不同扰动方式对沙砾质戈壁地表风蚀量的影响  

Impact of Disturbing Modes on Amount of Wind Erosion of Sandy Gobi

作　　者：殷代英[1] 屈建军[1] 俎瑞平[1] 谭立海[1] 安志山[1] 肖建华[1] 缑倩倩[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/甘肃省风沙灾害防治工程技术研究中心,甘肃兰州730000

出　　处：《中国沙漠》2014年第1期1-8,共8页Journal of Desert Research

基　　金：水利部公益性行业科研专项(201201047;201201048)资助

摘　　要：通过野外风洞实验，测定了不同破坏方式、破坏面积和风速下的沙砾质戈壁风蚀量。结果表明：不同破坏方式引起的风蚀量不同，扰动强度越大造成的风蚀量越多；相同扰动方式下连续破坏造成的风蚀量稍高于间隔破坏。风蚀总量随破坏面积的增大而增加，且服从指数函数。风速为8～10m·s^-1时，扰动的戈壁地表以轻微侵蚀为主；10～12m·s^-1是风蚀量增幅最大阶段；当风速大于12m·s^-1时，以强烈风蚀为主。风沙流中沙物质的主体是细沙和极细沙，在20cm高度范围内，白风沙流下层至上层细沙含量比较稳定，极细沙含量逐渐降低，中沙含量逐渐上升。Field wind tunnel experiments were conducted to measure the quantity of wind erosion under dif- ferent disturbance modes, area of disturbance and wind speeds. Results reveal that the amounts of wind ero- sion under different disturbance modes are different, the more intensity caused by disturbance, the greater the amount of wind erosion. The amount of wind erosion of the disturbance with continuous space is corre- sponding with the disturbance at intervals, and it increases exponentially with increasing the area of disturb- ance and wind speed. When wind speeds are 8--10 m·s^-1, wind erosion of gobi surface is relatively slight. However, as wind speed increases to larger than 12 m·s^-1, strong wind erosion occurs. The amount of wind erosion under 10-- 12 m·s^-1 is between both above. In addition, the change of sand transport rate with height obeys a exponential polynomial function. Sand particles eroded by wind in the experiments are mainly composed of fine and very fine sands in the 0--20 cm near-surface layer. With the increase of height, the proportion of fine sands keeps steady, very fine sands decreases and median sands increases.

关 键 词：沙砾质戈壁 扰动方式 风蚀量 破坏面积 风速 粒度 

分 类 号：P931.3[天文地球—自然地理学]