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Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4 1. Faculty of Earth Science,china university of Geosciences,Wuhan 430074,china 2. School of Environmental Studies,china university of Geosciences,Wuhan 430074,china 3. SKLLQG,institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,university of Minnesota,MN55455,USA 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. School of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Nd isotope as the tracer of seawater evolution of early Miocene in the eastern Pacific Ocean

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Chinese Science Bulletin 2003年第B06期48卷 106-110页

作者： LIU Jihua~(1,2,3), CHEN Lirong~1, WANG Yingxi~4 & HAN Jianxiu~5 1. institute of Oceanology, Chinese Acadcmy of ences, Qingdao 266071. china 2. Key Lab of Marine Sedimentology and Environmental Geology, First institute of Oceanograpgy, State Oceanic Administration, Qingdao 266061. china 3. Graduate School, Chinese Academy of Sciences, Beijing 100039. china 4. Modern Analysis Center, nanjing university. nanjing 210093. china 5. Guangzhou Marine Investigation Bureau, Guangzhou 510760. china 1. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 2. Key Lab of Marine Sedimentology and Environmental Geology First Institute of Oceanograpgy State Oceanic Administration 266061 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China 4. Modern Analysis Center Nanjing University 210093 Nanjing China 5. Guangzhou Marine Investigation Bureau 510760 Guangzhou China

Fifty-six samples of nannofossil ooze were collected from Core PC5794 in the northern equatorial Pacific at 5 cm intervals. With the methods of mass spectrometer (VG354) and ICP, the Nd isotopic compositions (εNd(t)), Mn contents and Mg/Sr ratios of carbonate phase have been analyzed. CaCO3 contents of bulk sediments were obtained by dissolution of 0.5 mol/L HCl. Based on these data, the high-resolution εNd(t) profile of seawater in early Miocene with core depth(or time) have been established. The values of εNd(t) range from -6.2 to -2.97 and 4 fluctuation cycles existed during 24.06-22.02 Ma. 4 low εNd(t) values (about -6.4) correspond to high CaCO3 contents, which implicates that there were 4 cold epochs or 4 times of Antarctic Bottom Water activity. They occurred at the time of 24.06 Ma, 23.85 Ma,22.88 Ma and 22.26 Ma, respectively. High εNd(t) values correspond to the high Mn contents and high values of Mg/Sr ratio, which indicates the existence of 4 intense hydrothermal activity periods during 24.06-22 Ma, the durations of them are 4.05-23.98 Ma, 23.69-23.15 Ma, 22.74-22.37 Ma and 22.06-22.02 Ma, respectively.

关键词：同位素钕示踪原子海水演化中新世太平洋微化石分光计持续期海水样品

The Formation Mechanism of Hydrogeochemical Features in a Karst System During Storm Events as Revealed by Principal Component Analysis

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地学前缘 2009年第S1期16卷 33-34页

作者： Pingheng Yang Daoxian Yuan Kuang Yinglun,Wenhao Yuan,Peng Jia,Qiufang He 1.School of Geographical Sciences,Southwest university,Chongqing 400715,china. 2.Laboratory of Geochemistry and isotope,Southwest university,Chongqing 400715,china 3.The Karst Dynamics Laboratory,Ministry of Land and Resources,institute of Karst Geology,Chinese Academy of Geological Sciences,Guilin 541004,china

The hydrogeochemical parameters of Jiangjia Spring,the outlet of Qingrnuguan underground river system(QURS) in Chongqing,were found responding rapidly to storm events in late April,2008.A total of 20 kinds of hydrogeo... 详细信息

关键词： rainfall principal component analysis(PCA) soil erosion agricultural activities karst hydrogeochemical feature Qingmuguan

Water Security Problem in North china: research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA Shao-Feng Key Laboratory of Water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072（China） Center for Agricultural Resources research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North china with the aim of highlighting key waterresources management and water security issues for the long-term development of North china. Three key problemsrelated to water resources and security issues in North china in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North china are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth china farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North china’s water security.

关键词： environmental change North china water cycle water resources water security

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回灌量与井深关系的试验研究

水电能源科学 2010年第2期28卷 50-53页

作者：王彬彬李伟温忠辉闵星马超群张鉴河海大学水文水资源学院江苏南京210098 南京水利科学研究院江苏南京210029

采用室内砂槽模型试验研究了回灌井回灌过程中水丘变化规律与井深对补给效率的影响,通过观测地下水位变化,分析了不同井深条件下水丘变化规律,测定了不同时刻的回灌流量、出流量及总回灌量,基于试验的有效性分析了井深变化对总回灌量的... 详细信息

采用室内砂槽模型试验研究了回灌井回灌过程中水丘变化规律与井深对补给效率的影响,通过观测地下水位变化,分析了不同井深条件下水丘变化规律,测定了不同时刻的回灌流量、出流量及总回灌量,基于试验的有效性分析了井深变化对总回灌量的影响。结果表明,回灌井与水丘位置关系决定水丘壅堵的效应,单位井深回灌量最大值出现于包气带与包气带井—潜水井的临界井深处。

关键词：人工回灌砂槽试验水丘变化总回灌量单位井深回灌量

Nitrogen and oxygen isotope budget balance in tropospheric N_2O

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Chinese Science Bulletin 1999年第S2期44卷 99-100页

作者： XU Wenbin~(1,2) and HONG Yetang~1 1. State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, china 2. institute of Environment and Resources Chemistry, Zhejiang university, Hangzhou 310027, china State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of Environment and Resources Chemistry Zhejiang University Hangzhou 310027 China

THK N2O is an important greenhouse gas. In the steady state the stable isotopic composition of nitrogenand oxygen in tropospheric N2O is balanced by isotopically light N2O emitted from soils and oceans andisotopically heavy N2O as return flux from the stratosphere. However, no such balance was reached incalculations given by Kim and Craig. This serious discrepancy lied in the fact that only soil and oceanic sources were considered in Kim and Craig’s calculation and N2O emission from tropical forest soil wastaken as the global soil contribution. Progress since the 1990s in identifying additional sources of atmospheric N2O as well as in the estimation from various types of soil allows us to make more realistic assessment of nitrogen and oxygen isotope balance budgets in tropospheric N2O. In this note, modification willbe proposed of atmospheric N2O nitrogen and oxygen isotope budgets to Kim and Craig’s calculation. The static balance of nitrogen and oxygen isotopes in tropospheric N2O is expressed

关键词： N2O nitrogen stable isotope oxygen stable isotope budget balance troposphere.

Uncertain Decision-Making Analysis Method Based on Information Entropy Principles

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Uncertain Decision-Making Analysis Method Based on Informati...

Proteomic Analysis of Pyrene Stress-Responsive within Plant Roots

2009中国控制与决策会议

作者： JIN Ju-liang~(1,2),SHEN Rui~2,ZHANG Ming~3,ZHOU Cheng~2,PAN Zheng-wei~4 1.Chengdu institute of Plateau Meteorology,CMA,Chengdu 610072,china. 2.School of Civil Engineering,Hefei university of Technology,Hefei 230009,china. 3.College of hydrology and Water Resources,hohai university,nanjing 210098,china. 4.School of Natural Resources and Environmental Engineering,Hefei university of Technology,Hefei 230009,china.

＜正＞Benefit and loss matrix of uncertain decision-making analysis reflects both the objective information structure of uncertain decision-making problem and the risk information of benefit chance and loss chance faced by decision-maker. The transform vector consisted of the natural state weights is quantitative expression of uncertain decision-making rule adopted by *** essential for resolving uncertain decision-making problem is how to transform benefit and loss matrix into compressed real vector with one dimension,where the biggest weight of the vector corresponds to the best action *** the information of benefit and loss matrix has been not mined sufficiently using the common methods for uncertain decision-making *** in this paper,the whole difference weights of the natural states can be determined using projection pursuit method,the local difference weights of the natural states can be determined directly using information entropy and accelerating genetic algorithm based fuzzy analytic hierarchy process,and the two kinds of weights can be combined into comprehensive weights according to the minimum relative information entropy principle, which can form a new uncertain decision-making analysis method based on information entropy principles,named UDM-IEP for *** application results show that the information of benefit and loss matrix can be mined more sufficiently using UDM-IEP than the common methods,that the decision-making information can be more provided by UDM-IEP than by the common methods,that decision-maker can actively or safely choose the best scheme based on the comparison between of benefit chance risk and loss chance risk contained in the benefit and loss matrix,that UDM-IEP is both simple and general,that its computation result is objective and stability,and that UDM-IEP can be widely applied in theory and practice of systems engineering.

关键词： uncertain decision-making analysis method benefit and loss matrix information entropy principle combination weight projection pursuit fuzzy analytic hierarchy process genetic algorithm

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Proteomic Analysis of Pyrene Stress-Responsive within Plant ...

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

The 2nd International Conference on Asian-European Environmental Technology and Knowledge Transfer

作者： XU Shengyou2,3,4,CHEN Yingxu1,RUAN Aidong3,ZHANG Wei2,LI Feng1,CHEN Xincai1(1,Department of Environmental Engineering,Zhejiang university,Hangzhou 310029,china 2,Resources and Environmental Engineering institute,East china university of Science and Technology,Shanghai 200237,china 3,State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering,hohai university,nanjing 210098 4,School of Life and environmental Science,Huangshan university,Huangshan 245000,china)

Phytoremediation is a new method for removing polycyclic aromatic hydrocarbons from the environment.A study was conducted to investigate accumulation of pyrene and protein changes in maize of Zea mays L responding to the stress of 1week exposure to pyrene in the growth media.A group of three 5-week maize plants was allowed to grow in a nutrient solution of different pyrene concentration（0,0.1,1,and 10 mg/L） for 1 week,the roots were then taken for proteomic *** proteins in the roots were extracted and separated by two-dimensional gel electrophoresis;28 protein spots were different from those of the control *** comparisons of isoelectric point,molecular weight and abundance showed 14 up-regulated protein spots,four newly induced protein spots,6 down-regulated protein spots,and lost four *** ten proteins of different molecular weight were subjected to trypsin digestion and then peptide separation by MALDI-TOF mass spectrometry;only six of them matched the database at molecular weights of 12.69,21.89,22.30,43.14,57.22 and 102.61 *** six matched proteins were centromere protein-like protein,putative heat shock protein,putative GTP-binding protein,6-phosphofructo-2-kinase,cytochrome P450,and fructose-2,*** study results have demonstrated the benefits of the proteomic approach in phytoremediation of PAHs and also provided new insights into pyrene degradation related proteins in maize roots.

关键词： proteomic maize pyrene accumulation stress response

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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