基于WEPP模型的砖红壤区坡耕地水平梯田优化设计

Optimum Design of Bench Terrace on Laterite Slope Based on WEPP Model

通过WEPP模型模拟了水平梯田多种设计方案的土壤流失量,结果表明：梯田建设后土壤流失量降低了88.5%~92.1%,说明水平梯田具有很好的水土保持效果。分析了坡度和田坎高对于土壤流失量、土方量和可耕地面积的影响,结果表明：坡度与土壤流失量呈显著正相关,与土方量和可耕地面积呈显著负相关。田坎高与土方量和可耕地面积呈正相关,土壤流失量随田坎高的增加呈先减小后增大的变化趋势。不同坡度最小土壤流失量所对应的田坎高不同,5°,10°,15°,20°,25°分别对应田坎高1.5,2.5,2.0,2.0,2.0 m。WEPP模型可以作为梯田断面参数优化设计的工具。

WEPP model was used to simulate sediment load of the bench terrace under different designs.The results showed that sediment load was decreased by 88.5%～92.1% after terrace construction,indicating bench terrace with obvious effect on soil and water conservation.The effect of slope angle and ridge height on sediment load, earth volume and arable land area was investigated,the results showed that the slope angle was significantly positive to sediment load and the slope angle was significantly negative to earth volume and arable land area. The ridge height was positive to earth volume and arable land area, and sediment load first decreased then increased while the ridge height increased. And ridge height was varied on different slope angle with the minimum sediment load,while 1.5,2.5,2.0,2.0,2.0 m when 5°,10°, 15°, 20°, 25°. The WEPP model could be used as a tool for the optimization of section parameters on terrace.