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Journal of Environmental sciences 2010年第2期22卷 283-289页

作者： Bin Wu,Tongbin chen Center for Environmental Remediation,institute of {2. {3. and Natural Resources research,chinese academy of sciences,beijing 100101,china. Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Follow-up investigation on hair arsenic concentration was conducted in an arsenic heavily polluted area of southern china in 2.02.and 2.06. The results showed that the geometric mean of hair arsenic concentration decreased from 2.95 mg/kg in 2.02.to 1.78 mg/kg in 2.06, when the percentage of the population with levels over 1 mg/kg only decreased from 93.4% in 2.02.to 80.5% in 2.06. Over this four-year period, the population with high arsenic concentrations decreased significantly while there was no obvious change in hair arsenic concentration for people who had relatively low concentrations. In terms of age distribution, young and old people had higher hair arsenic concentrations than the middle-aged. All of these results showed that it is difficult to reverse the negative impact of arsenic pollution on human health. Arsenic pollution has a long-term continuous influence on the health of local residents.

关键词： arsenic human health soil contamination hair arsenic

china's Regional Policies:Progress of the 11^(th) Five Year Plan Period and Prospect of the 12.(th) Five Year Plan Period

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chinese Journal of Population,Resources and Environment 2011年第2期9卷 90-96页

作者： chen xuebin1,2.1.institute of {2. {3. and Natural Resources research,chinese academy of sciences,beijing 100101,china 2.National Development and Reform Commission,beijing 10082.,china institute of geographic {2. and Natural Resources {3. Chinese Academy of Sciences Beijing 100101 China National Development and Reform Commission Beijing 100824 China

During the 11th Five Year Plan period,china improved its policy system for the overall strategy of regional development,and established and completed the policies intended for the promotion of regional cooperation and ***,regional development in china took on a series of positive changes such as the enhancement of *** the 12.h Five Year Plan period,china will fully implement and continuously improve the policy measures for development in its four major regions,strengthen differentiated guidance to different regions in line with the planning for major function-oriented zones,and accelerate the establishment of basic systems that facilitate coordinated regional development.

关键词： regional policy progress prospect

Thresholds of geographic environmental elements in sediment yield of drainage basins

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Science china Earth sciences 2005年第2期48卷 230-240页

作者： chen Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan {2. of {3. sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china {2. of Forestry Science, chinese academy of Forestry Science, {12. 100091, china research Center for Eco-Environment sciences, chinese academy of sciences, {12. 100085, china Computing {2. of Science and Engineering, North china Electric Power University, {12. 102.06, china institute of geographic {2. and Natural Resources {3. Chinese Academy of Sciences Beijing China institute of Forestry Science Chinese Academy of Forestry Science Beijing China research Center for Eco-Environment sciences Chinese Academy of Sciences Beijing China Computing institute of Science and Engineering North China Electric Power University Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science china(Technological sciences) 2005年第S2期48卷 116-128页

作者： chen Liangfu1,2. GAO Yanhua1,3. chenG Yu1,3. WEI Zheng1,3. XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, {2. of Remote Sensing Applications, chinese academy of sciences, beijing 100101, china 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.002., china 3. Graduate University of chinese academy of sciences, beijing 10003., china 4. beijing research {2. of Uranium Geology, beijing 100875, china 5. {2. of geographic sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate University Chinese Academy of Sciences Beijing 100039 China beijing research {2. of Uranium Geology Beijing 100875 China institute of geographic {2. and Natural Resources {3. Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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chinese Science Bulletin 2009年第13期54卷 2300-2308页

作者： chen Jin1,2.3.WANG LiLi1,4,5,ZHU HaiFeng1 & WU Pu1 1 institute of {2. sciences and Natural Resources research,chinese academy of sciences,beijing 100101,china 2.Graduate University of chinese academy of sciences,beijing 100049,china 3.institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044,china 4 institute of Tibetan Plateau research,chinese academy of sciences,beijing 100085,china 5 institute of Desert and Meteorology,china Meteorological Administration,ürümqi 83.002.china institute of geographic {2. and Natural Resources {3. Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China institute of Desert and Meteorology China Meteorological Administration Ürümqi China

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2.00,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2. of the *** reconstructed results indicated a cold span of 153.years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4, WANG LiLi1,2.3. chen Jin5, DUAN JianPing1,4, SHAO XueMei1,2.& chen KeLong6 1 {2. of geographic sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china 2.{2. of Tibetan Plateau research, chinese academy of sciences, {12. 100085, china 3.{2. of Desert and Meteorology, china Meteorological Administration, Urumqi 83.002. china 4 Graduate University of chinese academy of sciences, {12. 100049, china 5 {2. of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, {12. 100044, china 6 School of Life and Geography sciences, Qinghai Normal University, Xining 810008, china institute of geographic {2. and Natural Resources {3. Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China institute of Desert and Meteorology China Meteorological Administration Urumqi China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China School of Life and Geography sciences Qinghai Normal University Xining China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

Channel characteristics and formation mechanism of Ganjiang River

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Journal of geographical sciences 2000年第4期10卷 129-134页

作者： chen Zhi-qing (institute of {2. {3. and Natural Resources research, chinese academy of sciences, beijing 100101, china) 中科院地理科学与资源所北京

Relative straight channel of the middle and upper reaches of Ganjiang has been formed due to thecontraction of mountains and hills being composed of bedrocks on both banks of the river. But however, At the lower reaches, branching channel predominates due to limited contracting force of the river banks as the evolution and development of branching channels are closely related with locations and controle effect of nodal points. There are sufficient water containing less sediments in Ganjiang River where the sharp rise and fall of the flow discharge makes the grain size of the particles rather coars. Gravels mingled with sand dominate the channel bed and components of central bars are also much coarser than those in sandy bed of the middle and lower reaches of the Yangtze River.

关键词： channel characteristics genetic mechanism comparison with middle and lower Yangtze Ganjiang River

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and chen Jinping3.1. institute of Geodesy and Geophysics, {2., Wuhan 43.077, china 2. Graduate School of {2., beijing 10003., china 3. Department of Precision Instrument and Mechanology, Tsinghua University, beijing 100084, china) institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School Chinese Academy of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS Ionospheric eclipse factor Ionospheric influence factor

Sandstorms and desertification

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Journal of geographical sciences 2000年第3期10卷 99-102页

作者： chen Zhi-qing1, ZHU Zhen-da2.(1.institute of {2. sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china 2. institute of Dsert research, chinese academy of sciences, beijing 100101, china)

Sandstorm is a frequently occurred disastrous weather in northern china. The increasing occurrence frequency recently, especially the much more frequently occurred sandstorms with high intensity in the spring of 2.00 have caused great loss to national economy. The combination of strong wind, exposed sandy soil on ground surface and unstable air current constitutes the necessary conditions for the sandstorms. However, the accelerated desertification process resulting from irrational human economic activities is responsible for the accelerated sandstorms. The effective measures to mitigate sandstorm lie in strengthening desertification control and eco-environmental protection.

关键词： sandstorm generating conditions desertification eco-environmental protection

Relationship between erosion and sediment yield in drainage basins of loess gully-hilly areas

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Journal of geographical sciences 2001年第1期11卷 71-79页

作者： chen Hao (institute of {2. {3. and Natural Resources research, CAS, beijing 100101, china) institute of geographic {2. and Natural Resources {3. CAS Beijing China

From a long-term point of view, the balance between erosion and sediment yield in a drainage system can basically realize, i.e., the delivery ratio can be close to 1. However, substantial variations among individual rainfall events or between annual delivery ratio exist, causing frequent sediment retaining or re-erosion and re-delivery of the retained sediments in a short period of time. Thus the delivery ratio will be 1 or > 1. The sediment delivery ratio is closely related to the spatial distribution of rainfall and magnitude of rise and fall of peak flood and that of runoff depth in the drainage system. Delivery ratio of single event in a drainage system and changes of delivery capacity of silt-laden runoff in various classes of gullies can be expressed by transformation mechanism of shear force of a single rainstorm event with flood resulting from increase and decrease of peak flood per unit area.

关键词： delivery ratio interaction flood and geomorphology dynamic mechanism rainstorm flood