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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, China

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Science China Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, China 2. Department of Geography, Nanjing University, Nanjing 210093, China 3. School of Earth sciences and resources, China University of Geosciences, beijing 100083, China institute of Geographic sciences and natural resources research Chinese Academy of Sciences Beijing China School of Earth sciences and resources China University of Geosciences Beijing China Department of Geography Nanjing University Nanjing China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, China, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (<10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, China.

Spatial and environmental effects on plant communities in the Yellow River Delta,Eastern China

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Journal of Forestry research 2009年第2期20卷 117-122页

作者： SONG Chuang-ye1, 2, LIU Gao-huan1, LIU Qing-sheng1 1 institute of Geographic sciences and Nature resources research, chinese academy of sciences, beijing 100101, China 2 Graduated School of chinese academy of sciences, beijing 100039, China institute of Geographic sciences and Nature resources research Chinese Academy of Sciences Beijing China Graduated School of chinese academy of sciences Beijing China

Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling *** showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix *** vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble *** the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total *** variation and spatial-structured environmental variation explain 11.8%, and 2.2%, *** 40.8% of undetermined variation is attributed to biological and stochastic factors.

关键词： detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis

Farming and forestry land use changes in China and their driving forces from 1900 to 1980

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Science China Earth sciences 2005年第10期 181-191页

作者： GE Quansheng & DAI Junhu institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, China

A variety of agricultural and forestry land use materials, especially those in the first half of 20th century, were collected. According to land use change in this period, the whole country is demarcated into seven regions, Northeast China, North China, Northwest and Loess Plateau, Southeast and Coastal Region, Southwest China, Qinghai-Tibetan Plateau, Inner Mongolia and Xinjiang, in proper order by using Cluster Analysis. The farming and forestry land use change in these regions were analyzed. The results show that the total cultivated land areas increased in this period, especially in the 1950s and 1960s the cultivated land area increased more significantly, but differed in different regions, and the most rapid increasing rate was 2.63 percent a year. On the other hand, the forestry land area was increasing in most parts of this period, especially after 1949. But in most regions, the decrease of forestry land area at the end of 1970s is also very obvious. It is regarded that the population increase, food production, natural disasters and some related government policies were among the main driving factors for farming and forestry land use change.

关键词： land use change cultivated land forestry land driving factors 20th century.

Urban Water Supply Industry Marketization of China in View of Public Water Service and Water Resource Management

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chinese Journal of Population,resources and Environment 2010年第2期8卷 55-60页

作者： Wang Yining 1,2 1.institute of Geographic Science and natural resources research,CAS,beijing 100101,China 2.Graduate School of the chinese academy of sciences,beijing 100049,China institute of Geographic Science and natural resources research CAS Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100049 China

Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some *** article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and *** efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and *** the end,an assumption on urban water price is put forward to help achieve the public water service equalization.

关键词： urban water supply industry marketization public water service water resource management

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,China

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chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, China 2. College of Earth sciences and resources, China University of Geo-sciences, beijing 100083, China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China College of Earth sciences and resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

Analysis of F, Al, Mn, Zn, Fe, Cu, Ca and Mg concentrations in brick teas from main producing areas in China

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chinese Journal of Geochemistry 2006年第S1期 80-81页

作者： Xiaoyu ZHAO, Wuyi WANG, Hairong LI, Fujian FENG, Lizhen WANG institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, China

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 natural 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 natural 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 2000 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 2000, 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 2000, 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.

LANDSCAPE ECOLOGICAL CONSTRUCTION IN RURAL CHINA:THEORY AND APPLICATION

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chinese geographical Science 2001年第2期11卷 104-114页

作者： XIAO Du-ning (Cold and Arid Regions Environmental and Engineering research institute, the chinese academy of sciences, Lanzhou 730000, P.R.China institute of Applied Ecology,the chinese academy of sciences, Shenyang 110015,P.R.China ) Cold and Arid Regions Environmental and Engineering research institute the Chinese Academy of Sciences Lanzhou P.R. China institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

In landscape with overpopulation, intensive management for economic production, and where even small natural-vegetation patches are scarce, ecological conservation generally must be developed in the course of economic development. Thus “landscape ecological construction” has evolved in China. This approach adds spatial elements and alters landscape pattern to strengthen inter-ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. Five examples of managed landscapes in China are presented: dike-pond systems in a river delta; multi-pond system in a rice paddy landscape; field-grass-wood grid system on unstable sand dunes; shelterbelt network in a crop field area; and field-grass-wood mosaic system on highly erodible hilly farmland. These indicate that ecological conditions can be improved along with increased economic production. Altering landscape structure and ecological flows by introducing small landscape elements in distinct spatial patterns is considered a key to the results. This reshaping of the land has focused on changing patch size, regularity of arrangement, biological and hydrological corridors, and networks, the matrix and grain size. It suggests that such changes can increase negative feedbacks and increase stability. Finally, planning and design principles are pinpointed for the landscape ecological construction process.

关键词： landscape planning ecological construction rural China

Cosmogenic ^(21)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,beijing 100029,China 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau research,chinese academy of sciences,beijing 100085,China 3 institute of Mineral resources research,China Metallurgical Geology Bureau,beijing 100025,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 research China Metallurgical Geology Bureau Beijing China

Various sources of 21Ne and 22Ne 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 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.22±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： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains