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spatial heterogeneity of the driving forces of cropland change in china

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science china Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2,3 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 Arts and sciences of beijing Union University, beijing 100083, china 4. school of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL36849, UsA institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing China Graduate school of the chinese academy of sciences Beijing China school of Forestry and Wildlife sciences Auburn University Auburn Alabama USA College of Arts and sciences of beijing Union University Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIs combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

Ecological hydraulic radius model to calculate instream flow requirements for transporting sediment in the western water transfer region

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science china(Technological sciences) 2009年第11期52卷 3401-3405页

作者： MEN BaoHui1 & LIU ChangMing2 1 Renewable Energy institute, North china Electric Power University, beijing 102206, china 2 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 Renewable Energy institute North China Electric Power University Beijing China Key Laboratory of Water Cycle and Related Land surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Transporting sediment is a natural function of the river. To maintain the normal evolution of the river certain amount of water flow is required, which is called the instream flow requirements for transporting sediment (IFRTs). We defined the permitting flow velocity by the conception of IFRTs, and also put forward the ecological hydraulic radius model (EHRM) to estimate IFRTs. The calculating process of EHRM is explained by the example of Daofu Hydrological station on Xianshui branch of Yalong River in the west line first-stage construction of south-North Water Transfer Project. The result shows that the IFRTs occupied 29.7%―59.5% of annual mean discharge in flood season, the average of IFRTs was about 100.2 m3/s during 1966―1987, it is close to the IFRTs 90 m3/s calculated by IFRTs conception. Hence, it is feasible to use EHRM to calculate IFRTs.

关键词： ecological hydraulic radius model (EHRM) instream flow requirements for transporting sediment (IFRTs) permitting flow velocity ecological hydraulic radius for transporting sediment

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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science china(Technological sciences) 2004年第Z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2 2 & ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land surface Processes, institute of geographic science and natural resources research, chinese academy of sciences, beijing 100101, china 2. institute of Environmental science, beijing Normal University, beijing 100875, china 3. Water resources Conservation Committee of Yellow River, Zhengzhou 450003, china Key Laboratory of Water Cyde & Related Land surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences Beijing China institute of Environmental science Beijing Normal University Beijing China Water resources Conservation Committee of Yellow River Zhengzhou China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIs/Rs. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIs and Rs, Jinghe Basin, Yellow River Basin.

Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in natural science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI shuhe, WANG Tianduo, sUN Xiaomin and ZHANG Renhua ( chinese academy of Meteorological science, beijing 100081, china institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, shanghai 200032, china) chinese academy of Meteorological science Beijing 100081 China institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China Mathematics Department Ocean University of China Qingdao 266071 China shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at Yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china Plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

sEDIMENT YIELD MODELING FOR sINGLE sTORM EVENTs BAsED ON HEAVY-DIsCHARGE sTAGE CHARACTERIZED BY sTABLE sEDIMENT CONCENTRATION

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International Journal of sediment research 2007年第3期22卷 208-217页

作者： Mingguo ZHENG1, Qiangguo CAI2, and Qinjuan CHENG3 1Assistant professor, Key Laboratory of Water Cycle and Related Land surface Processes, institute of geographic sciences & natural resources research, CAs, beijing 100101,china. 2 Professor, Key Laboratory of Water Cycle and Related Land surface Processes, institute of geographic sciences & natural resources research, CAs, beijing 100101,china. 3 Doctoral candidate, Key Laboratory of Water Cycle and Related Land surface Processes, institute of geographic sciences & natural resources research, CAs, beijing 100101,china. Graduate school of the chinese academy of sciences, beijing 100039, china. chinese Acad sci Inst Geog Sci & Nat Resources Res Key Lab Water Cycle & Related Land Surface Proc Beijing 100101 Peoples R China

The relation between runoff volume and sediment yield for individual events in a given watershed receives little attention compared to the relation between water discharge and sediment yield, though it may underlie the event-based sediment-yield model for large-size watershed. The data observed at 12 experimental subwatersheds in the Dalihe river watershed in hilly areas of Loess Plateau, North china, was selected to develop and validate the relation. The peak flow is often considered as an important factor affecting event sediment yield. However, in the study areas, sediment concentration remains relatively constant when water discharge exceeds a certain critical value, implying that the heavier flow is not accompanied with the higher sediment transport capacity. Hence, only the runoff volume factor was considered in the sediment-yield model. As both the total sediment and runoff discharge were largely produced during the heavy-discharge stage, and the sediment concentration was negligibly variable during this stage, a proportional function can be used to model the relation between event runoff volume and sediment yield for a given subwatershed. The applicability of this model at larger spatial scales was also discussed, and it was found that for the Yaoxinzhuang station at the Puhe River basin, which controls a drainage area of 2264km2, a directly proportional relation between event runoff volume and sediment yield may also exist.

关键词： sediment yield Peak flow Flow-sediment relation Loess Plateau

Aridity/humidity status of land surface in china during the last three decades

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science china Earth sciences 2005年第9期48卷 1510-1518页

作者： WU shaohong1, YIN Yunhe1,2, ZHENG Du1 & YANG Qinye1 1. institute of geographical sciences and natural resources research, chinese academy of sciences (CAs), beijing 100101, china 2. Graduate school of the CAs, beijing 100039, china institute of geographical sciences and natural resources research Chinese Academy of Sciences (CAS) Beijing China Graduate school of the CAs Beijing China

To clarify aridity/humidity status of land surface is helpful for studying environmental background and regional differences, seeking causes of environmental change, and providing a scientific basis for researches on climate change in the future. In this paper, the authors calcu- lated potential evapotranspiration of china using data from 616 meteorological stations during the period of 1971―2000 with the Penman-Monteith model recommanded by FAO in 1998. Vy- sothkii’s model was used to calculate aridity/humidity index. Then the calculated results of sta- tions were interpolated to land surface using ArcGIs. Results show that the annual average po- tential evapotranspiration is 400―1500 mm in the whole country, 600―800 mm in most parts of it; and 350―1400 mm in growing season (April―Octobor), which is nearly 200 mm less than the annual average. According to the aridity/humidity indexes of 1.0, 1.5 and 4.0, the aridity/humidity status is categorized to four types, namely, humid, subhumid, semiarid and arid. A majority of stations (76%) are more humid in growing season than the annual average. Results of com- prisons between the distribution map of aridity/humidity index with that of precipitation and vegetation indicate a good consistence of aridity/humidity status with natural environment. Therefore potential evapotranspiration calculated with modified FAO’s Penman-Monteith model in combination with aridity/humidity index that considers water balance can more reasonably explain the actual land surface aridity/humidity status of china.

关键词： potential evapotranspiration, aridity/humidity status, land surface, regional differences, Penman-Monteith.

Delineation of boundary between tropical/subtropical in the middle section for eco-geographic system of south china

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Journal of geographical sciences 2001年第1期11卷 80-86页

作者： WU shao-hong, ZHENG Du (institute of geographic sciences and natural resources research, CAs, beijing 100101, china) institute of geographic sciences and natural resources research CAS Beijing China

This paper discusses division on tropical/subtropical boundary of middle section in south china. This discussion results in new understanding on eco-geographic regions and their boundaries, especially on gradual changes of natural conditions between eco-geographic regions. It analyzes results of the same area by other researchers, clarifies differences and causes of the differences for the results. Boundaries of eco-geographic regions cannot be drawn as a line as changes from tropical to subtropical are gradual. Therefore, for an eco-geographic region like tropical zone, definite boundaries must be mapped while gradual changes are considered. Temperature, vegetation and soil are the indexes to divide tropical and subtropical. After indexes of tropical zone are confirmed, data of annual average index reflect general state of the tropical zone. Line from such data is called “tropical boundary”. On the other hand, affected by the monsoon climate, some years are hotter and some are cooler. In hotter years, temperature of north area of tropical boundary reaches tropical state whereas in cooler years, such area moves southward. Boundary of the hottest year is called annual tropical line and that of the coolest year true tropical line. Temperatures in areas south to annual tropical line can probably reach tropical in some years. Temperatures in areas south to real tropical line reach tropical every year. The area from true tropical to annual tropical is called tropical fluctuating zone. Therefore, new concepts of tropical, annual tropical, true tropical and tropical fluctuating zone are formed to understand tropical area from a new point of view in the paper. Based on the indexes of climate, vegetation and soil, boundaries of tropical, annual tropical, true tropical and tropical fluctuating zone of the study area are established. The tropical fluctuating zone explains different locating of different researchers. The paper also puts forward a new method to display boundary

关键词： eco-geographic region tropical annual tropical true tropical tropical fluctuating zone

Analysis and Modeling on the spatial structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3, Zhang Zulu2, Jiang Luguang 1 1. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 2. College of Population, resources and Environment, shandong Normal University, Jinan shandong 250014, china 3. Graduate school of the chinese academy of sciences, beijing 100039, china institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China Graduate school of the chinese academy of sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004, the spatial structure of Jinan is studied in this paper with the method of geographic Information system (GIs). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

structural patterns of land types and optimal allocation of land use in Qinling Mountains

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Journal of geographical sciences 2001年第1期11卷 99-109页

作者： LIU Yan-sui, DENG Xiang-zheng (institute of geographic sciences and natural resources research, CAs, beijing 100101, china) institute of geographic sciences and natural resources research CAS Beijing China

The case study based on Qinling Mountains in shaanxi Province of china, in virtue of the information from TM image, classifies the land types and analyzes their spatial and temporal differential law, and puts forward three structural patterns of land types in mountainous areas, namely, spatial, quantitative and qualitative structures of mountainous land types. Furthermore, it has been noticed that the analysis of structural patterns can disclose the heterogeneity and orderliness of combination of land types, which can lay the theoretic foundation for comprehensively recognizing ecological characteristics and succession law of structure and function of land types. After the all-around comparative analysis, an optimal allocation of land use in Qinling Mountains has been put forward according to the principle of sustainable development and landscape ecology, which can lay the scientific foundation in practice for the structural adjustment and distribution optimization from the macro level to micro level.

关键词： land types succession of land types structural patterns optimal allocation Qinling Mountains