沙漠-黄土过渡带风水复合侵蚀营力特征——以靖边县为例  

Wind and Water Erosive Forces in a Desert-loess Ecotone——A Case Study in Jingbian County,Shaanxi Province

作　　者：杨岩岩[1] 刘连友[1] 曹恒武[2] 

机构地区：[1]北京师范大学减灾与应急管理研究院,北京100875 [2]中国农业科学院农业资源与农业区划研究所,呼伦贝尔草原生态系统国家野外观测研究站,北京100081

出　　处：《干旱区研究》2012年第4期692-698,共7页Arid Zone Research

基　　金：国家自然科学基金"沙生植物构型特征抗风蚀机理研究"(41071331)

摘　　要：以北京师范大学陕西省靖边县榆林风沙科学野外实验站自动气象站2007-2009年的降雨、风速和风向数据为基础,分析沙漠-黄土过渡带风水复合侵蚀营力的特征。结果表明:①研究区年内降雨量≥12 mm的降雨事件主要分布在5-9月,月平均降雨侵蚀力8月最大,为318.24 MJ.mm/(hm2.h.a),年平均降雨侵蚀力为510.08 MJ.mm/(hm2.h.a);②该区西北风占主导地位,东南风次之,累计频率分别为43.8%和16.21%;起沙风主要集中在3-6月,其频率分别为19.34%、12.34%、20.5%、12.39%;③研究区年平均输沙势(DP)、合成输沙势(RDP)分别为228.76 VU、41.73 VU,合成输沙方向(RDD)为141.17°,方向变率指数(RDP/DP)为0.2,起沙风变率较大,属于中等风能环境,沙物质向东南偏南方向输移。In this study, a case study was carried out to research rainfall erosion, wind regime and resultant sand- transporting potential in Jingbian County located in a desert-loess ecotone in Shaanxi Province during the period from 2007 to 2009. The results are as follows： ①The rainfall events with precipitation≥ 12 mm occurred during the period from May to September, the monthly rainfall erosion was the highest in August [318.24 MJ . mm/ （hm2 . h . a） ], and the average annual rainfall erosion was 510.08 MJ. mm/（ hm2 .h . a） ; ② The direction of prevailing wind in the study area was northwest, then southeast, and their cumulative frequencies were 43.8% and 16.21%. The sand-raise wind （6 -9.9 m/s） occurred mainly during the period from March to June, and the oc- curring frequencies in these months were 19.34% , 12.34% , 20.5% and 12.39% respectively; ③ The average sand drift potential （DP） and resultant sand drift potential （RDP） were 228.76 VU and 41.73 VU respectively, the RDP/DP of wind direction was 0.2, and the resultant sand drift direction was 114.17%. All these show that the study area is in a moderate wind energy environment, the variability of monthly wind direction was high, and sand was transported southeastward.

关 键 词：降雨 侵蚀力 起沙风 输沙势 沙漠-黄土过渡带 靖边县 

分 类 号：S157[农业科学—土壤学]