安康市降水对土壤侵蚀的影响调查研究.docVIP

安康市降水对土壤侵蚀的影响调查研究 　　摘要 利用日降雨数据估算降雨侵蚀力，以此来反映降雨引起土壤侵蚀的潜在能力。通过分析安康市及周边4个气象站点1960―2009年的逐日降雨数据，基于降雨侵蚀力的简易算法，计算分析了降雨侵蚀力的空间分布特征和时间变化。结果表明，安康市降雨侵蚀力在空间分布上呈现西高东低的特征，分布特征与降水量的空间分布特征基本一致；降雨侵蚀力在年际变化上与降水量呈现一致的特点，年际变化特征与降雨量和降雨强度相关性较大，降雨侵蚀力的趋势系数结果表明降水对土壤侵蚀的能力基本呈现出增加的趋势；降雨侵蚀力在年内的变化特点是主要集中在4―10月，占全年的97.2%，最大月份为7月，占全年的23.8%。研究结果为安康市水土流失防治和水土保持区划工作提供了参考依据。 　　关键词 降雨侵蚀力；降水量；时空变化；趋势分析；陕西安康 　　中图分类号 S157；P426.6 文献标识码 A 文章编号 1007-5739（2016）17-0165-03 　　Abstract Estimation of rainfall erosion was conducted by daily rainfall data，in order to reflect the potential capacity of soil erosion by rainfall. Through the analysis of 4 meteorological stations daily rainfall data during 1960-2009 in Ankang City and the surrounding areas，the simple algorithm based on rainfall erosivity，the spatial distribution and temporal variation of rainfall erosivity were calculated and analyzed. The results showed that，the rainfall erosivity of Ankang City is high in west and low in east in the spatial distribution，the spatial distribution is consistent with precipitation；the rainfall erosivity characteristics is consistent with precipitation in the interannual variation，the interannual variation features is correlated with precipitation and rainfall intensity，the results of erosion force showed that the precipitation on the capacity of soil erosion show an increasing trend；the changes of rainfall erosivity in the year is mainly concentrated in April to October，accounting for 97.2% of the year，and the maximum appear in July，accounting for 23.8% of the year. The results provided reference basis for prevention and control of soil and water conservation and regionalization of soil erosion in Ankang City. 　　Key words rainfall erosivity；precipitation；temporal and spatial variation；trend analysis；Ankang Shaanxi 　　全球气候变化尤其是降水的变化对土壤侵蚀带来极其复杂的影响。联合国政府间气候变化委员会第四次评估报告认为，目前多数地区强降雨事件出现频次的增加很可能加重土壤侵蚀率[1]。引起土壤侵蚀的主要动力是降水，由雨滴溅蚀、分离土壤颗粒以及降雨形成的径流产生的搬运作用是引起土壤侵蚀的主要动力。降雨引起土壤侵蚀的这种潜在能力可以用降雨侵蚀力来表征[2]。客观准确地评估计算我国的降雨侵蚀力，分析其时间和空间的变化规律，