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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and resources science, sichuan normal University, {4. 610066, sichuan, china 2. Institute of Mountain Hazards and environment, Chinese Academy of sciences, {4. 61004., sichuan, china 3. Graduate University of the Chinese Academy of sciences, Beijing 10004., china 4. Information Center of Land and resources department of sichuan Province, {4. 61004., sichuan, china The Faculty of Geography and resources {1. Sichuan Normal University Chengdu Sichuan China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of the Chinese Academy of sciences Beijing China Information Center of Land and resources {1. of sichuan Province Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1.92 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1.92 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan University Journal of Natural sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3,5 1. Institute of Mountain Hazards and environment, Chinese Academy of sciences , chengdu 61004., sichuan,{4. 2. Graduate University of Chinese Academy of sciences, Beijing 10004.,{4. 3. sichuan Institute of Land Resource Management, chengdu 61004., sichuan ,{4. 4. department of resources and environment science, sichuan normal University ,{14.,{4. 5. College of Information Engineering, chengdu University of Technology, chengdu 610059, sichuan,{4. Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of sciences Beijing China sichuan Institute of Land Resource Management Chengdu Sichuan China department of {1. and environment science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1.95 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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Ecological Footprint and Ecological Security Evaluation in the Upper Min River Basin

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Wuhan University Journal of Natural sciences 2005年第4期10卷 641-646页

作者： TU Jian-jun 1, 2 1. School of resources and environment science, Southwest china {4. University, Chongqing 4.0715, china 2. Institute of Mountain Hazards and environment, Chinese Academy of sciences, chengdu 61004., sichuan, china School of resources and {1. science Southwest China Normal University Chongqing China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China

On the basis of the ecological footprint (EF) model, this paper studied theecological security in the Upper Min River Basin ecosystem. The result shows that with 2. 038 2 hm^2per capita ecological capacity (0. 4.2 2 hm^2 higher than per capita EF) ,and 1.5 825 hm^2 ecologysurplus , the ecosystem in Upper Min River is generally secure at present. But the arable land isoverweighed and omens an eco-security crisis. Meanwhile, problems such as low forest coverage rate,severe loss of water and soil,enlargement of arid-valley area, frequent occurrence of mountainhazards and degradation of pastures have been major threats to the eco-security of this region. Thecalculation result of ten-thousand-yuan ( RMB) GDP shows that the use of natural {1. isextensive, and there will be a rapid increase tendency of EF in the future. In order to maintain thepresent eco-security, the ways of use natural {1. must be improved in the Upper Min RiverBasin.

关键词： ecological security ecological footprint ecological capacity quantitativeevaluation the Upper Min River Basin

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Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 1.7Cs technique

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Chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of environmental Change and Natural Disaster, the Ministry of Education of china, Beijing normal University, Beijing 100875, china 2. Institute of Desert Research, Chinese Academy of {4.s, Lanzhou 730000, china 3. Institute of Mountain Hazards and environment, Chinese Academy of {4.s, chengdu 61004., china 4. department of Physics, sichuan Union University, chengdu 61004., china Key Laboratory of environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-1.7 (1.7Cs) associated with the nuclear weapon tests during the 1.50s and 1.60s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 1.7Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 1.7Cs reference inventories of 982.1. and 2 376.04.Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 1.7Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 4. years have been revealed, i.e. the shrub coppicedunes (S1. and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4. S6 and S7) and dry farmlands (S5) suffered erosion only. By using 1.7Csmodel, the average wind erosion rates for shrub coppice

关键词： 1.7Cs technique Qinghai-Tibetan Plateau wind erosion.

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Studies on Barriers for Promotion of Clean Technology in SMEs of china

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Chinese Journal of Population,resources and {1. 2005年第1期3卷 9-17页

作者： Peng Sizhen , Liu Yan , Shi Han 1.2 & Zhong Ping 3 1. The Administrative Centre for china’s Agenda21. Beijing 1.0089, china 2. Yale School of Forestry & environmental Studies, New Haven CT 0651., the U.S.A. 3. department of environmental science and Engineering, sichuan University, chengdu sichuan 61.065, china The Administrative Centre for china’s Agenda21 Beijing 100089 China Yale School of Forestry and environmental Studies New Haven CT 06511 United States department of {1.al science and Engineering Sichuan University Chengdu Sichuan 610065 China

After more than 1. years efforts on awareness raising and promotion, the concept of cleaner production (CP) has been adopting as a strategic approach to balance economic benefits and environmental protection for{1.’s industries. However, it is also found that clean technology is difficult to be adopted and implemented in Chinese Small and Medium-sized Enterprises (SMEs) because of certain barriers. This paper investigates these barriers among three stakeholders--governments, enterprises and experts. The Analytic Hierarchy Process (AHP) was employed to prioritize the relative importance of the twenty fine-selected barriers, which were classified into four barrier categories. The findings reveal that the exterior barriers of policy and financial barriers should be stressed rather than the inner barriers of technical and managerial barriers, although they are also very important. Absence of incentives on economic policies, lax enforcement of environmental regulations and high initial capital cost were the most important barriers to adoption of Clean Technologies (CT) in{1..

关键词： Cleaner Production Clean Technologies Barrier Study Small and Medium Enterprises

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Denitrification in tidal flat sediment, Yangtze estuary

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science{1. Chemistry 2007年第6期50卷 812-820页

作者： WANG DongQi1.2, CHEN ZhenLou1. XU ShiYuan1. DA LiangJun1. BI ChunJuan1.& WANG Jun1.1.School of resources and {1. science, East china {4. University, Shanghai 200062, china 2 School of Life science, East china {4. University, Shanghai 200062, china School of resources and {1. science East China Normal University Shanghai China School of Life science East China Normal University Shanghai China

Sediment denitrification rates at six Yangtze River estuary tidal flat locations(mudflats and salt marshes)were measured from July 2003 to October *** winter and summer,spatial distribution of denitrification rates was not great in the Yangtze estuary,while in spring and autumn,denitrification rates had a great spatial distribution because of the human activity *** temporal change of denitrification rates was *** ranged from 0.2 to 36.4.umolN·m^(-2)·h^(-1.,and were higher in the *** annual average of sediment denitrification rate was 1..2±1..3 mu molN · m^(-2)· h^(-1.in the middle tidal flat and 1..1.±9.4. mu molN·m^(-2)·h^(-1.in the low tidal flat in the Yangtze *** analysis indicated that the temperature was the primary factor controlling the process of denitrification(significant positive correlation,P1.;at the same time,the content of sediment total nitrogen(TN)and the molar ratio of sediment carbon and nitrogen(C/N)had significant positive correlation(P<0.05)and negative correlation(P<0.05)with denitrification rates,*** the Yangtze estuary,increasing of water salinity had no significant inhibition of denitrification because of the wide change range of water salinity.

关键词： Yangtze estuary, tidal flat sediment, denitrification, effect factors

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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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science{1. Earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4.1. Faculty of Earth science and State Key Laboratory of Geological Processes and Mineral resources, china University of Geosciences, Wuhan 4.0074. china 2. Institute of resources & environments, Henan Polytechnic University, Jiaozuo 4.4.03, china 3. department of Computer science, South-Central University for Nationalities, Wuhan 4.0074. china 4. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china china University of Geo{1.s Henan Polytechnic University South-Central University for Nationalities Tongji University

Studies show positive shifts of inorganic and organic carbon isotope values (δ 1.Ccarb and δ 1.Ckerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.1.0}(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 1.%)) values from 0.01. to 0.1.0}, TOC values from 0.02% to 0.21., V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1.2,3, Feng Zhaodong4.and Gong Huili1.2(1. MOE and Key Laboratory of {1. environment and GIS of Beijing, Beijing 1.0037, china 2. Key Laboratory of 3D information Acquisition and Application, The Capital normal University, Beijing 1.0037, china 3. department of Economics & Management of Huizhou University, Huizhou 51.007, china 4. Key Laboratory of Western china’s environmental Systems, Ministry of Education, Lanzhou University, Lanzhou 730000, china) MOE and Key Laboratory of resources {1. and GIS of Beijing Beijing 100037 China

Ages of the stratigraphic boundary MIS1.2 and MIS3/4.of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1.2 and MIS3/4.are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1.2 is 1..5 kaB.P. and MIS3/4.is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1. 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—1..5 kaB.P. and 1..5 kaB.P.—59.8 kaB.P.; Model 3: 1..5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS1.0} age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

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Study on ground temperature change and characteristic response of engineering geology of permafrost along Qinghai-Tibet Railway

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science{1.(Technological sciences) 2003年第Z1期46卷 78-90页

作者： PAN Weidong, WANG Quancai, YU Shaoshui & ZHANG Xiaoyan department of Mechanics, School of Physical science and Technology, Lanzhou University, Lanzhou 730000, china Institute of Mountain Hazards and environment, Chinese Academy of sciences and Ministry of Water resources, chengdu 61004., china State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions environment and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, china sichuan Provincial Communications department, chengdu 61004., china Lanzhou Univ Dept Mech Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water resources Chengdu 610041 Peoples R China Chinese Acad Sci State Key Lab Frozen Soil Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China sichuan Prov Commun Dept Chengdu 610041 Peoples R China

Along with the global warming in the recent scores of years, comparatively big changes have taken place in the weather and other environmental conditions of the permafrost area in the Qinghai-Tibet Plateau, and very big changes have also occurred in the engineering geological conditions of the permafrost area. Based on a large volume of field survey data, this paper discusses the regularities of horizontal and vertical distribution of permafrost, with its focus of analysis on the temperature change characteristics of the soil in different frozen-soil zones, as well as presents simulation analysis and research for the engineering geologic characteristic response changes that would occur in the future when the temperature of the frozen soil in different zones rises by 1.and 2.6℃ respectively, which will have a tremendous impact on the stability of constructional work.

关键词： Qinghai-Tibet Railway, permafrost, ground temperature, engineering geological characteristic.

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Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1.2, Ge Yuhui1. Cai Yuanfeng2 and Zhang Xuefeng3(1. Faculty of resources & {1., Southwest Petroleum University, chengdu 61.500, china 2. State Key Laboratory for Endogenic Metal Deposit Research, Nanjing University, Nanjing 21.093, china 3. department of Natural resources & Technology Information, china University of Petroleum, Beijing 1.224., china) Faculty of resources & {1. Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China department of Natural {1. & Technology Infor- mation China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 323℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 4.0oC for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

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