). Agricultural fields generated the highest runoff and sediment under simulated rainfalls. Rangeland and forest did not have significant runoff generation and sediment concentration. Results showed that land-use management, especially in terms of agriculture, could not only hamper current erosion, but reduced further advancement of this encroaching phenomenon.

Soil Erosion under Simulated Rainfall in Loess Lands with Emphasis on Land-Use, Slope and Aspect Keywords:

Golestan Province , Land conversion , Rainfall simulator , Runoff generation , Soil loss