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The different height mass concentrations of dust aerosol data from the atmosphere environment observation station (Ta- zhong Station) was continuously observed by instruments of Grimm 1.108, Thermo RP 1400a and TSP from January of 2009 to February of 2010 in the Taklimakan Desert hinterland. Results show that: (1) The mass concentration value of 80 m PMl0 was higher, but PM2.5 and PM1.0 concentrations at 80 m was obviously lower than 4 m PMl0, and the value of 80 m PM1.0 mass concentration was the lowest. (2) The PM mass concentrations gradually decreased from night to sunrise, with the lowest concentration at 08:00, with the mass concentration gradually increased, up to the highest concentration around 18:00, and then decreased again. It was exactly the same with the changes of wind speed. (3) The high monthly average mass concentration of TSP mainly appeared from March to September, and the highest concentration was in April and May, subsequently gradually decreased. Also, March-September was a period with high value area of PM monthly average mass concentration, with the highest monthly average mass concentration of 846.0 p.g/m3 for 4 m PM~0 appeared in May. The concentration of PM10 was much higher than those of PM2.5 and PM1.0 at 80 m. There is a small difference between the concentration of PM2.5 and PM~ 0. Dust weather was the main factor which influenced the concentration content of the different diameter dust aerosol, and the more dust weather days, the higher content of coarse particle, conversely, fine particle was more. (4) The mass concentration of different diameter aerosols had the following sequence during dust weather: clear day 〈 blowing dust 〈 floating and blowing dust 〈 sandstorm. In different dust weather, the value of PM~o/TSP in fine weather was higher than that in floating weather, and much higher than those in blowing dust and sandstorm weather. (5) During the dust weather process, dust aerosol concentration gradually decreased with particle size decreasing. The dust aerosol mass concentration at different heights and diameter would have a peak value area every 3-4 days according to the strengthening process of dust weather. 相似文献
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杨逸畴先生是我国著名的地貌学家, 他将毕生的精力贡献给了祖国的地理科学事业。1959-1998 年他前后20 余次到青藏高原考察, 其中二次在喜玛拉雅山库拉岗日峰和南迦巴瓦峰参加登山科考, 八次进入雅鲁藏布大峡谷考察。他五次深入新疆塔克拉玛干大沙漠腹地考察。2001 年后, 他还开展了对台湾澎湖、兰屿、绿岛的历史环境考察。他曾四次到日本考察并开展学术交流, 2003 参加了北极考察。他在多年实地考察基础上, 以丰富的资料和测量数据, 参与论证和确认我国雅鲁藏布大峡谷作为世界第一大峡谷的科学地位, 为中国地理学赢得了世界声誉。 相似文献
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塔克拉玛干沙漠公路沿线风沙活动的时空分布 总被引:13,自引:3,他引:13
利用塔克拉玛干沙漠公路沿线的肖塘、满参和塔中3 个定位观测站1 个自然年的监测资料,对以起沙风和输沙强度为表征的风沙活动进行了分析。选取气象站标准高度10 min风速中大于临界起沙风速(≥6.0 m/s)的风,按16方位分别统计不同级别风的次数及其方位,计算输沙量。结果表明,风沙危害的主风向为偏东风,频率范围48%~76%。风沙活动集中在4~9月;从沙漠边缘向腹地风沙活动加强。向沙漠腹地深入,应加大公路风沙危害防护力度。 相似文献
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沙漠腹地春夏季近地层大气湍流特征观测分析 总被引:2,自引:6,他引:2
利用塔克拉玛干沙漠腹地近地层10 m高度处快速响应探测系统的湍流资料,分析了摩擦速度和特征温度的变化,并且对不同稳定层结条件下无因次速度分量方差和无因次温度方差的普适函数进行详细拟合。研究表明,摩擦速度和特征温度有明显的日变化特征,且摩擦速度的最大值出现在z/L=-0.2处;无因次速度方差在不稳定和稳定层结条件下均符合相似理论的次幂律,但如果考虑到相关性,最佳幂指数可有不同;近中性时则接近常数,并给出了具体数值。无因次温度方差则在夏季不稳定层结条件时符合-1/3次幂律。 相似文献
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塔克拉玛干地区近四十年来的干湿变化 总被引:3,自引:1,他引:3
本文利用塔克玛干,周围山区、及相邻地区的48个气象站近40年的降水资料,分析塔克拉玛干地区年与四季干湿变化的阶段与周期,与与周围山区及相邻地区进行相关性分析。 相似文献
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塔克拉玛干地区干湿波动与全球温度变化关系探讨 总被引:9,自引:1,他引:9
塔克拉玛干地区随着青藏高原隆起形成大沙漠以来,一直处于干旱环境,但存在着相对干湿波动,与全球温度变化呈现的冷干-暖湿特征相一致。认为沙漠化事件主要是发生在气候变冷、变干背景下,加上人类活动共同影响所致。历史上古遗址的废弃大多发生在冷干期。 相似文献
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塔克拉玛干沙漠公路风沙危害与防治 总被引:23,自引:0,他引:23
塔克拉玛干沙漠公路447 km路段穿越新月形沙丘与沙丘链、复合横向沙垄以及高大复合纵向沙垄区,风沙危害极为严重,被誉为“世界公路建筑的奇迹”。为解决沙漠公路风沙防护体系构建的一系列科学与技术问题,沙漠学界随之开展了风沙运动规律,风沙危害的成因、强度、时空分异及其机械、化学、生物防治的理论与应用研究。本文对风沙危害及其防治研究的主要内容及研究进展进行了全面总结,认为塔克拉玛干沙漠公路风沙危害与防治的理论研究成果与实践应用水平取得突破性进展。 相似文献