敦煌沙漠-绿洲过渡带近地表风沙动力环境  

Aeolian Dynamics Environments Near Earth Surface in Desert-Oasis Transitional Zone of Dunhuang Area

作　　者：张克存[1] 牛清河[1] 安志山[1] 张伟民[1] 张号[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所敦煌戈壁荒漠生态与环境研究站沙漠与沙漠化重点实验室,甘肃兰州730000

出　　处：《水土保持通报》2015年第4期8-11,17,共5页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目"沙漠绿洲过渡带近地表风沙动力过程研究"(41371027);中国科学院"西部之光"项目(29Y128841)

摘　　要：[目的]探究沙漠绿洲过渡带起沙风况、输沙势、风沙通量和近地表粒度特征,为阐明沙漠绿洲过渡带风沙动力过程提供理论依据。[方法]利用同步风况、输沙通量和近地表断面粒度资料,分析了沙漠、绿洲及其过渡带输沙势时空分布特征。[结果]由于沙漠和绿洲内部物质组成、空间结构和水热状况不同,沙漠—绿洲过渡风速梯度和起沙风累计作用时间差异显著;受沙漠和绿洲的交互作用,沙漠—绿洲过渡带存在两组主导风向。从近地表粒度特征沿程分布来看,自沙漠至绿洲方向,粗沙含量逐渐降低,粉沙和黏粒含量相对增加。沙漠—绿洲过渡带是绿洲生态系统的重要组成部分,对维持绿洲稳定意义重大。[结论]针对绿洲风沙危害防治,应从局地环流角度出发,充分考虑沙漠—绿洲过渡带的调节和缓冲作用。[Objective] The distribution pattern of sand-driven wind regimes, drift potentials, sand flux and particle size along the desert oasis transitional zone in the Dunhuang oasis adjacent to Mingsha Mountain was investigate in order to provide a theoretical basis for clarifying the process of aeolian sand in desert and oasis regions. [Methods] Based on the data from the synchronous wind velocity, sand flux and the size of sand grains, the characteristics of aeolian sand environments were calculated along the desert oasis transitional zone. [Results] Because of the differences of the material composition, spatial structure and hydrothermal conditions, wind velocity gradient and cumulative time of sand-driven wind existed significant differences. By the interaction of the desert and oasis, two dominant winds existed desert-oasis transitional zone. From the point of near surface granularity characteristics along the distribution, coarse sand content gradually reduced and silt and clay content increased relatively from the desert to the oasis. Desert-oasis transitional zone was the important part of the ecosystem, and had significance in maintaining a stable transition. [Conclusion] For the oasis sand hazard prevention and control, we should give full consideration to the role of regulation and buffering of desert-oasis transitional zone in view of atmospheric circulation.

关 键 词：沙漠—绿洲过渡带 起沙风 输沙势 粒度特征 

分 类 号：P931.3[天文地球—自然地理学] X43[环境科学与工程—灾害防治]