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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. institute of Geographic sciences and {2. resources research, Chinese Academy of sciences, beijing 100101, China 2. Graduate School of the Chinese Academy of sciences, beijing 100039, China 3. College of resources and Environment, Southwest Agricultural University, Chongqing 400716, China 4. The Ministry of science and Technology, P. C. China, beijing 100862. China 5. Chengdu institute of Biology, Chinese Academy of sciences, Chengdu 610041, China institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of sciences Beijing China College of resources and Environment Southwest Agricultural University Chongqing China The Ministry of science and Technology P. C. China Beijing China Chengdu institute of Biology Chinese Academy of Sciences 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.

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Interannual and Interdecadal Variability of Atmospheric Water Vapor Transport in the Haihe River Basin

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Pedosphere 2005年第5期15卷 585-594页

作者： WEI Jie LIN Zhao-Hui XIA Jun TAO Shi-Yan institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 （China） institute of geographical {2.s and natural resources research Chinese Academy of Sciences Beijing 100044（China）

The seasonal mean atmospheric precipitable water and water vapor transport over the Haihe River Basin （HRB） in North China with a focus on their interannual to interdecadal variability, and then the relationships of the interannual and interdecadal variability of the water cycle over the HRB to the Pacific Decadal Oscillation （PDO） and E1 Nino-Southern Oscillation （ENSO） phenomena were investigated using the observational and National Centers for Environmental Prediction （NCEP） reanalysis data. There was a strong interdecadal variability for the water cycle （such as precipitation and water vapor transport） over the region, with an abrupt change occurring mostly in the mid 1970s. The intensity of the East Asian summer monsoon largely affected the atmospheric water vapor transport. Generally, the net meridional convergence of the water vapor flux over the region was relatively large before 1965, and it declined gradually from then on with a further notable decrease since mid 1970s. Zonal water vapor transport was similar to meridional, but with a much smaller magnitude and no noteworthy turning in the mid 1970s. Results also suggested that the wind field played an important role in the water vapor transport over the HRB before the mid 1960s, and the interdecadal variability of the water cycle （precipitation, water vapor transport, etc.） in the summer was related to the PDO; however, interannual variation of the water vapor transport could also be related to the ENSO phenomena.

关键词： interannual variability interdecadal variability Haihe River Basin water vapor transport

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Cosmogenic ^(2.)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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science China Earth sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2.DING Lin2.LAI QingZhou2.& HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,Chinese Academy of sciences,{2. 10002.,China 2.Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau research,Chinese Academy of sciences,{2. 100085,China 3 institute of Mineral resources research,China Metallurgical Geology Bureau,{2. 10002.,China Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of Mineral resources {2. China Metallurgical Geology Bureau Beijing China

Various sources of 2.Ne and 2.Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in China,of cosmogenic 2.Ne and 2.Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 2.Ne and ***-heating experiments show that concen-trations of cosmogenic 2.Ne and 2.Ne in summit bedrock samples R92.2.and R92.3 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.2.±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2.0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 2.Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

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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,{2. 10002.,China 2.Strategic research Center for Oil and natural Gas,The Ministry of Land and resources of China,{2. 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 = 2..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, 2.0.5°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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Response of remotely sensed Normalized Difference Water Deviation Index to the 2.06 Drought of eastern Sichuan Basin

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science China Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2. GAO ZhiQiang3 & PENG Jian4 1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, China 2.National Satellite Meteorological Center, China Meteorological Administration, beijing 100081, China 3 institute of Geographic {2.s and natural resources research, Chinese Academy of {2.s, beijing 100101, China 4 School of Environmental {2.s, Peking University, beijing 100871, China School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China School of Environmental sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2.01―2.06 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2.06 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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The challenge of wide application of information and communication technologies to traditional location theory

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Journal of geographical sciences 2013年第2期23卷 315-330页

作者： SONG Zhouying LIU Weidong Key Laboratory of Regional Sustainable Development Modeling of the Chinese Academy of sciences institute of Geographic sciences and {2. resourcesResea—rch CASBeijing100101China

The wide application of information and communication technologies （ICTs） has been argued to be critical to spatial transformation of firms. Recent advances in the studies along this line have challenged traditional location theory. The existing literature, however, focuses mainly on the impacts of ICTs on Iocational conditions and industrial spatial distribution. The dynamics behind such changes have not yet been given sufficient attention by geographers. Given this background, this paper investigates the impact of new ICTs on traditional location theory and the dynamics of industrial re-location that are enabled by new ICTs, based on data collected from an investigation of 178 firms. The paper argues that the application of new ICTs has been a key location factor in the information age, and that the time-cost is becoming critical to the spatial organization of firms, particularly as a result of a shorter product life and mass customization, among other dynamics.

关键词： information and communication technologies location factor time-cost

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The types and characteristics of man-induced sediment disaster

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Journal of geographical sciences 2002年第4期12卷 495-504页

作者： JIN Desheng, SHI Changxing, CHEN Hao, ZHANG Ouyang(Inst. of Geographic sciences and natural {2. research, cas, beijing 100101, China) Inst. of Geographic sciences and natural {2. research CAS 北京 100101

The man-induced sediment disaster includes material erosion, transportation and accumulation by human activities. It possesses special attribute in sociology and disaster science. In accordance with human activities, geomorphologic location, behavior and particular, the man-induced sediment disaster can be divided into 4 types: the drainage network, slope and gully, channel and plain-estuary-coastline. Each type includes erosion, transportation, accumulation, complexity and cascading. Based on human activity, geomorphology, sediment mechanics and catastrophology, the man-induced sediment disaster is characterized as follows: (1) accelerating tendency with {2. zoning back-ground; (2. non-order characters by blind action without special technical training; (3) gradually and sharply changing with human environment vibration; and (4) complexity and non-linear figure, etc. One of the reasons leading to man-induced sediment disaster is human environment vibration.

关键词： man’s dynamics sediment disaster type character

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Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS

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Journal of geographical sciences 2001年第3期11卷 313-320页

作者： GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (State Key Laboratory of resources and Environment Information System, institute of Geographic {2.s and natural resources research, cas, beijing 100101, China) State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS

Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two key factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones.

关键词： GIS the Yellow River Delta saline-alkali land zonation

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The Relation of Department Components and Activity in Spatial Information Infrastructure

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Wuhan University Journal of natural sciences 2001年第Z1期6卷 460-466页

作者： Yi Shan zhen 1, Zhou Li zhu 1,Cheng Ji cheng 2. Li Qi 2.1.Department of Computer science and Technology,Tsinghua University, beijing 100084, China {2. of Remote Sensing and geographical Information System,Peking University,beijing 1008 Department of Computer science and Technology Tsinghua University Beijing China institute of Remote Sensing and geographical Information System Peking University Beijing China

Spatial Information Infrastructure (SII) facilitates the sharing, interoperability and integration of geographical information among department components of a region or a country. The SII is developed and shared by different department components. The relation of department components is a fundament for collaborating tasks and information exchange in SII. There are two kinds of department components, one is the provider which produces geospatial data of SII, other is the consumer which uses geospatial data of SII. The consumer includes two kinds of user, one is the user which only uses and does not produce geospatial data in SII, other is the special user which not only uses but also produces geospatial data in SII. The provider includes different hierarchies corresponding to different kinds of geospatial data in SII. All providers in the hierarchies form provider actor set PA. All consumers also form consumer actor set CA. The sender recipient relation SR and SRI are defined on Cartesian product of PA and CA. Five tasks and information flow in SII demonstrate the geospatial data acquisition, information production, management, and application among department components. The tasks and their sub tasks are subdivided activities. Each activity corresponds to the relation SR or RSI. The activity along with the relation of provider and consumer forms a scheme of geographical information exchange between department components.

关键词： geographical information exchange relation activity information infrastructure

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Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in China

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Journal of Mountain science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China Graduate University of the ChineseAcademy of sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2.08 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method

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