摘要
降雨侵蚀力可用于表征降雨对土壤侵蚀的潜在能力,研究其时空变化特征对流域土壤侵蚀风险评估、水土流失防控等工作具有重要意义。利用赣江流域12个气象站1958—2014年逐日降雨资料计算降雨侵蚀力,采用TFPW-MK法、小波分析和Kriging插值等方法分析了流域降雨侵蚀力时空变化规律。结果表明:赣江流域多年平均降雨侵蚀力值空间分布范围为6059.9~8724.7(MJ·mm)/(hm^2·h),空间上自西南向东北呈现递增趋势;大部分站年降雨侵蚀力以上升为主,1958—2014年流域年降雨侵蚀力上升了588.639(MJ·mm)/(hm^2·h),上游区变化较小,中下游上升趋势较明显,其中7—9月变化显著。此外,流域年降雨侵蚀力的变化主周期为4.1 a,且存在2.0~5.2 a的振荡周期。研究表明赣江流域因降雨侵蚀力增加而引发水土流失的风险在加剧,对于下游地区表现尤为突出,结论可为赣江流域水土保持、农业开发等提供决策依据。
A rainfall erosivity factor can be used to measure the rain potential ability to cause soil erosion.It is important to analyze on the characteristics of rainfall erosivity,the assessment of soil erosion risk and the prevention and control of soil erosion.In this paper,the monthly rainfall erosivity model was introduced to calculate the rainfall erosivity.Ganjiang River Basin(GRB)was taken as the study case.The daily rainfall data of 12 meteorological stations from 1958 to 2014 were used in the model.The methods including TFPW-MK,wavelet analysis and Kriging interpolation were used to analyze the spatiotemporal variation of rainfall erosivity.The results show that the range of annual rainfall erosivity in GRB is 6059.9~8724.7(MJ·mm)/(hm^2·h)during the period 1958—2014,the average annual rainfall erosivity increases from southwest to northeast in general,annual rainfall erosivity of most stations displays the increasing trends from 1958 to 2014;the annual areal rainfall erosivity of GRB shows the significant increasing trend with yearly average slope of 12.250(MJ·mm)/(hm^2·h),annual areal rainfall erosivity of upper basin shows the slightly decreasing trend,while it displays the increasing trend in the middle and lower basins,especially for the period from July to September;In addition,the rainfall erosivity frequence from 1958 to 2014 had the main period of 4.1 years,with an oscillation periods of 2.0~5.8 years,indicating that the risk of soil erosion in GRB is increasing,especially in the lower basin.These results can provide the important reference for soil and water conservation planning,agricultural developing in this basin.
作者
温天福
张范平
胡建民
刘章君
WEN Tianfu;ZHANG Fanping;HU Jianmin;LIU Zhangjun(Jiangxi Provincial Institute of Water Sciences,Nanchang 330029,China)
出处
《水土保持研究》
CSCD
北大核心
2020年第1期7-14,20,共9页
Research of Soil and Water Conservation
基金
江西水利科技支撑项目(201821ZDKT07,201821ZDKT15,KT201508,KT201501)
江西省科技计划项目(2015ZBBF60006)
