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Plausible impact of global climate change on water resources in the Tarim River Basin

Science China Earth sciences 2005年第1期48卷 65-73页

作者： CHEN Yaning & XU Zongxue Xinjiang institute of Ecology & Geography, chinese academy of sciences, Urumqi 830011, China College of Environmental sciences, beijing Normal University, beijing 100875, China Xinjiang institute of Ecology & Geography Chinese Academy of Sciences Urumqi China College of Environmental sciences Beijing Normal University Beijing China

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

关键词： climate change, hydrological change, temperature, precipitation, streamflow, Tarim River.

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Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science China Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4, WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese academy of sciences, Xining 810008, China 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, China 3 Nanjing institute of Geology and Mineral resources, Nanjing 210016, China 4 State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 5 State Key Laboratory for Mineral Deposits research, Department of Earth sciences, Nanjing University, Nanjing 210093, China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Nanjing institute of Geology and Mineral resources Nanjing China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China State Key Laboratory for Mineral Deposits research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

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Spatial pattern of land cover change in China's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2 1 State Key Laboratory of Environment and resources Information System, institute of geographical sciences and resources research, chinese academy of sciences, beijing 100101, China 2 Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China State Key Laboratory of Environment and resources Information System Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Hong Kong Baptist University Kowloon Tong Hong Kong

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of China based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2) the establishment of land cover change classes based on an unification land cover classification theme, (3) the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, China. The results showed the land cover had undergone a remarkable change from 1991 to 2002 in the study area (the changed area was over 30%). Rapid increase of cropland (12.5%), built-up area (131.4%) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile ecosystem of China’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of China remote sensing human activities

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Problems for water resources development in typical small karst drainage basins and countermeasures

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Journal of geographical sciences 2000年第2期10卷 168-176页

作者： WAN Hong-tao, XIE Chuan-jie, SHI Yun-liang (LREIS, institute of geographical sciences and natural resources, chinese academy of sciences, beijing 100101, China, Department of Urban and Resource, Nanjing University Nanjing 210093, China) 中科院地理与资源所资源与环境信息系统国家重点实验室北京南京大学江苏南京

In karst area water deficit is one of the main factors constraining sustainable economic development. In 1979 the comprehensive karstic observational field station was set up in Houzhai drainage basin located,\ in Puding county of Guizhou Province, which can represent most of the small karst drainage basins on the dividing line of the Guizhou Plateau. Geomorphology, water resources and water chemistry were investigated and observed. Based on comparisons of water supply with water demand and analysis of the main problems in water exploitation and utilization. it is found out that the water deficiency was not directly caused by the scarcity of natural water resources. The true reason is the insufficient capacity of water supply caused by the dismatch of the water and soil water resources which can be dealt with by building more irrigation works. Some solutions such as to build scientific basis for water exploitation and utilization and sustainable economic development in karst drainage basins on dividing line of the Guizhou Plateau.

关键词： small karst drainage basin water resources comparison of water supply and demand sustainable exploitation and utilization

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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South China: Implications for palaeocean temperature

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Progress in natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits research and Center for Marine Geochemistry research, Department of Earth sciences, Nanjing University, Nanjing 210093, China 2. Tarim Oilfield Company Exploration & Development research institute, Ku’erle 841000, China 3. institute of Mineral resources, chinese academy of Geological sciences, beijing 100037, China) State Key Laboratory for Mineral Deposits research and Center for Marine Geochemistry research Department of Earth Sciences Nanjing University Nanjing 210093 China Tarim Oilfield Company Exploration & Development research institute Ku'' erle 841000 China institute of Mineral resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South China. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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Relationship Between Soil Properties and Different Fractions of Soil Hg

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Pedosphere 2001年第3期11卷 257-262页

作者： WU HONGTAO YU GUIFEN QING CHANGLE and CHEN TONGBIN Southwest Agricultural University, Chongqing 400716 (China) institute of Geographic sciences and natural resources, the chinese academy of sciences, beijing 100101 (China) institute of Soil Science, th 西南农业大学重庆 400716 中科院南京土壤所江苏南京 210008 中科院地理科学与资源所北京 100101

Correlation and path analysis methods were used to study the relationship between soil properties and the distribution of different soil Hg fractions with nine representative soils from Chongqing, China. Results showed that clay (< 2 m) could increase water-soluble Hg (r = 0.700*). Soil organic matter (OM) could enhance the increase of elemental Hg (r = 0.674*). The higher the base saturation percentage (BSP), the more the residual Hg (T = 0.684*). Organic Hg, the sum of acid-soluble organic Hg and alkali-soluble Hg, was positively affected by silt (2-20 μm) but negatively affected by pH, with the direct path coefficients amounting to 1.0487 and 0.5121, respectively. The positive effect of OM and negative effect of BSP on organic Hg were the most significant, with the direct path coefficients being 0.7614 and -0.8527, respectively. The indirect effect of clay (< 2 μm) via BSP (path coefficient = 0.4186) was the highest, showing that the real influencing factor in the effect of clay (< 2 μm) on acid-soluble organic Hg was BSP. Since the available Hg fraction, water-soluble Hg, was positively affected by soil clay content, and the quite immobile and not bioavailable residual Hg by soil BSP, suitable reduction of clay content and increase of BSP would be of much help to reduce the Hg availability and Hg activity in Hg-contaminated soils.

关键词： different fractions soil Hg soil properties

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Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science China Earth sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of Mineral resources, institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, China 2. beijing institute of Geology for Mineral resources, beijing 100012, China Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of Mineral resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China beijing institute of Geology for Mineral resources Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North China Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

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Process and mechanism of arable land change in Hebei Province during the past 50 years

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Journal of geographical sciences 2001年第4期11卷 47-52页

作者： XU Yue-qing (institute of geographical sciences and natural resources research, CAS, beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China )

Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable *** paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc.

关键词： decrease in arable land area changing process mechanism Hebei Province

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传染病多点触发智慧化监测预警系统关键技术专家共识

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中华医学杂志 2024年第32期104卷 2995-3009页

作者：中国医学科学院北京协和医学院群医学及公共卫生学院北京大学公共卫生学院中国疾病预防控制中心传染病管理处四川大学华西公共卫生学院中国科学院地理科学与资源研究所首都医科大学附属北京地坛医院中华医学会公共卫生分会中国医学科学院北京协和医学院群医学及公共卫生学院北京大学公共卫生学院中国疾病预防控制中心传染病管理处四川大学华西公共卫生学院中国科学院地理科学与资源研究所首都医科大学附属北京地坛医院中华医学会公共卫生分会

有效的传染病监测预警系统是公共卫生安全体系的重要组成部分, 对预防与控制传染病暴发流行至关重要, 提升监测预警能力是推动疾病预防控制事业高质量发展的当务之急。专家组结合公共卫生与预防医学、临床医学、管理学、数据科学、计算... 详细信息

有效的传染病监测预警系统是公共卫生安全体系的重要组成部分, 对预防与控制传染病暴发流行至关重要, 提升监测预警能力是推动疾病预防控制事业高质量发展的当务之急。专家组结合公共卫生与预防医学、临床医学、管理学、数据科学、计算机科学等多学科专家的研究成果与实践经验, 经过反复多轮专家研讨, 形成了传染病多点触发智慧化监测预警系统关键技术专家共识。本共识内容主要包括传染病多点触发智慧化监测预警系统的相关概念和定义, 关键技术框架, 多渠道监测预警数据来源、获取与治理, 预警方法分类, 多点触发智慧化监测预警关键流程及路径, 多点触发预警及综合研判, 预警信号响应以及预警效果评价等方面, 以期为传染病多点触发智慧化监测预警系统建设及应用提供技术参考。

关键词：传染病监测预警多点触发智慧化

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Paleomagnetic study on orogenic belt:An example from Early Cretaceous volcanic rocks,Inner Mongolia,China

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Science China Earth sciences 2004年第12期47卷 1127-1133页

作者： REN Shoumai 1,2 ,ZHU Rixiang 1 ,HUANG Baochun 1 ,ZHANG Fuqin 1 & WANG Hongqiang 1 1.institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,China 2.Strategic research Center for Oil and natural Gas,The Ministry of Land and resources of China,beijing 100034,China Strategic research Center for Oil and natural Gas The Ministry of Land and Resources of China Beijing China chinese academy of sciences Institute of Geology and Geophysics Beijing China

We report paleomagnetic results for Early Cretaceous lava flows collected from the Suhongtu area of Inner Mongolia, the middle part of the Tianshan-Mongolia Fold Belt (TMFB). Rock-magnetic experiments for different lava flows indicate that the main magnetic mineral is pseudo-single-domain (PSD) magnetite. The characteristic high-temperature remanence com- ponent is isolated by thermal demagnetization temperature steps between 300°C and 585"C, which yields a mean direction of D = 23.6°, I=56.0° with α 95 = 2.3°. We interpret this high-temperature remanence component as primary magnetization based mainly upon the petrographic analysis, which shows that the shape of magnetite crystal is relatively rounded square or polygon without internal reflection and deuterogenous phenomenon. The correspond- ing pole of the high-temperature remanence component is at 71.1°N, 200.5°E with A 95 = 2.7°. This Early Cretaceous pole is in good agreement with those for Siberia, North China, and Inner Mongolia, suggesting that these continental blocks had already sutured together in the Early Cretaceous, which would further provide constraints on better understanding of the formation and evolution of the TMFB.

关键词： orogenic belt, paleomagnetism, Suhongtu of Inner Mongolia, Eurasia.

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