塔里木河下游荒漠河岸林近地表沙尘通量及粒度特征  

Flux and Particle Size Characteristics of Landscape Sediments in a Desert Riparian Forest Along Lower Reaches of Tarim River

作　　者：王慧娟[1,2] 塔依尔江·艾山 玉米提·哈力克[1,2] 王娜[1,2] 买尔哈巴·吾买尔[1,2] Wang Huijuan;Tayierjiang Aishan;Yumiti Halike;Wang Na;Maierhaba Wumaier(College of Ecology and Environment,Xinjiang University,Urumqi,Xinjiang 830046,China;Ministry of Education Key Laboratory of Oasis Ecology,Urumqi,Xinjiang 830046,China)

机构地区：[1]新疆大学生态与环境学院,新疆乌鲁木齐830046 [2]绿洲生态教育部重点实验室,新疆乌鲁木齐830046

出　　处：《水土保持通报》2023年第2期16-22,33,共8页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目“塔里木河流域胡杨干材腐朽的定量诊断及驱动机制探析”(32160367);“林窗干扰对胡杨荒漠河岸林更新与演替的影响”(31860134)。

摘　　要：[目的]分析主导风向下塔里木河下游阿拉干断面天然胡杨河岸林迎风面和背风面的沙尘输沙量及粒度特征,为该区天然河岸林防风固沙提供理论依据。[方法]利用BSNE梯度集沙仪采集两个迎风面样地(Y_(1),Y_(2))和两个背风面样地(B_(1),B_(2))近地表10,30,50,100和150 cm这5个高度的沉积物,再由Microtrac S3500激光衍射粒度分析仪测定沙样粒度特征。[结果]①4个样地沙尘水平通量皆遵循幂函数或指数函数分布,总输沙量呈现:Y_(1)>Y_(2)>B_(1)>B_(2),各样地随着离地表高度的增加输沙量呈减少趋势。②背风面相较于迎风面输沙量降幅在35%~80%之间,说明塔里木河下游天然胡杨河岸林具有较显著的防风固沙效益。③各高度沙粒平均粒径为80~93μm,以极细沙为主,粒径频率曲线呈单峰分布,沙尘组成简单,以局地沙源为主。[结论]研究区天然胡杨河岸林背风面输沙量低于迎风面、平均粒径小于迎风面、分选性优于迎风面、峰态窄于迎风面、偏度稍小于迎风面。因此胡杨河岸林防风固沙效益较显著,可作为减少研究区风沙天气危害的有效措施。[Objective]The characteristics of sand and dust transport amount and particle size on the windward and leeward sides of a natural Populus euphratica riparian forest at the Arghan section of the lower reaches of the Tarim River under the prevailing wind direction were studied in order to provide a theoretical basis for its windbreak and sand fixation capacity.[Methods]Sediments were collected from two windward sites(Y_(1)and Y_(2))and two leeward sites(B 1 and B 2)of the forest at five heights of 10,30,50,100,and 150 cm near the surface using a BSNE sand collector.The particle size characteristics of the sand samples were then measured using a Microtrac S3500 laser diffraction particle size analyzer.[Results]①The horizontal flux of sand and dust in the four sample plots followed either a power function or exponential function distribution,and total sediment transport followed the order of Y_(1)>Y_(2)>B_(1)>B_(2).The sediment transport for each sample plot decreased with increasing height from the soil surface.②The reduction of sediment on the leeward side compared with the windward side ranged from 35%to 80%less than on the windward side,indicating that the natural P.euphratica riparian forest in the lower reaches of the Tarim River has obvious windbreak and sand fixation benefits.③The average particle size of sand grains at all heights was 80~93μm,mainly composed of extremely fine sand.The particle size frequency curve showed a single peak distribution,and the sand dust composition was simple,mainly composed of local sand sources.[Conclusion]The sediment transport on the leeward side of the natural P.euphratica riparian forest in the study area was lower than that of the windward side.Average particle size was smaller and sorting performance was better on the leeward side than on windward side.The average particle size smaller than that of the windward side,the sorting was better than that of the windward side,the kurtosis was narrower than that of windward side,and skewness is slightly smaller than that o

关 键 词：输沙通量 粒度特征 防风效益 荒漠河岸林 塔里木河 

分 类 号：P931.3[天文地球—自然地理学]