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

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., sichuan,{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 resources 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 1995 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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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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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 {4., chengdu 610066, sichuan, china 2. Institute of Mountain Hazards and environment, Chinese Academy of sciences, chengdu 61004., sichuan, china 3. Graduate {4. of the Chinese Academy of sciences, Beijing 10004., china 4. Information Center of Land and resources department of sichuan Province, chengdu 61004., sichuan, china The Faculty of Geography and resources science 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 department 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 1992 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 1992 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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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 environment 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 165 825 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 resources 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 resources 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 137Cs 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 sciences, Lanzhou 730000, china 3. Institute of Mountain Hazards and environment, Chinese Academy of sciences, 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-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s 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 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 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 137Cs 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 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth environment, Chinese Academy of sciences, Xi’an 710075, china 2. department of Urban and {4. sciences, Nanjing university, Nanjing 210093, china 3. department of Earth sciences, Nanjing university, Nanjing 210093, china 4. department of Geography, Shaanxi normal university, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 6 department of Geography, Qinghai normal university, Xining 810008, china 7. Graduate School of the Chinese Academy of sciences, Beijing 100039, china SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate School of the Chinese Academy of sciences Beijing China department of Urban and resources sciences Nanjing University Nanjing China department of Earth sciences Nanjing University Nanjing China department of Geography Shaanxi Normal University Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China department of Geography Qinghai Normal University Xining China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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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 china(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 {4., Chinese Academy of sciences and Ministry of Water resources, chengdu 61004., china State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions {4. 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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A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of environment Beijing Normal University Beijing 100875 China department of Water environment China Institute of Water Resources and Hydropower Research Beijing100038 China department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 4..0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

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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 environment 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 100089, china 2. Yale School of Forestry & environmental Studies, New Haven CT 06511, the U.S.A. 3. department of environmental science and Engineering, sichuan university, chengdu sichuan 610065, 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 environmental science and Engineering Sichuan University Chengdu Sichuan 610065 China

After more than 10 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 china’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 china.

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 china 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 environment science, East china {4. university, Shanghai 200062, china 2 School of Life science, East china {4. university, Shanghai 200062, china School of resources and environment 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 18.2±12.3 mu molN · m^(-2)· h^(-1)in the middle tidal flat and 15.1 ±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,P<0.01);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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Flowering and Fruiting Phenology of 24.Plant Species on the North Slope of Mt. Qomolangma (Mt. Everest)

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Journal of Mountain science 2010年第1期7卷 45-54页

作者： ZHANG Liyun TURKINGTON Roy TANG Ya department of environmental sciences Sichuan University Muoziqiao Chengdu Sichuan 610065 P. R. China department of Botany & Biodiversity Research Center University of British Columbia Vancouver Canada

Phenological background information for alpine species is limited from extremely high altitudes. Flowering and fruiting phenology was monitored for 24.plant species at 5,180 m a.s.1, near the base camp area on the north slope of Mt. Qomolangma （Mt. Everest） in Tibet, western china. The dates of first flowering, peak flowering, end of flowering, first fruiting, peak fruiting and flowering period were recorded. There was a wide variation in onset of flowering, long flowering duration, a relative synchrony between the onset of flowering and fruiting, and one species was exclusively vegetative. These results suggest that the species have evolved various phenological strategies as adaptations to the short growing season with limited resources and pollinators in this harsh alpine environment at extremely high elevations. With a background of global warming, local plant species will represent an advancing trend in onset of flowering.

关键词： Alpine Global warming Phenology Qinghai-Tibet plateau

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