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Distribution of δ18O in surface snow along a transect from Zhongshan Station to Dome A,East Antarctica

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Distribution of δ18O in surface snow along a transect from ...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： DING MingHu~(1,2,3.),XIAO CunDe~2,JIN Bo~4,REN JiaWen~2,QIN DaHe~2 & SUN WeiZhen~2 1 Division of Cenozoic Geology and Environment,institute of Geology and Geophysics,chinese academy of Sciences,Beijing 100029,China 2 {3. key laboratory of Cryospheric Sciences,cold and arid regions environmental and engineering research institute,chinese academy of Sciences,lanzhou 73.000,China 3.Graduate University of chinese academy of Sciences,Beijing 100049,China 4 chinese Arctic and Antarctic Administration,Beijing 100860,China

Surface snow samples were collected during the 14th(1997/1998)and 24th(2007/2008)chinese National Antarctica research Expeditions along a transect from Zhongshan Station to Dome *** stable oxygen isotope ratios of these samples were measured to investigate their relationships with temperature and geographical parameters(latitude,longitude,altitude and distance to the coast).The results reveal a strong positive correlation(R=0.945)betweenδO and mean annual temperature,with a gradient of 0.84‰℃,which is a little higher than that in Terre Adelie *** analyses also show that theδO of surface snow is strongly correlated with distance to the coast(R=0.942),latitude(R=0.942),and altitude(R=0.941).But no significant correlation was found betweenδO and longitude in study *** should be the most important factor influencing theδO distribution because of distinctive ***δO-altitude and T-altitude gradients along this transect are determined to be-1.1‰/100 m and 1.3.℃/100 m,respectively.

关键词： Antarctica ITASE isotope Dome A δ18O CHINARE

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土地沙质荒漠化过程的土壤分形特征

土壤学报 2002年第6期39卷 877-881页

作者：赵文智刘志民程国栋中国科学院寒区旱区环境与工程研究所

土壤特性往往是沙质荒漠化的一个指征，也是不同形式的土地沙质荒漠化导致的生态系统功能改变的一个非常重要的测度。粒度组成是土壤结构和生产力的重要方面。

关键词：土壤分形特征土地沙质荒漠化分形维数粒径重量分布

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长江源区五道梁的大气质量状况

山地学报 2009年第4期27卷 411-417页

作者：李韧赵林丁永建杨文季国良中国科学院青藏高原冰冻圈观测试验研究站冰冻圈科学国家重点实验室中国科学院寒区旱区环境与工程研究所

大气质量状况是研究大气对太阳辐射能衰减程度的一个重要方面。利用江河源区五道梁能量收支站1993.09～1999-12的辐射观测资料及1993.09～1995-05 MS-120太阳光度表的观测资料计算了五道梁地区的大气浑浊度,分析了该地的大气质量状况。... 详细信息

大气质量状况是研究大气对太阳辐射能衰减程度的一个重要方面。利用江河源区五道梁能量收支站1993.09～1999-12的辐射观测资料及1993.09～1995-05 MS-120太阳光度表的观测资料计算了五道梁地区的大气浑浊度,分析了该地的大气质量状况。结果表明,江河源区五道梁的大气洁净,1994～1999年间五道梁地区的ngstr m浑浊度β、D/S、全波段浑浊度TG有增大的趋势,晴空大气透射比及紫外辐射有减小的趋势。

关键词：长江源区大气浑浊度透射比紫外辐射

Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an arid River Valley, SW China

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China state key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern China. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing {3..

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity environmental variability China

Paleosandstorm characteristics and lake evolution history deduced from investigation on lacustrine sediments——The case of Hongjiannao Lake, Shaanxi Province

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Science Bulletin 2005年第20期 101-107页

作者： SHEN Ji1, WANG Yong1,2, YANG Xiangdong1, ZHANG Enlou1, YANG Bao3.& JI Junfeng4 1. Nanjing institute of Geography and Limnology, chinese academy of Sciences, Nanjing 210008, China 2. Graduate School, chinese academy of Sciences, Beijing 10003., China 3. key laboratory of Ice and cold Region Environment, cold and arid regions environmental and engineering {{13. institute, chinese academy of Sciences, lanzhou 73.000, China 4. institute of Surfacial Geochemistry, state laboratory of Mineral De- posits {{13., Department of Earth Sciences, Nanjing University, Nanjing 210009, China

Sediment cores from desert lakes serve as good records of the frequency and intensity of sandstorms in his- tory. By multi-proxy analysis of grain-size, magnetic suscep- tibility, TOC and Rb/Sr ratio, the paleosandstorm character- istics and lake evolution history in Yulin Area for the past 80 years. are discussed in this article. It is revealed that Hong- jiannao Lake formed in about 1928 A.D. and in its initial stage sandstorms were prevalent with three extremes taking place in 193. A.D., 193. A.D. and 1941 A.D.. During the ex- pansion period of 1952―1960 A.D., inflow waters to the lake increased sharply and a lot more weathered materials were carried into the lake. The frequency and intensity of sand- storms have reduced a lot since 1960s and the “double peaks” feature of the grain-size frequency curve has changed into the “single peak” feature. Study on the catchment ecol- ogy of the lake shows that the occurrence of sandstorms has been effectively restrained by the forest plantation and water and soil conservation.

关键词： lacustrine sediment paleosandstorm characteristics lake evolution history Hongjiannao Lake.

Black Carbon Deposition and High Asia Glaciers

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Black Carbon Deposition and High Asia Glaciers

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Jing Ming1, 2, Cunde Xiao2, Zhencai Du3. Xingguo Yang2 1 China National Climate Center (CNCC), Beijing 100081, China 2 state key laboratory of Cryospheric Sciences (SKLCS),{3., {3. academy of Sciences, lanzhou 73.000, China 3.institute of Atmospheric Physics, {3. academy of Sciences, Beijing 100029, China

Black carbon (BC) is now concerned as one of the most significant factors impacting environment and climate mainly from anthropogenic activities. One aspect of its impacts is that the accelerated snow and ice in nature when BC is deposited in their surfaces. Since 2000, 18 High Asia glaciers have been surveyed for black carbon deposition 22 times, and numerous snow samples and ice cores have been collected by researchers. However, most of the results were interpreted individually in papers. Here, we assemble the data and discuss the distribution of BC deposition and its impacts on the melting of the glaciers through radiative forcing. We find that BC distribution on the surfaces of High Asia glaciers primarily depends upon their elevations (i.e., higher sites have lower concentrations) and then on regional BC emissions associated with surface melting conditions. BC concentrations in High Asia glaciers are similar to the Arctic and western American mountains but are significantly less than heavy industrialized areas such as northern China. Although Himalayan glaciers, which are important due to their water resources, are directly facing the strong emissions from South Asia, their mean BC is the lowest due to high elevations. A new finding indicated by ice core records suggested great valleys in the eastern Himalayan section are effective pathways for BC entering the Tibetan Plateau and makes increasing BC trends in the local glaciers. On average, BC deposition causes a mean forcing of ～6 W m-2 (roughly estimated 5% of the total forcing) in High Asia glaciers and therefore may not be a major factor impacting the melting of most glaciers.

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昆仑山垭口多年冻土区钻孔气体组分分析

天然气地球科学 2011年第6期22卷 1076-1081页

作者：杨玉忠吴青柏邓友生蒋观利张鹏中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室甘肃兰州730000

昆仑山垭口多年冻土区2个钻孔的气体组分和同位素数据显示,钻孔气体中烃类气体以CH4为主,含微量的C2H6、C3.8和C4H10。钻孔-1泥浆气体的C1/(C2+C3.值介于163.1 642之间;钻孔-2岩心和泥浆气体主要为CH4气体组分,未检出C2H6等气体组分,... 详细信息

昆仑山垭口多年冻土区2个钻孔的气体组分和同位素数据显示,钻孔气体中烃类气体以CH4为主,含微量的C2H6、C3.8和C4H10。钻孔-1泥浆气体的C1/(C2+C3.值介于163.1 642之间;钻孔-2岩心和泥浆气体主要为CH4气体组分,未检出C2H6等气体组分,同时δ13.CH42个钻孔的CO2含量低于15%,而且δ13.CCO2值介于-26.8‰～-20‰之间,小于-10‰,说明其为有机成因气。

关键词：昆仑山垭口气体组分多年冻土区

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论青藏铁路修筑中的冻土环境保护问题

水文地质工程地质 2002年第4期29卷 14-16,20页

作者：吴青柏施斌南京大学地球科学系地球环境计算工程研究所

本文通过研究已建青藏公路修筑过程中寒区冻土环境和生态环境的破坏特征 ,分析总结了寒区环境破坏对公路工程的影响。青藏公路工程修建活动极大地改变了冻土环境 ,使得多年冻土退化 ,上限加深 ,诱发了一系列冻胀、融沉、热融滑塌等冻融... 详细信息

本文通过研究已建青藏公路修筑过程中寒区冻土环境和生态环境的破坏特征 ,分析总结了寒区环境破坏对公路工程的影响。青藏公路工程修建活动极大地改变了冻土环境 ,使得多年冻土退化 ,上限加深 ,诱发了一系列冻胀、融沉、热融滑塌等冻融灾害 ,使得生态环境原本就很脆弱的寒区环境更加恶化 ,如植被退化、荒漠化等 ,同时 ,冻土环境的破坏也使得工程环境恶化 ,直接影响青藏公路正常交通运输。因此 ,在即将进行的青藏铁路修筑工程中 ,必须深入研究其对冻土环境的影响 ,对冻土环境问题和环境保护应予以足够的重视。

关键词：青藏铁路冻土环境冻融灾害荒漠化冻胀融沉植被退化

Concentrations,Seasonal Variations,and Transport of arbonaceous Aerosols at a Remote Mountainous Region in Western China

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Concentrations,Seasonal Variations,and Transport of arbonace...