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| Analysis of the runoff cost for sediment control by slope soil and water conservation measures |
| (1. College of Resources and Environment, Northwest A&F University, 712100,Yangling, Shaanxi; 2. Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, 712100,Yangling, Shaanxi; China） |
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Abstract Runoff cost for sediment control, shown as ratio of detained runoff and sediment (Rrs) of different soil and water conservation measures is an important integrated indicator to intuitive evaluate the impact of different soil and water conservation measures on runoff and sediment synchronously. Based on the experimental data measured in runoff plots in Xifeng and Tianshui stations for many years, the runoff cost for sediment control under different tillage measures and biological measures were analyzed. The results showed that the Rrs of different tillage and biological measures were greatly impacted by I30 and slope, and the RRS was negatively correlated to the two factors. As to the tillage measures and biological measures, the relationship between Rrs and slope appeared as a exponential function as I30 was more than 0.29mm/min and 0.48mm/min respectively. The orders of runoff cost for sediment control for different tillage measures were: level ditch tillage>shallow plowing>deep plowing, and Rrs of level ditch tillage is higher than that of deep plowing by 33.8%. As to biological measures the orders of runoff cost for sediment control were: intercropping between low-stem and high-stem crops (corn/soybean)>monoculture of low-stem crops (lentils)>rotation between middle-stem crops (winter wheat/buckwheat).
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Received: 24 April 2012
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