【摘要】 利用安塞试验站1985-1992年的气象观测数据和野外坡度径流小区径流和土壤侵蚀量监测资料,评价了WEPP模型在黄土丘陵沟壑区不同坡度条件下的适用性。结果表明,径流量的模拟值在10°、15°、20°、25°和28°五个坡度条件下,变化幅度不如实测值明显,但模拟值随坡度变化的趋势和实测值相一致;WEPP模型对次降雨、年平均和多年平均土壤侵蚀量模拟结果较好,且无论是模拟值在不同坡度之间的差值、还是模拟值随坡度变化趋势均与实测值接近。I30对WEPP模型模拟次降雨径流量有重要影响,当I30大于0.92mm/min,模型模拟误差较大。WEPP模型对次降雨土壤侵蚀量的模拟与PI30密切相关,当PI30大于129mm2/min时,模型模拟误差较大。∑PI30对WEPP模型模拟年平均径流量和侵蚀量有重要影响,当∑PI30大于150mm2/min时,模拟精度明显下降,且∑PI30对径流模拟影响较对土壤侵蚀模拟影响明显。WEPP模型对次降雨、年平均和多年平均径流量模拟的Nash-Sutcliffe有效性ME分别为0.914、0.912和0.617;对次降雨、年平均和多年平均土壤侵蚀量模拟的Nash-Sutcliffe有效性ME分别为0.858、0.772、和0.827,模拟结果均满足要求。更多还原

【Abstract】 Based on observed meteorological data and measured soil loss data from field runoff plots in 1985-1992 at Ansai Comprehensive Experimental Station,the applicability of WEPP model to different slope gradients on hill-gully region of the Loess Plateau was assessed.The results showed that change range of runoff simulated by WEPP model was not well when the slope gradients were 10,15,20,25,28,respectively.However increasing trends of the runoff simulated values with increase of slope gradients was similar to the runoff of the observed data.The simulated values of event soil loss,annual soil loss,average annual soil loss by WEPP model were quite well when the slope gradients were 10,15,20,25,28,respectively.The differences of simulated values between slope gradients and increasing trend with increase of slope gradient were very close to observed data of the soil loss.I₃₀ had a great effect on runoff simulated values at individual storm;the errors between simulated values and observed data increased when I₃₀ was higher than 0.92mm/min.The soil loss simulated values at individual storm had a close correlation with PI₃₀,and the errors between simulated values and observed values increased when PI₃₀was greater than 129mm²/min.∑PI₃₀ was an important factor to the simulation accuracy of WEPP model,and simulation accuracy decreased when the ∑PI₃₀ was higher than 150mm²/min;meanwhile,the effect of ∑PI₃₀on runoff simulation was greater than that on soil loss.The Nash-Sutcliffe model efficiencies for event runoff simulation,annual runoff simulation and average annual runoff simulation were 0.914,0.912 and 0.617,respectively;and the Nash-Sutcliffe model efficiencies for event soil loss simulation,annual soil loss simulation and average annual soil loss simulation were 0.858,0.772 and 0.827,respectively.The simulated accuracy of runoff and soil loss by WEPP model was satisfied.更多还原