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An ecological hydraulic radius approach to estimate the instream ecological water requirement

Progress in natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( Key Laboratory of Water Cycle and Related Land Surface Process, institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing 100101, china Key Laboratory of Water and Sediment sciences, Ministry of Education & Water sciences College, beijing Normal University, beijing 100875, china Department of Hydraulic and Hydropower Engineering, North china Electric Power University, beijing 102206, china) [a]Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China [b]Key Laboratory of Water and Sediment sciences Ministry of Education & Water Sciences Gllege Beijing Noirnal University Beijing China [c]Departhent of Hydraulic and Hydropower Engineering North China Elecfric Power University Beijing China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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IMPACTS OF FLOOD EVENTS IN COARSE SEDIMENT-PRODUCING AREAS ON CHANNEL SILTATION AND FLUVIAL PROCESS OF THE LOWER YELLOW RIVER

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International Journal of Sediment research 2007年第2期22卷 142-149页

作者： Ou-yang ZHANG1, Xiufu FENG2 and Jiong-xin XU31 Bureau of Hydrology, Changjiang Water resources Commission, Hubei, Wuhan 430010, china2 Chengdu University of technology, Sichuan, Chengdu 610059, china3institute of Geographic sciences and natural resources research, cas, beijing 100101, china Changjiang Water resources Commiss Bureau Hydrol Wuhan 4310010 Peoples R China Chengdu Univ Technol Chengdu 610059 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

The method of multiple regression is used to analyze the influences of flood events from the coarse sediment producing areas on the channel siltation and fluvial process of the lower Yellow River based on the flood events from 1950 to 1985. The results showed that the flood events from the coarse sediment producing areas carry larger amounts of sediment load and coarser particle sizes than from other source areas, which increases deposition in the lower river channel. And there exist good correlations between channel siltation of the lower reaches of the Yellow River and the coming water and sediment of flood events from the coarse sediment producing areas. Through these correlations, the amounts of sediment deposition in the lower river channel could be roughly estimated based on the runoff and sediment load of flood events from the coarse sediment producing areas. The sediment deposition caused the fluvial process. There exists a complex response of channel form change to the coming water and sediment load of flood events from the coarse sediment producing areas. When the sediment concentration is smaller than 200kg/m3, the ratio between wide-depth ratio after flood and wide-depth ratio before flood((B/h)a / (B/h)b) will increase with the increase of the maximum sediment concentration; when the sediment concentration is near 200kg/m3, (B/h)a / (B/h)b reaches the maximum value; and when the sediment concentration reaches the limits of hyperconcentrated flow, (B/h)a / (B/h)b will decrease with the increase of the maximum sediment concentration. Generally, flood events from the coarse sediment producing areas made channel form of the lower Yellow River deeper and narrower, but a large amount of sediment deposition simultaneously occurs. So, the impacts of flood events from the coarse sediment producing areas on the channel of the lower Yellow River are lessened.

关键词： Channel siltation Fluvial process Coarse sediment-producing areas Flood events Yellow River basin

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The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, research Center for Eco-Environmental sciences, Chinese Academy of sciences, beijing 100085, china institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, china Department of Forestry and natural resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of Chinese Academy of sciences, beijing 100101, china 1. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

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Spatial patterns of urban land use growth in beijing

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Journal of geographical sciences 2002年第3期12卷 266-274页

作者： LIU Shenghe, Sylvia Prielei, LI Xiubin(1. Inst. of Geographic sciences and natural resources research, cas, beijing 100101, china 2. International institute for Applied System Analysis, A-2361 Laxenburg, Austria) Inst. of Geographic sciences and natural resources research. cas 北京 100101 International institute for Applied System Analysis A-2361 Laxenburg 奥地利

By using digitized land use maps of beijing in 1982, 1992 and 1997 and employing GIS spatial analysis techniques, this paper conducts an empirical study on the spatial differentiation and spatial patterns of urban land use growth in beijing in the period of 1982–1997. It is observed that urban land use growth in beijing went beyond the control of urban planning, in terms of the extraordinary high growth rate and undesired spatial pattern. The rate of urban expansion after 1982, which was predominated by growth of industrial land, was extraordinary high compared to its historical period. While its growth centers have been actively shifting toward the northern part, rather than toward the southern and eastern parts as designated by the latest General Plan (1991–2010) of beijing, its spatial pattern of urban land use growth in general was in distinct concentric sprawl, which seriously violated the General Plan of beijing.

关键词： urban land use spatial differentiation growth pattern GIS beijing

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Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in china

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Journal of geographical sciences 2002年第4期12卷 397-404页

作者： DENG Xiangzheng, LIU Jiyuan, ZHUANG Dafang, ZHAN Jinyan, ZHAO Tao(Inst. of Geographic sciences and natural resources research, cas, beijing 100101, china) Inst. of Geographic sciences and natural resources research CAS 北京 100101

This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern china. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.

关键词： land use driving force interlock area of farming and pasturing china

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Oxygen and hydrogen isotopic compositions of coexistent minerals of the Tasigake alkali granite pluton,northern Xinjiang:constraints upon the cause of ^(18)O-D depletion and the ^(18)O/^(16)O exchange kinetics

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Chinese Science Bulletin 1999年第12期44卷 1086-1093页

作者： LIU Wei, ZHAO Zhenhua ZHANG Fuqin research Center of Mineral resources Exploration, institute of Geophysics , Chinese Academy of sciences , beijing 100101, china Guangzhou institute of Geochemistry, Chinese Academy of sciences , Guangzhou 510640, china research Center of Mineral Resource Exploration Institute of Geophysics Chinese Academy of Science Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Oxygen and hydrogen isotopic compositions have been determined of three coexistent mineral triplets of alkali feldspar, quartz, arfvedsonite of 11 samples collected from the Tasigake alkali granite pluton, Ulungur River region, northern Xinjiang. Isotopic exchange with meteoric water during subsolidus cooling caused strong 18O-D depletion and the remarkable nonequilibrium 18O/16O relation between coexistent minerals. 18O/16O exchange kinetic effects of the three minerals are simultaneously and consistently modelled. Exsolution and microtextural reorganization of alkali feldspar, and infiltration of water have been mutually facilitated by each other. Shallow intrusion, and circulation of meteoric water throughout the pluton cool it effectively. As a result, the "heat engine" is rapidly extinguished, and the nonequilibrium 18O/16O relation is frosen.

关键词： 18O-D depletion isotopic exchange kinetics alkali granite Ulungur.

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Introduction to the Special Issue on Eco-compensation in china

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Journal of resources and Ecology 2015年第6期6卷 353-354页

作者： XIE Gaodi institute of Geographic sciences and natural resources research, cas Professor of institute of Geographic sciences and natural resources research CAS Email: xiegd@igsnrr.ac.cnAddress:11-A Datun Road Anwai Chaoyang District Beijing 100101 China

Owing to emphasis on economic growth since 1978 the ecological and environmental problems are continuously emerging in china especially in the river source areas and ecological fragile areas of china and thus,these areas have to face the conflict between economic development and environmental *** a result,it is an urgent need to establish a scientific and reasonable ecological compensation mechanism to coordinate the contradiction.

关键词：生态补偿机制生态环境问题生态脆弱地区经济增长环境保护经济发展科学合理河流

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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 sciences 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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Dynamic change of net primary productivity and fractional vegetation cover in the Yellow River Basin using multi-temporal AVHRR NDVI Data

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Journal of geographical sciences 2002年第1期12卷 29-34页

作者： SUN Rui1, LIU Chang-ming2, ZHU Qi-jiang1 (1. Department of Geography, beijing Normal University, beijing 100875, china 2. institute of Geographic sciences and natural resources research, cas, beijing 100101, china) Department of Geography Beijing Normal University 北京 100875 institute of Geographic sciences and natural resources research CAS 北京 100101

An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1982 to 1999 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.

关键词： net primary productivity fractional vegetation cover rainfall remote sensing

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Spatial Organization Mechanism of Aircraft Manufacturing

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Chinese Journal of Population,resources and Environment 2010年第1期8卷 62-70页

作者： Dong Yan1,2,Chu Bo1,3 1.institute of Geographic sciences and natural resources research,cas,beijing 100101,china 2.Graduate University of Chinese Academy of sciences,beijing 100049,china 3.Fujian Provincial Department of Foreign Trade and Economic Cooperation,Fuzhou Fujian 350003,china institute of Geographic sciences and natural resources research CAS Beijing 100101 China Graduate University of Chinese Academy of sciences Beijing 100049 China Fujian Provincial Department of Foreign Trade and Economic Cooperation Fuzhou Fujian 350003 China

Unquestionably,aircraft industry plays an important part in both economy and security of a ***,few of articles have dealt with the spatial development of this industry *** purpose of this article is to analyze the dynamics of agglomeration and diffusion of aircraft *** a historical view,with some spatial analysis methods,this research discusses the characteristics and patterns of aircraft industry's spatial organization and evolution,globally,nationally and regionally *** find out there is a ‘Matthew effect' in aircraft industry of the world,and the spatial evolution of the industry is consistent with the nation's industrialization ***,it concludes that the main agglomeration forces consist of capital,talents,technology and cluster's advantages,and the main diffusion forces include comparative advantages,cost and risk sharing,emerging markets,development policy for backward regions and military *** the factors can be divided into market forces making the spatial development of aircraft industry normal and non-market forces making that *** particular,lessons from the USA and France are expected to be conducive to the rise of china's aircraft industry in the future.

关键词： aircraft manufacturing diffusion agglomeration spatial evolution

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