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Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

Chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2 & WANG Zheng1,3 1 state key laboratory of Loess and Quaternary Geology, institute.of Earth Environment, Chinese academy of sciences, Xi’an 710075, china 2 Xi’an Jiaotong University, School of Human Settlement and Civil engineering, Xi’an 710049, china 3 Graduate University of Chinese academy of sciences, Beijing 100049, china state key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China School of Human Settlement and Civil engineering Xi’an Jiaotong University Xi’an China Graduate University of Chinese academy of sciences Beijing China

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern china, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern china under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2‰ to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3‰ to 7.2‰ with average of 4.1‰; and (2) mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for {12. changes.

关键词：氮同位素物理性质化学性质环境论

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论青藏铁路修筑中的冻土环境保护问题

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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

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

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

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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.state key laboratory of Cryospheric sciences,cold and arid regions environmental and {12. research institute.Chinese academy of sciences,lanzhou 730000.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 1.31℃/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

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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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The research of three-dimensional numerical simulation of groundwater-flow: taking the Ejina Basin, Northwest china as example

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research in cold and arid regions 2009年第3期1卷 238-248页

作者： Qi Feng 1,2, HaiYang Xi 1, Wei Liu 1,3, JianHua Si 1,2, ZongQiang Chang 1,2, YongHong Su 1,2 1. cold and arid regions environmental and engineering research institute. Chinese academy of sciences, lanzhou, Gansu 730000. china. 2. Alashan Desert Eco-hydrology Experimental research Station, lanzhou, Gansu 730000. china. 3. state key laboratory of Hydrosciences and engineering, Tsinghua University, Beijing 100084, china. Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst 320 West Donggang Rd Lanzhou 730000 Gansu Peoples R China Alashan Desert Ecohydrol Expt Res Stn Lanzhou 730000 Gansu Peoples R China Tsinghua Univ State Key Lab Hydrosci & Engn Beijing 100084 Peoples R China

Water is a primary controlling factor for economic development and ecological environmental protection in the inland river basins of arid western china. And it is groundwater, as the most important component of total water resources, that plays a dominant role in the development of western china. In recent years, the use-ratio of surface water has been raised, the groundwater recharge rate from surface water has been reduced, and groundwater has been exploited on a large scale. This has led to the decline of ground-water levels and the degradation of eco-environments in the Heihe watershed. Therefore, the study on the change in groundwater levels in recent years, as well as simulating and predicting groundwater levels in the future, have become very significant for im-proving the ecological environment of the Heihe River Basin, to coordinate the water contradiction among upper, middle and lower reaches of Heihe River Basin and to allocate the water resources. The purpose of this study is to analyze the groundwa-ter-level variations of the Ejina region based on a large scale, to develop and evaluate a conceptual groundwater model in Ejina Basin, to establish the groundwater flow model using the experimental observation data and combining Modular Three-Dimensional Groundwater Flow Model (MODFLOW) and GIS software, to simulate the regional hydrologic regime in re-cent 10 years and compare various water-delivery scenarios from midstream, and to determine which one would be the best plan for maintaining and recovering the groundwater levels and increasing the area of Ejina oasis. Finally this paper discusses the pos-sible vegetation changes of Ejina Basin in the future.

关键词： groundwater flow model Ejina Basin MODFLOW Heihe River

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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 100039, china 3. key laboratory of Ice and cold Region Environment, cold and arid {12. environmental and engineering research institute. Chinese academy of sciences, lanzhou 730000. china 4. institute.of Surfacial Geochemistry, state laboratory of Mineral De- posits research, 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 1936 A.D., 1939 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.

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昆仑山垭口多年冻土区钻孔气体组分分析

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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、C3H8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、C3H8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δ13CCH42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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Black Carbon Deposition and High Asia Glaciers

Black Carbon Deposition and High Asia Glaciers

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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), cold and arid regions environmental and engineering research {12. Chinese academy of sciences, lanzhou 730000. china 3 {12.of Atmospheric Physics, Chinese 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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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 regions.

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

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

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

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第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会

作者： Jun-Ji Cao 1,Bai-Qing Xu 2,Jian-Qiao He3,Xian-Qin Liu3,Yong-Ming Han1 1 SKLLQG,institute.of Earth Environment,Chinese academy of sciences,Xi’an 710075,china 2 laboratory of Tibetan Environment and Land Surface Processes,institute.of Tibetan Plateau research,Chinese academy of sciences,Beijing 100085,china 3 state key laboratory of Cryosphere sciences,cold and arid regions environmental and engineering research institute.Chinese academy of sciences,lanzhou 730000.china

Carbonaceous aerosol concentrations were determined for samples collected from Muztagh Ata Mountain in western china from December 2003 to February *** carbon（EC） in total suspended particle（TSP） samples varied from 0.004 to 0.174 μg m-3（average = 0.056 μg m-3） while organic carbon（OC） and carbonate carbon（CC） ranged from 0.12.to 2.17 μg m-3 and below detection to 3.57 μg m-3,*** EC and OC concentrations occurred during the winter-spring seasons while CC concentrations were higher during the warmer *** accounted for～7% of the total carbon（TC = EC + OC + CC） during spring and summer and 11% during autumn and winter;EC was the smallest carbonaceous fraction except in winter when CC was the ***/EC ratios varied from 2.9 to 32.1（average = 10.0）,and strong correlations between OC and EC（R2:0.75 to 0.77） in spring and winter suggest their cycles are coupled,but lower correlations in summer（0.39） and autumn（0.57） suggest that biogenic emissions and secondary OC become important as temperatures *** of in air parcel back trajectories indicate that about 0.05 μg m-3 EC,0.42 μg m-3 OC,and 0.10 μg m-3 CC were transported from outside *** Ata has EC concentrations nearly as low as those in polar areas;these may represent a background level for inland *** annual EC concentration was fall in the range and close to the lowest bound of EC contents that recovered from ice core drilled in Muztagh Ata glaciers.

关键词： Elemental carbon Organic carbon Carbonate carbon Aerosol Ice core Remote Atmosphere

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