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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3. ZHANG Yili1, BAI Wanqi1, liu Yanhua4, BAO Weikai5, liu Linshan1, 2.& ZHENG Du1 1. {2. of geographic {2. and {3. resources research, chinese academy of sciences, beijing 100101, china 2. Graduate School of the chinese academy of sciences, {12. 10003., china 3. College of resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, {12. 100862. china 5. Chengdu {2. of Biology, chinese academy of sciences, Chengdu 610041, china 1. institute of geographic {2. and {3. resources research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. College of resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Study of attenuation depths for MODIS bands in the Bohai Sea in china

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Acta Oceanologica Sinica 2009年第5期28卷 39-48页

作者： liu Ying LI Guosheng institute of geographic {2. and {3. resources research Chinese Academy of Science Beijing 100101 China Xinjiang institute of Ecology and Geogrphy Chinese Academy of Science Urumqi 830011 China

An attenuation depth is defined for remote sensing purposes as a depth above which 90% of the arising light leaving the water surface is originated. The deeper the attenuation depth, the more information of water is detectable by remote sensing, then the more precise information of water is extracted. Meanwhile, the attenuation depth is helpful to know water layer （by its thickness） from which remote sensing will be able to extract information. A number of investigators are using the moderate resolution imaging spectroradiometer （or MODIS） for remote sensing of ocean color. It is necessary to have a rough idea of the effective attenuation depth of imagery in each of the spectral bands employed by the MODIS. The attenuation depth is directly determined from MODIS data. Though analyzing the spectral distribution of the attenuation depth on 7 August 2.03.and the seasonal variation of the attenuation depth （551 nm） in the Bohai Sea indicated that： the spectral distribution of the attenuation depth for the spectral range between 400 to 700 nm is single-peak curve, and it’s similar and difference in different regions is consistent with other scholars’ results of zoning, moreover, it supports the Bohai Sea is Case 2.water; the maximum attenuation depth shifts toward longer wavelengths, liking the red shift, with increase of turbidity of water, just like the maximum attenuation depth in the outside of the northwest coast of the Bohai Sea and the Bohai Strait is at 53.nm, in the central of the Bohai Sea is at 551nm, in the region controlled by the Huanghe （Yellow） River, the region impacted by the old Huanghe River, the western side of the Liaodong Bay and the eastern side of the Liaodong Bay is at 555 nm; the seasonal change of the attenuation depth is the largest in the summer, followed by the fall, and the ranking of winter and spring in different regions is distinct. The attenuation depth in different regions is dissimilar： the order of the attenuation depth in different

关键词： attenuation depth MODIS Bohai Sea

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2.1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan,{2. 2. Graduated School of the chinese academy of sciences, beijing 10003.,{2. chinese academy of {2. Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) Graduated School of the chinese academy of sciences Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

Environmental Implication of Intensive Farming Practices on North china Plain

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chinese Journal of Population,resources and Environment 2005年第3期3卷 11-20页

作者： Zhen Lin 1, Zhou Hailin 2.& Xie Gaodi 1 1 institute of geographic {2. and {3. resources research, chinese academy of sciences, beijing 100101 , china 2.The Administrative Center for china's Agenda 2., {13. 100089, china institute of geographic {2. and {3. resources research Chinese Academy of Sciences Beijing 100101 China The Administrative Center for china’s Agenda 2. Beijing 100089 China

The current pressure on production resources of North china Plain, such as land and water to feed the growing population, necessitates the assessment of the sustainability of farming practices. This study focuses on the sustainability of farming practices related to groundwater and soil fertility management. The assessment is based on selected site-specific key indicators and their established threshold limits. The current farming practices in the study area are clearly unsustainable. Only about 6% of the surveyed farm households practice sustainable farming. The study stresses that farming practice, which is economically sustainable, should not be promoted at the cost of environment. Holistic strategies need to be developed and implemented that aim at balanced use of inputs, which satisfy both productivity and environmental concerns.

关键词： sustainability indicators threshold values farming practices environmental implication

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. wang Yuejun1, FAN Weiming1, liu Dunyi3. SHI Yuruo3.& MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou {2. of Geochemistry,{2., Guangzhou 510640,{3. 2. Graduate University of{2., beijing 10003.,{3. 3. SHRIMP isotope Laboratory, chinese academy of Geological sciences, beijing 10003.,{3. 4. {2. of Geology and Geophysics,{2., beijing 10002.,{3. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-13.) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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 geographic {2. and {3. resources research,chinese academy of {2.,beijing 100101,china 2.National Development and Reform Commission,beijing 10082.,china institute of geographic {2. and {3. resources research 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

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. {3. and natural resources research,chinese academy of {3.,beijing 100101,{12. 2.Graduate University of chinese academy of sciences,beijing 100049,{12. 3.institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of {3.,beijing 100044,{12. 4 institute of Tibetan Plateau research,chinese academy of {3.,beijing 100085,{12. 5 institute of Desert and Meteorology,{12. Meteorological Administration,ürümqi 83.002.{12. institute of geographic {2. and {3. resources research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China institute of Desert and Meteorology China Meteorological Administration ürümqi 830002 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

Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2. XIE Zheng-Hui1,* 2. liu Qian1 and XIA Jun 3.1LASG, {3. of Atmospheric Physics,{2., {2. 10002. ({3.). 2.College of Water resources and Environment, Hohai University, Nanjing 2.0098 ({3.)3.{3. of {13.al Science & natural resources,{2.,{12. ({3.) institute of Atmospheric Physics chinese academy of {2. beijing 10002. （china）. 2.College of Water {2. and Environment Hohai University Nanjing 2.0098 （china）3.institute of {2.al Science & {3. resources beijing 100101 （{2.）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3.) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.2.° × 0.2.° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2.(1991-2.00) and future climateB2.(1991-2.00) with A2.and B2.being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2.and B2. theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2.3.-2.70. In addition,under future climate A2.and B2. an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3. model

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., liu Jing 3., YUN Jinku 1 , SUN Liling 2., liu Riping 1 , ZHANG Jun 2.& {2. Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. Center for Condensed Matter Physics, {2. of Physics,{3., beijing 100080, china 3. BSRF, {2. of High Energy Physics,{3., beijing 10003., china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.