新疆策勒不同下垫面大气降尘时空分布特征  

Spatio-temporal Distribution of Atmospheric Dustfall over Different Underlying Surfaces in Qira County,Xinjiang

作　　者：毛东雷[1,2,3] 蔡富艳 雷加强[2,3] 王雪梅[1] 薛杰 来风兵[1] 

机构地区：[1]新疆师范大学地理科学与旅游学院/新疆干旱区湖泊环境与资源重点实验室,新疆乌鲁木齐830054 [2]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [3]新疆策勒荒漠草地生态系统国家野外科学观测研究站,新疆策勒848300 [4]乌鲁木齐职业大学应用工程学院,新疆乌鲁木齐830002

出　　处：《干旱区研究》2017年第6期1222-1229,共8页Arid Zone Research

基　　金：新疆维吾尔自治区高校科研计划项目(XJEDU2016I035);新疆师范大学博士科研启动基金项目(XJNUBS1527);国家自然科学基金项目(41601595,41661002,41661047);国家科技支撑计划项目“塔里木河下游退化生态系统恢复重建技术研发与示范”(2014BAC15B02)资助

摘　　要：认识大气降尘的时空分布规律对研究大气污染、植物生长及当地居民的健康具有重要意义。通过对野外降尘量和平均风速的观测,运用实验分析、统计分析等方法对策勒县域流沙前缘、新开垦地、固定沙地、绿洲内部不同下垫面的降尘进行研究。结果表明:策勒县的降尘主要出现在春夏两季,最大降尘量为2 985.587 g·m-2,位于新开垦流沙地,最小降尘量为1 077.621 g·m-2,位于绿洲内部,且新开垦流沙地降尘量约为绿洲内部的2.77倍;降尘量随着平均风速的增大而减小,并随着静风时间的增长先增大后减少。降尘物质组成成分含量从大到小依次为:极粗粉砂、粗粉砂、极细砂、中粉砂、细粉砂、极细粉砂、细砂、黏土;除了草原站的分选性较差以外,其余几个观测点降尘物的分选性属于中等分选性;流沙地、新开垦未种植流沙地、固定沙地、热瓦克、绿洲内部和大县城降尘物质偏度和峰态都呈负(细)偏、中等峰态,草原站呈负(细)偏、窄峰态,表明植被的覆盖度和高度及农田绿洲化程度会对大气降尘产生重要影响。It is of great significance for researching air pollution,vegetation growth and local people＇s health through understanding the spatial and temporal distribution of atmospheric dustfall. Through observing the dustfall amount and average wind speed in open field,the methods of lab analysis and statistical analysis were used to study dustfall over different underlying surfaces including quicksand frontier,newly reclaimed farmland,fixed sandy land and inner oasis. The results showed that the atmospheric dustfall in Qira County occurred mainly in spring and summer,the maximum dustfall amount was 2 985. 587 g·m-2 and occurred over shifting sandy land in newly reclaimed farmland. The least dustfall amount was 1 077. 621 g·m-2 and occurred in inner oasis. The dustfall amount over shifting sandy land in newly reclaimed farmland was as high as 2. 77 times of that in inner oasis. The dustfall amount was decreased with the increase of average wind speed,and it was increased at first and then decreased with the time increase of calm wind. The composition of dustfall materials was that the content of very coarse silt was higher than that of coarse silt,very fine sand,moderate silt,fine silt,very fine silt,fine sand and clay. The sorting of dustfall was moderate except that at the Grassland Station. Skewness and kurtosis of dustfall materials from the sites of quicksand frontier,newly reclaimed land,fixed sandy land and Rawak Station were the negative skewness and moderate platykurtic,and those from Grassland Station were the negative skewness and narrow kurtosis,separately.These revealed that the vegetation coverage and height as well as the degree of oasisization played an important role in atmospheric dustfall.

关 键 词：大气环境 降尘 时空分布 风速 粒度 策勒 

分 类 号：X513[环境科学与工程—环境工程]