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Ionic Chemistry in Snowpits from Yamzhog Yumco Basion
羊卓雍流域雪坑中化学离子记录研究

ZHENG Wei,YAO Tan-dong,XU Bai-qing,ZHAO Hua-biao,
郑伟
,姚檀栋,徐柏青,赵华标

环境科学 , 2008,
Abstract: During August and September, 2006, a total of 50 samples had been collected from three different snowpits at the Yamzhog Yumco Basion in the south of the Tibetan Plateau. All samples were analyzed for major cations (Na+, NH4+, K+, Ca2+ and Mg2+), anions (Cl-, SO4(2-) and NO3-) and stable oxygen isotope ratio. The results of analyses show that the three snowpits represent accordant chemical characteristics, with NO3- (16.1-187.2 microg x L(-1), averaging at 93.7 microg x L(-1)) and Ca2+ (19.0-236.7 microg x L(-1), averaging at 81.0 microg x L(-1)) being the highest concentration of anions and cations respectively. Compared with data from other representative sites, major ion concentrations in the Yamzhog Yumco Basion accord with those in the south of the plateau, but they differ much from those in the north of th eplateau. Remarkable variabilities of major ion concentrations from monsoon period to non-monsoon period are demonstrated. Ion concentrations of NO3-, NH4+ increase 30%-40% in monsoon period due to the influences of vegetation, live-stock, anthropogenic activity and thunderstorm, whilst the concentrations of crustal source ions, such as Ca2+, Mg2+ reduce 80% due to decrease of dust and strong wind from the north of the plateau and crustal aerosols being washed out of the atmosphere by heavy precipitation during the monsoon period. Variation of ion concentrations are also impacted by elevation and post-deposition process, with Ca2+, Mg2+ increasing with a decrease in elevation and SO4(2-), NO3- decrease with an increase in elevation and the influence of post-deposition.
Mineral and Elemental Characteristics of Microparticles with Different Size Fraction in Snowpits from Zadang Glacier
扎当冰川雪坑中不同粒径微粒元素和矿物组成特征

YU Guang-ming,XU Jian-zhong,KANG Shi-chang,HUANG Jie,REN Jia-wen,
余光明
,徐建中,康世昌,黄杰,任贾文

环境科学 , 2011,
Abstract: In order to study the mineral and elemental composition of insoluble microparticles (IP) in snow/ice, two snowpits were collected from the Zadang Glacier in Mt. Nyainqentanglha (30.47 degrees N, 90. 65 degrees E, 5 800 m a. s. l) in May and July, 2009, and IP samples were investigated. The measurements of mineral composition with different size fractions (d > 10 microm and 0.22 microm < d < 10 microm) were carried out using Particle-induced X-ray emission (PIXE) and X-ray diffraction analysis (XRD). The main mineral components of both coarse and fine IP are quartz, mica and calcite, accounting for 71.5% and 76.5%, respectively. The crustal elements concentrations (e.g. Si, Al, Fe, K, Mg and Ca) are 97% and 85.1% of total coarse/fine IP, while S, Cl and P take fairly proportion in fine microparticles (d < 10 microm). Seasonal variability of mineral composition in coarse microparticles (d >10 microm) is not obviously; However it's significantly in fine IP. Enrichment factors (EF) analysis reveals that several elements (e.g. Sc, P, Cr, S and Cl) in fine IP during monsoon season have high values which indicate these elements may be influenced by anthropogenic activities. Backward air mass trajectory analysis suggests that air masses in this region mainly originate from the South Asia areas during monsoon season, and air masses mainly come from arid/semi-arid region in the South and West Asia during non-monsoon season. Therefore, anthropogenic pollutants from the South Asia may be transported by the summer Indian monsoon to the Zadang glacier area. The coarse IP may derive from the local or remote mineral dust, and chemical compositions of fine IP interfere with anthropogenic pollutants.
Microparticle Variations in Snowpits from Mt.Geladaindong in the Source Region of Yangtze River and Its Environmental Significance
长江源区各拉丹冬峰雪冰中微粒季节变化及其环境意义

ZHANG Yu-lan,KANG Shi-chang,ZHANG Qiang-gong,CONG Zhi-yuan,ZHANG Yong-jun,
张玉兰
,康世昌,张强弓,丛志远,张拥军

环境科学 , 2008,
Abstract: To study the variations of microparticles and their origins, microparticles concentrations, stable oxygen isotope (delta18 O) and major ion concentrations were analyzed in snow samples collected from Mt. Geladaindong in the source region of Yangtze River. The correlation coefficents of different size microparticles in three snowpits are above 0.9 (significant at the 99% level), respectively. Microparticle concentrations have distinct seasonal variations, about 2-4 times higher in non-monsoon season than those in monsoon season, and are consistent with variations of delta18 O, Ca2+, Mg2+ and SO4(2-). Microparticle fluxes in non-monsoon season in three snowpits are 73.6%, 92.3% & 97% of total annual fluxes, respectively. Air mass backward trajectories over Mt. Geladaindong region were analyzed using the HYSPLIT_4 model, and microparticles in Mt. Geladaindong snow were mostly influenced by dust aerosols from the northwestern Tibetan Plateau, South Asia. Coarse particles may come from the local rocks near glaciers. Research of seasonality of microparticle in snow could provide the information on modern environment processes, and is the base of further interpretation of ice core records.
典型海洋型冰川区消融期雪坑层位演变及离子沉积后过程初探  [PDF]
张宁宁,何元庆,庞洪喜,和献中
冰川冻土 , 2010,
Abstract: 2006年4-7月,在玉龙雪山白水1号冰川消融区(P1)和积累区(P2)分别开挖雪坑连进行续观测,分析了海洋型冰川在消融期雪坑内各层位的物理变化以及各离子的沉积后过程.结果表明海洋型冰川区雪坑的消融速率远大于大陆型冰川;随着消融的进行,雪坑中各种粒雪成分逐渐向粗粒雪转化,同时冰片数量增多以及含水层加厚,并且向雪坑底部移动.雪坑消融可以分为雪坑内部的细粒雪、中粒雪向粗粒雪转变,雪坑厚度变化不大以及雪坑厚度的快速变薄两个过程,P2处两消融过程转变时间比P1处大约推迟两个月.根据各种离子在P1处雪坑剖面的浓度变化,白水1号冰川积累区的淋溶序列为K+>SO42->NO3->Cl->Ca2+>Mg2+>Na+.由于海洋型冰川的消融期也是它的积累期,该序列中各离子的顺序不仅反映了融水淋溶作用的影响,同时反映了物质输入对雪坑内离子浓度变化的影响.
天山奎屯河哈希勒根51号冰川雪坑化学特征及环境意义  [PDF]
董志文,李忠勤,张明军,王文彬,王飞腾
地理科学 , 2010,
Abstract: 2004~2007年在天山奎屯河哈希勒根51号冰川采集3个雪坑样品。运用相关分析、海盐示踪法等方法,对化学要素的季节变化特征及主要阴阳离子来源进行分析研究。结果表明,雪坑中不溶粉尘和主要化学离子具有明显的季节变化特征;春季期间降雪中粉尘浓度明显高于其他季节。主要离子的浓度在沙尘季节也明显高于非沙尘季节。雪坑中Ca2+是主要阳离子,SO42-是主要阴离子。除NO3-外,雪坑中其他离子浓度之间均存在较好正相关。表明冰川区主要受中亚地区沙尘活动影响;同时雪坑中的离子(尤其是Na+)除陆源矿物粉尘之外,一定程度源于海洋源。
乌鲁木齐河源1号冰川雪坑δ18O剖面特征与气候的关系  [PDF]
?李亚举,张明军,李忠勤,王圣杰,王飞腾
干旱区研究 , 2011,
Abstract: 004年10月至2005年9月,在天山乌鲁木齐河源1号冰川积累区采集了16组雪坑样品。利用雪坑中δ18O资料,分析干季和湿季冰川雪坑δ18O剖面特征与气候的关系。结果表明δ18O变化主要集中在雪坑上部,在距底部附加冰130cm以下变化不大,且维持在较高值。其中,干季雪层剖面上部基本反映了积累期温度的变化,湿季不同雪层之间的同位素差异变小,峰值削弱,反映了同位素分馏在干湿季的不同作用,体现了同位素后沉积作用的富集与均质化效应的季节差异。
天山东部冰川雪坑离子浓度特征的对比研究  [PDF]
李向应,刘时银,韩添丁,李忠勤,卢爱刚
地球科学进展 , 2008, DOI: 10.11867/j.issn.1001-8166.2008.12.1268
Abstract: 对2004年获取的天山奎屯河哈希勒根51号冰川1个雪坑和哈密庙尔沟平顶冰川4个雪坑的离子浓度特征进行了研究,结果表明Ca2+、NO-3和SO42-是哈密庙尔沟平顶冰川雪坑雪层和积累区雪坑底部冰中的主要离子(尤其是Ca2+),其雪层中的主要阳离子关系可在底部冰中得以较好的反映,但雪层中各离子浓度与海拔的相关性不明显,可能与海拔的跨度较小和挖取的雪坑较疏有关;雪坑底部冰中的离子浓度与海拔间明显的相关性说明淋融作用随着海拔升高、气温降低而逐渐减弱。SO42-和Ca2+是奎屯河哈希勒根51号冰川雪坑中的主要离子(尤其是SO42-),其雪坑离子化学特征与哈密庙尔沟平顶冰川差别较大,可能与哈密庙尔沟平顶冰川处于塔克拉玛干沙漠、古尔班通古特沙漠和鄯善沙漠的下风向相关,还可能与雪层内淋融作用的强弱和沉积通量的高程效应有关。哈密庙尔沟平顶冰川积累区雪坑中NH4+、NO3-和K+的Cs/Ci较Ca2+、Mg2+和Na+要大,奎屯河哈希勒根51号冰川Na+和NH4+的“雪冰比”较Cl-、SO42-、Mg2+和Ca2+要大,说明这两条冰川雪坑中的Ca2+和Mg2+信号较其它离子可能更易于在冰芯记录中保存下来,为冰芯研究和古气候记录的恢复提供了保障。
中亚天山托木尔峰地区青冰滩72号冰川雪坑化学特征及其环境指示意义  [PDF]
张晓宇,李忠勤,王飞腾,王圣杰
地理科学 , 2012,
Abstract: 基于2008年7月天山托木尔峰地区青冰滩72号冰川雪坑实测资料,探讨其冰川雪坑离子化学特征及环境指示意义。研究发现,Ca2+、Mg2+是青冰滩72号冰川雪坑中主要阳离子;雪坑中阳离子浓度顺序为Ca2+>Mg2+>Na+>K+>NH4+,其中,Mg2+、K+和Ca2+主要反映长距离沙尘源物质传输情况;Cl-和Na+则一半以上来源于海盐;青冰滩72号冰川NO3-浓度高于天山地区含量平均值。
沉积后过程对冰川渗浸带雪坑化学剖面的影响  [PDF]
侯书贵
冰川冻土 , 2001,
Abstract: 通过乌鲁木齐河源1号冰川西支典型渗浸带内同一位置先后获取的一个3.0m和一个2.3m雪坑化学剖面的比较,发现沉积后过程不仅能够改变雪层的原始峰谷位置,且能导致不同种类化学记录间的位相差异.在利用高消融地区冰芯记录进行古气候和古环境恢复时,有必要排除沉积后作用对雪层原始化学记录的干扰作用.
东南极冰盖内陆深处几个雪坑离子浓度的初步研究  [PDF]
任贾文,孙俊英,秦大河,效存德
冰川冻土 , 2004,
Abstract: 对南极中山站-DomeA断面距海岸800~1100km(海拔2850~3760m)的内陆深处3个雪坑进行了雪层剖面观测和雪样化学分析.氧同位素、可见层位特征与主要阴、阳离子浓度的剖面对比分析表明,同位素季节变化信号不明显,而太阳辐射冰壳与某些离子(如Na+、Cl-等)浓度变化有较好的对应.研究区域主要的几种离子如Na+、Cl-和SO42-等与东南极内陆其它区域雪坑中的相似,但NO-3和NH+4有较大差异.在高原中心区域,NO3-沉积后很大部分又逸散返回大气,因而雪层中平均浓度很低但表面处的浓度却异常地高.在海拔2850m处,各种离子的浓度随深度增加而增加,在海拔3750m处则为相反趋势,在海拔3380m处趋势不明显.如果离子沉降速率保持不变,这种特征意味着近20a来降雪积累速率在高原中心区域为减少趋势,在海拔较低的区域则为增加趋势.在所有雪坑中,Na+和Cl-具有非常好的正相关性,Cl-/Na+为1.24~1.61,略高于海水中的值(1.168),说明Cl-虽然主要来源与于海盐,但仍有一小部分为其它来源.非海盐SO42-在不同雪坑中显示出不同特征,对其是否能指示火山喷发等问题还有待于进一步探讨.
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