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

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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

新疆哈密八大石森林上限树轮记录的温度变化信息

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山地学报 2009年第4期27卷 402-410页

作者：徐国保刘晓宏陈拓安文玲侯书贵李忠勤中国科学院寒区旱区环境与工程研究所冰冻圈科学国家重点实验室

本研究采集新疆哈密地区八大石西伯利亚落叶松森林上限树芯样本,建立标准宽度年表。通过树木年轮-气候响应分析,发现标准年表序列反映了该地生长季(5～9月)的月平均温度及月平均最低温度信息,且该序列与前人的研究结果对比具有较好的一... 详细信息

本研究采集新疆哈密地区八大石西伯利亚落叶松森林上限树芯样本,建立标准宽度年表。通过树木年轮-气候响应分析,发现标准年表序列反映了该地生长季(5～9月)的月平均温度及月平均最低温度信息,且该序列与前人的研究结果对比具有较好的一致性。树轮宽度序列主要反映出了1885年之前以冷期为主,1885年之后以暖期为主,且暖期延续时间变长,20世纪后半期增温的趋势。该序列与天山冰川进退的时间较为一致,同时也发现该序列极值与当地蝗灾具有很好的对应,与亚洲近两百年来的大型火山喷发事件具有很好的一致性,由此可以推测该年表在一定程度上捕捉到了冰川进退、火山事件的环境信息。

关键词：哈密树木年轮标准年表温度

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...

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

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 {12. 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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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

干旱区不同荒漠植被土壤水分的时空变化特征分析

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水土保持研究 2005年第6期12卷 231-234页

作者：马海艳龚家栋王根绪程国栋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兰州730000

土壤水分是连接气候变化和植被覆盖动态的关键因子.以额济纳地区为研究对象,通过在6～10月间,于四种荒漠植被类型:胡杨林地,人工梭梭林,苜蓿地及戈壁观测点,布置管式时域反射仪(TDR)水分测定仪进行定点、定位观测,研究了上游放水前后,... 详细信息

土壤水分是连接气候变化和植被覆盖动态的关键因子.以额济纳地区为研究对象,通过在6～10月间,于四种荒漠植被类型:胡杨林地,人工梭梭林,苜蓿地及戈壁观测点,布置管式时域反射仪(TDR)水分测定仪进行定点、定位观测,研究了上游放水前后,同一观测点不同深度及不同土地利用条件下土壤水分的时空分布和动态变化状况.分析表明:潜水蒸发对土壤水的补给作用越强,剖面水分条件越好;受土壤特性影响,垂直剖面含水量自下而上并不是严格递减的,对外界环境条件变化所做出的反应也不同,其中戈壁及人工梭梭林地土壤水分在垂直剖面上分布较均匀;胡杨林地和苜蓿地各剖面土壤水分差异较大.

关键词：时域反射仪(TDR) 土壤水分时空分布动态变化

Chemical composition and Effect of tourism in aerosol samples collected at typical temperate glacier region from the southeastern Tibetan Plateau,china

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Chemical composition and Effect of tourism in aerosol sample...

博斯腾湖流域山区地表径流对近期气候变化的响应

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： Zhang Ningning1,He Yuanqing1,2,Pang Hongxi1,3,He Xianzhong4,Wang Linlin5(1.state key laboratory of Cryspheric science,cold and arid regions environmental and engineering research institute,CAS,lanzhou 730000,{12. 2.institute of Tibetan Plateau research,CAS,Beijing 100029,{12. 3.state key laboratory of Marine Geology,Tongji University,Shanghai 200092,{12. 4.The Jade Dragon Snow Mountain Tourism Development Administrative Committee,Lijiang,674100,{12. 5.department of geography and tourism BinZhou university,Binzhou,256600,{12.)

Aerosol samples were collected at 4706m a.s.l from ablation zone of Baishui glacier No.1,***,from May to June,*** concentration of Cl-,NO3-,SO42-,Na+,k+,Mg2+,and Ca2+ was determined by *** average aerosol loading is 25.45neq scm-1,NO3-and Na+ are the dominant soluble ions in the aerosol,accounting for 39%and 21%of total average aerosol loading *** circulation reduces the concentration of ions except Cl-,Ca2+ and k+,and the concentration of Ca2+ has a good relationship with relative *** of NO3-is attributed to motor exhaust emissions and their photochemical production,although the concentration of NO3-is affected by south Asia human activities *** correlation coefficients between soluble species suggest Cl-,Na+ and k+ come from sea salt aerosol,and SO42-,Mg2+ and Ca2+ is from regional *** addition,under the influence of developing tourism,the concentration of NO3-is higher than reported measurements in southwest monsoon regions,but the concentration of SO42-is lower.

关键词： Aerosol Lijiang Mt.Yulong Temperate glacier

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山地学报 2010年第2期28卷 206-211页

作者：孙占东 Christian Opp 王润高前兆中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室马尔堡大学地理系中国科学院城市环境研究所中国科学院寒区与旱区环境与工程研究所

近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注。鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和... 详细信息

近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注。鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和冰川等方面与出山径流变化关系进行比较来揭示径流突变原因。结果表明,产流区平均径流深与降水量关系的转变是引起出山径流异常波动直接原因;进一步的冰川变化分析显示,径流深的波动主要由冰川融水径流变化引起:20世纪80年代中期后的温度上升加速了山顶冰川消融,导致1987～2002年的径流增加和湖泊水位升高;1984～2000年间,流域山顶冰川面积消退近40%,随着分布在较低海拔,对温度升高最敏感的中小冰川的消失,冰雪消融带来的径流增加效应开始减弱;2002年后,在流域气温、降水等变化并不显著的情况下,出山径流量却急剧降低,反映了特定冰川分布条件地区在气候变暖中融水径流先升后降的现象。

关键词：天山博斯腾湖气候变化地表径流水文响应

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保护冻土的保温原理

上海师范大学学报（自然科学版） 2003年第4期32卷 1-6页

作者：程国栋张建明盛煜陈继上海师范大学城市与旅游学院上海200234 中国科学院寒区旱区环境与工程研究所兰州730000

在多年冻土地区修筑路堤、设置保温层是保护路堤下多年冻土上限不变甚至上升的隔热保温方法,其保温效果取决于隔热层对下部多年冻土年平均地温和温度较差的改变状况.作者阐述了保温方法的工作原理,并依据该原理探讨了最小路堤高度和最... 详细信息

在多年冻土地区修筑路堤、设置保温层是保护路堤下多年冻土上限不变甚至上升的隔热保温方法,其保温效果取决于隔热层对下部多年冻土年平均地温和温度较差的改变状况.作者阐述了保温方法的工作原理,并依据该原理探讨了最小路堤高度和最大路堤高度存在的可能性及其适用范围.北麓河试验场的观测资料较好地验证了理论探讨.

关键词：多年冻土地温较差保温层路堤高度

Quantitative estimation of climate change effects on potential evapotranspiration in Beijing during 1951-2010

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Journal of Geographical Sciences 2014年第1期24卷 93-112页

作者： LIU Haijun LI Yan JOSEF Tanny ZHANG Ruihao HUANG Guanhua College of Water Sciences Beijing Normal University Beijing 100875 China College of Water Resources and Civil engineering China Agricultural University Beijing 100083 China institute of soil Water and Environmental Sciences Agricultural Research Organization The Volcani CenterP. O. Box 6 Bet Dagan 50250 Israel state key laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100048 China

℃ Climate change is likely to affect hydrological cycle through precipitation, evapotranspiration, soil moisture etc. In the present study, an attempt has been made to study the climate change and the sensitivity of estimated evapotranspiration to each climatic variable for a semi-arid region of Beijing in North china using data set from 1951 to 2010. Penman-Monteith method was used to calculate reference crop evapotranspiration （ETo）. Changes of ETo to each climatic variable was estimated using a sensitivity analysis method proposed in this study. Results show that in the past 60 years, mean temperature and vapor pressure deficit （VPD） were significantly increasing, relative humidity and sunshine hours were significantly decreasing, and wind speed greatly oscillated without a significant trend. Total precipitation was significantly decreasing in corn season （from June to September）, but it was increasing in wheat season （from October to next May）. The change rates of tem- perature, relative humidity, VPD, wind speed, annual total precipitation, sunshine hours and solar radiation were 0.42℃, 1.47%, 0.04 kPa, 0.05 m.s-1, 25.0 mm, 74.0 hours and 90.7 MJ.m-2 per decade, respectively. In the past 60 years, yearly ETo was increasing with a rate of 19.5 mm per decade, and total ETos in wheat and corn seasons were increasing with rates of 13.1 and 5.3 mm per decade, respectively. Sensitivity analysis showed that mean air temperature was the first key factor for ETo change in the past 60 years, causing an annual total ETo increase of 7.4%, followed by relative humidity （5.5%） and sunshine hours （-3.1%）; the less sensitivity factors were wind speed （0.7%）, minimum temperature （-0.3%） and maximum temperature （-0.2%）. A greater reduction of total ETo （12.3%） in the past 60 years was found in wheat season, mainly because of mean temperature （8.6%） and relative hu- midity （5.4%）, as compared to a reduction of 6.0% in ETo during corn season due to sunshinehours （-6.9%）, relative

关键词： climatic variables reference crop evapotranspiration Penman-Monteith equation changing trend sensitivity analysis