亚洲沙尘源区砂质土壤同位素特征分析  

Isotopic Characteristics of Asian Dust Source Regions of Deserts and Sandy Lands

作　　者：覃伟民[1] 袁中新[1] 刘丛强[2] 

机构地区：[1]中山大学环境工程研究所,台湾高雄80424 [2]中国科学院地球化学研究所,贵州贵阳550002

出　　处：《过程工程学报》2009年第S2期101-106,共6页The Chinese Journal of Process Engineering

摘　　要：为探讨亚洲沙源地可能经风卷扬后,透过大气长程传输的PM2.5-10沙尘微粒同位素特征,于2004年3~4月及2005年9月期间在内蒙古自治区的腾格里沙漠、毛乌素沙漠、浑善达克沙地、科尔沁沙地采集到17个代表性土壤样本,并依地理位置将腾格里沙漠、毛乌素沙漠划分为西区;而将浑善达克沙地、科尔沁沙地划分为东区,再藉由风力再悬浮法将沙尘重新悬浮于空气中,并以双粒径分道采样器进行悬浮微粒采样.采集主要影响下风区域的PM2.5-10沙尘样本,以NuPlasma型液离子源质谱仪进行87Sr/86Sr比值特征分析,初步建立沙源地中沙尘微粒PM2.5-10的源谱特性,并配合沙源地化学指纹特征与Sr同位素的影响变化,进行相关性分析探讨.研究结果表明,东、西两区沙尘微粒PM2.5-10的Sr与Ca含量具有良好的正相关性.此外,东、西区两地沙漠地的Sr同位素特征具有显着差异,其中西区毛乌素沙漠的沙尘样本变异量最大;而东区浑善达克沙地及科尔沁沙地的沙尘样本具有相似的Sr同位素表土特征,两地的变异量皆最小,就地理位置而言,推测两处沙地的形成可能与邻近的山脉有关.The isotopic characteristics of PM2.5-10 from Asian dust source regions by long-range transportation were investigated.During the spring of 2004,17 soil samples were collected at various land surfaces in Inner Mongolia,Tengger Desert,Mu Us Desert,Hun Shan Da Ke Sandy Land,and Horqin Sandy Land.According to the geographic locations,Tengger Desert and Mu Us Desert were classified as west sites,Hun Shan Da Ke Sandy Land and Horqin Sandy Land as east sites.Soil samples were resuspended inside a resuspension chamber and then collected by a dichotomous sampler.This study focused on PM2.5-10 particles that mainly influence the downwind regions.A multiple-collector inductively coupled plasma mass spectrometer was used to determine the isotopic characteristics of 87Sr/86Sr ratio.The chemical compositions of dust source regions with its Sr isotopic composition were compared to investigate the variation of Sr isotopic characteristics.Experimental results showed that a positive correlation was observed between Sr and Ca contents of PM2.5-10.Additionally,the Sr isotopic characteristics between the east and the west sites were significantly different.However,there was no significant difference between Hun Shan Da Ke Sandy Land and Horqin Sandy Land.The above results indicated that the soils of the two sandy lands come from the same nearby mountains.

关 键 词：亚洲沙尘源区 PM2.5-10悬浮微粒 SR同位素 沙尘源谱 

分 类 号：X513[环境科学与工程—环境工程]