不同降雨侵蚀力模型在江苏省的比较研究

 研究降雨侵蚀力时空分布特征,准确评估降雨对土壤侵蚀的潜在作用,对土壤流失的预报、水土保持规划等具有积极的意义。利用江苏省2001—2006年260个站点的自记降雨资料和3个降雨侵蚀力模型,对降雨侵蚀力进行不同计算方法的模拟对比,并对江苏省降雨侵蚀力的空间分布进行研究。结果表明:雨量降雨强度模型相对于经典算法的动能降雨强度模型,模拟精度达91.56%,在江苏地区具有一定的适用性;建立的简易雨量模型,数据获取更加便捷,与雨量降雨强度模型相比较,模拟精度达92.81%,在江苏省有一定的推广性;江苏省的降雨侵蚀力空间分布不均匀,具有明显的高值和低值区,R值在年际间变化较大,2003年最大达372.15MJ.mm/(hm2.h.a),2004年最小为168.98 MJ.mm/(hm2.h.a);在江苏省北部和西南地区,特别是连云港等降雨侵蚀力较高城市,应特别加强水土流失的预防和监测。

Comparative study on different rainfall erosivity models in Jiangsu Province

The research on the spatial and temporal distribution of rainfall erosivity and accurate evaluation of the potential effect of rainfall on soil erosion have positive significance on the soil loss forecasting and soil and water conservation planning.In this paper,3 different erosion models are compared on the basis of the analysis of the rainfall records of 260 stations in Jiangsu Province from 2001 to 2006.The results show that the simulated accuracy of the rainfall-intensity model compared with the kinetic energy-intensity model is 91.56%,which is an ideal model and should be used in Jiangsu Province.Moreover,a simple rainfall model is built and its accuracy compared with the rainfall-intensity model is 92.81%.With the convenient method to collect data and simple processing,the sample model is of great applicability and publicity in Jiangsu province.The space distribution of rainfall erosivity in Jiangsu Province is not homogeneous and which formed a distinct high value area and a low value area.The R value changed a lot during the 6 years,which reached a maximum value 372.15MJ·mm/（hm^2·h·a） in 2003 and reached the minimum value 168.98MJ·mm/（hm^2·h·a） in 2004.The high R value regions are located in the northern and southwestern regions of Jiangsu Province especially Lianyungang and other cities,so the prevention and monitoring of soil erosion in those regions should be strengthened.