敦煌月牙泉景区沙丘表面沙物质的粒度特征  

Grain Size Characters of Dune Surface Sediment in the Crescent Spring Scenic Spot,Dunhuang

作　　者：庞营军[1] 屈建军[2] 牛清河[2] 张克存[2] 谢胜波[2] 安志山[2] 

机构地区：[1]中国林业科学研究院荒漠化研究所,北京100091 [2]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：《干旱区研究》2017年第3期701-706,共6页Arid Zone Research

基　　金：国家科技支撑计划项目(2012BAC08B07);国家自然科学基金项目(41271023,41371027)资助

摘　　要：结合风况和蚀积监测数据,系统分析月牙泉南侧线性沙丘、北侧金字塔沙丘表面沙物质粒度特征及其环境指示意义。结果表明:(1)线性沙丘SW坡面以风蚀为主,NE坡面以风积为主,由此导致NE坡面表面沙物质较SW坡面细、分选性好。(2)月牙泉北侧金字塔沙丘SW坡面以风蚀作用为主,沙物质粒径最粗,分选最差。NW坡面也是主要的风蚀面,但由于靠近绿洲防护林,底部以风积为主。E坡面以风积作用为主,沙物质粒径最细、分选最好。(3)从风场、粒度和蚀积变化监测结果来看,对月牙泉危害最大的是南侧线性沙丘NE坡面的积沙。金字塔沙丘SW坡面中部的持续积沙也会对月牙泉构成潜在的威胁。因此,为了更好的保护月牙泉这一自然奇观,应该加强景区周边环境监测与管理。In this study, the grain size characters of pyramid dune at the north and linear dune at the south of Crescent Spring and their environmental significance were analyzed based on the monitoring data of wind regime, wind erosion and deposition. The results are as follows ： （1） The wind erosion occurred mainly on the SW slope of lin- ear dune, and wind deposition occurred mainly on the NE slope, which caused the sand sediment of surface of SW slope to be fine and sorted well; （2） The SW slope of pyramid dune at the north of the Crescent Spring was mainly erosional, and sand sediment was the coarsest and sorted poorly. NW slope was also erosional, while the bottom of slope was depositional due to the proximity of windbreak in oasis ; （3） The data of wind regime, grain size and varia- tion of deposition and erosion showed that sand deposition on the NW slope at the south of the Crescent Spring was the most harmful. The continuous sand accumulation in the middle part of pyramid dune on the SW slope at the north of the Crescent Spring would pose a potential threat to the Crescent Spring. Therefore, it is necessary to strengthen the environmental monitoring and management of scenic spots so as to protect the natural wonders of Crescent Spring,

关 键 词：金字塔沙丘 沙物质 风况 蚀积 粒度 月牙泉 敦煌 

分 类 号：P931.3[天文地球—自然地理学]