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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 resources Sciences, Nanjing {3., Nanjing 210093. china 3. Department of Earth Sciences, Nanjing {3., Nanjing 210093. china 4. Department of Geography, Shaanxi normal {3., Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, {14. 100029, china 6 Department of Geography, Qinghai normal {3., Xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, {14. 10003., china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. Department of Urban and resources 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

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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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 10003., china 3. college of resources and environment, Southwest Agricultural university, Chongqing 4.0716, china 4. The Ministry of Science and Technology, P. C. china, beijing 100862, china 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 61004., china 1. Institute of Geographic Sciences and Natural 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 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 9.4.1}. 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.

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Designing regional pattern for ecosystem restoration:A case study

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Science china(Technological Sciences) 2006年第z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, FU Bojie & LIU Shiling State Key Lab of Systems Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, beijing 100085, china Department of Water environment, china Institute of Water resources and Hydropower Research, beijing 10003., china School of environmental Sciences, beijing normal university, beijing 100875, china 1. State Key Lab of Systems Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. Department of Water environment China Institute of Water Resources and Hydropower Research Beijing 100038 China 3. School of environmental Sciences Beijing Normal University Beijing 100875 China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW china. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. ({4. Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4. Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

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Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural Sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2, LIU Chuang1, 3.1. Institute of Geographic Sciences and Natural resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Graduate {3. of Chinese Academy of Sciences, beijing 10004., china 3. college of resources Science and Technology, beijing normal {3., beijing 100875, china Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China college of resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2000,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2008 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2008. There were 12 63..54.hm2 cropland de-creased between 1993.and 2000,and 8 227.6 hm2 cropland de-creased between 2000 and 2008. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2 1. School of environmental Sciences, beijing normal {3.,{4., china 2. Institute of Geographic Science and Natural resources Research, beijing 100101, china beijing normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982—1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982 to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4.00 km3. the evapotranspiration of 3.00-3.00 km3. and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Estimation methods of eco-environmental water requirements: Case study

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Science china Earth Sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2, CUI Baoshan1 & LIU Jingling 1. School of environment, beijing normal {3.,{4., china 2. State Key Joint Laboratory of environmental Simulation and Pollution Control,{4., china 1. School of environment Beijing Normal University 100875 Beijing China 2. State Key Joint Laboratory of environmental Simulation and Pollution Control 100875 Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2010, 203., 2050) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84.1010m3.to 1.02×1011m3. the suitable water requirement ranges from 6.4.×1010m3.to 1.78×1011m3. the water shortage ranges from 9.1×109m3.to 2.16×1010m3.under the minimum water requirement, and it is from 3.07×1010m3.to 7.53.1010m3.under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2010, 203., 2050) are 4.4.×1010m3.1.73.1011m3. 5.99×10m3.2.09×1011m3. and 7.4.×1010m3.2.52×1011m3. respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

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The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological Sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2, WANG Yu3.& WANG Hongrui1 1. beijing normal university,{3., china 2. Institute of Geographic Science and Natural resources, Chinese Academy of Sciences, beijing 100101, china 3. Reconnaissance, Planning, Design and Research Institute, YRCC, Zhengzhou 4.0003. china beijing normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2%; when precipitation is steady, the average annual runoff will decrease by 2.4. if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2%. The mix regression model can well simulate annual runoff. (2) As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

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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, china 2. Graduate {4. of Chinese Academy of Sciences, {3. 10004., china 3. Sichuan Institute of Land Resource Management, Chengdu 61004., Sichuan , china 4. Department of resources and environment Science, Sichuan normal {4. , Chengdu 610061, Sichuan, china 5. {14. of Information Engineering, Chengdu {4. of Technology, Chengdu 610059, Sichuan, china 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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A Spatiotemporal Analysis of Urban Growth:A Case Study for Jinan Municipality,china

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Chinese Journal of Population,resources and environment 2006年第4期4卷 48-53页

作者： Yu Bohua1,2,3.Lu Changhe1,Zheng Xinqi 4.1.Institute of Geographical Sciences and Natural resources Research,Chinese Academy Sciences,beijing 100101,china 2.{3. of resources Science&Technolgy,beijing normal university,beijing 100875,china 3.Graduate School of the Chinese Academy of Science(GUCAS),beijing 10003.,china 4.Shandong normal university,Jinan,Shandong 250014.china Institute of Geographical Sciences and Natural resources Research Chinese Academy Sciences Beijing 100101 China college of resources Science & Technolgy Beijing Normal University Beijing 100875 China Graduate School of the Chinese Academy of Science(GUCAS) Beijing 100039China Institute of Geographical Sciences and Natural Resources Research Chinese Academy Sciences Beijing 100101 China Shandong Normal University Jinan Shandong 250014 China

china is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment, particularly in the costal *** study takes Jinan as a case presenting a time-series analysis of urban land expansion from 3.3.to *** results show that the urban expansion of Jinan city mainly took place in the last 100 years,especially after the economic reform in *** development and economic growth, urban population growth and migration policies were factors driving the urban land *** sprawl resulted in a disappearance of wetlands and a great loss of agricultural land,and over-pumping of ground water that led to disappearance of the city's feature, namely"the city of springs".

关键词： urban land expansion driving forces environmental effects Jinan

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Using remote sensing to research beijing wetlands dynamics

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Science china(Technological Sciences) 2006年第z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, ZHANG Songmei & LI Jing Key Lab of Resource environment and GIS of beijing, Capital normal {3., beijing 10003., china Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 13.012, china college of resources Science and Technology, beijing normal {3.,{14., china Capital normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital normal Univ GIS Beijing Beijing 100037 Peoples R China Chinese Acad Sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China beijing normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： beijing, wetland resource, remote sensing technology, ecological environment, dynamics.

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