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Regional differences and determinants of built-up area expansion in china

Science china Earth sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2,ZHU LiFen3,1 & DENG XiangZheng1,2 1 Center for chinese Agricultural Policy,chinese academy of sciences,beijing 100101,china 2 institute of geographic sciences and Natural resources research,chinese academy of sciences,beijing 100101,china 3 research Center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business University,Chongqing 400067,china 1. Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China 2. institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China 3. research Center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the chinese academy of sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in china from the late 1980s to 2000,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2000,although china's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, china

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Validity of the Bouchet's complementary relationship at 102 observatories across china

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Science china Earth sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2,ZHANG YongQiang3,LIU ChangMing1,2 1 institute of geographic sciences and Natural resources research,chinese academy of sciences,beijing 100101,china 2 Key Laboratory of Water Cycle and Related Land Surface Processes,chinese academy of sciences,beijing 100101,china 3 CSIRO Land and Water,PO Box 1666,Canberra ACT 2601,Australia institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing 100101 China CSIRO La

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102 observatories at different elevations across ***,the relationship is appropriate at the low elevations(<1000 m).With the increase of elevation,vapor transfer power becomes much less than radiation energy budget because of lower vapor pressure deficit and stronger global solar *** a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation china

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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2, MIAO Qilong1 & YU Qiang2 1. Department of Geography, Nanjing institute of Meteorology, Nanjing 210044, china 2. institute of geographic sciences and Natural resources research, chinese academy of sciences, beijing 100101, china Nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432 weather stations and 512 hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

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Accurate Quantification of Grassland Cover Density in an Alpine Meadow Soil Based on Remote Sensing and GPS

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Pedosphere 2005年第6期15卷 778-783页

作者： LIU Yan-Sui HU Ye-Cui PENG Liu-Ying institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 （China） Graduate School of chinese academy of sciences Beijing 100039 （China）

The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover densities to their image properties according to their geographic coordinates. The principles and procedures for quantifying grassland cover density from satellite image data were presented with an example from Qinghai Lake, china demonstrating how quantification could be made more accurate through the integrated use of remote sensing and global positioning systems (GPS). An empirical model was applied to an entire satellite image to convert pixel values into ground cover density. Satellite data based on 68 field samples was used to produce a map of ten cover densities. After calibration a strong linear regression relationship (r2 = 0.745) between pixel values on the satellite image and in situ measured grassland cover density was established with an 89% accuracy level. However, to minimize positional uncertainty of field samples, integrated use of hyperspatial satellite data and GPS could be utilized. This integration could reduce disparity in ground and space sampling intervals, and improve future quantification accuracy even more.

关键词： alpine meadow soil grassland cover density quantitative remote sensing Qinghai Lake

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A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2,3 & BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 330022, china 2 institute of geographic sciences and resources research, chinese academy of sciences, beijing 100101, china 3 School of Geography and Environmental sciences, Jiangxi Normal University, Nanchang 330022, china The Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China institute of geographic sciences and resources research Chinese Academy of Sciences Beijing China School of Geography and Environmental sciences Jiangxi Normal University Nanchang China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 31, 2005 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

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Effect of Sprinkler and Border Irrigation on Topsoil Structure in Winter Wheat Field

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Pedosphere 2010年第4期20卷 419-426页

作者： SUN Ze-Qiang KANG Yao-Hu JIANG Shu-Fang Soil and Fertilizer institute Shandong Academy of Agricultural Sciences Jinan 250100 (China) institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 (China)

A two-year experiment was carried out on the effect of sprinkler irrigation on the topsoil structure in a winter wheat field. A border-irrigated field was used as the control group. The total soil porosity, pore size distribution, pore shape distribution, soil cracks and soil compaction were measured. The sprinkler irrigation brought significant changes to the total soil porosity, capillary porosity, air-filled porosity and pore shape of topsoil layers in comparison with the border irrigation. The total porosity and air-filled porosity of the topsoil in the sprinkler irrigation were higher than those in the border irrigation. The changes in the air-filled and elongated pores were the main reasons for the changes in total porosity. The porosities of round and irregular pores in topsoil under sprinkler irrigation were lower than those under border irrigation. Sprinkler irrigation produced smaller soil cracks than border irrigation did, so sprinkler irrigation may restrain the development of macropore flow in comparison with border irrigation. The topsoil was looser under sprinkler irrigation than under border irrigation. According to the conditions of topsoil structure, it is preferable for crops to grow under sprinkler irrigation than under border irrigation.

关键词： macropore flow soil compaction soil crack soil pore shape soil porosity

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Effects of Temperature and Water Saturation on CO_2 Production and Nitrogen Mineralization in Alpine Wetland Soils

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Pedosphere 2009年第1期19卷 71-77页

作者： GAO Jun-Qin OUYANG Hua XU Xing-Liang ZHOU Cai-Ping ZHANG Feng beijing Forestry University Beijing 100083 （China） institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 （China） Graduate University of the chinese academy of sciences Beijing 100049 （China）

Relationships between carbon (C) production and nitrogen (N) mineralization were investigated in two alpine wetland soils of the Tibetan Plateau using laboratory incubation under different temperatures (5, 15, 25, and 35 ℃) and water saturation (noninundation and inundation). A significant positive relationship was found between CO2 production and N mineralization under increasing temperatures from 5 to 35 ℃ with the same water saturation condition in the marsh soil (r2 > 0.49, P 2 > 0.38, P 2), and a negative relationship with water saturation increasing at the same temperature, especially 25 and 35 ℃, in the marsh soil (r2 > 0.70, P 2 > 0.61, P 2 production and net N mineralization in the Tibetan alpine marsh and peat soils.

关键词： CO2 production N mineralization temperature water saturation wetland

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Spatiotemporal variations of vegetation cover on the chinese Loess Plateau(1981―2006):Impacts of climate changes and human activities

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Science china Earth sciences 2008年第1期51卷 67-78页

作者： XIN ZhongBao1,2, XU JiongXin1 & ZHENG Wei1, 2 1 institute of geographic sciences and Natural resources research, chinese academy of sciences, beijing 100101, china 2 Graduate University of the chinese academy of sciences, beijing 100049, china 1. institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of the chinese academy of sciences Beijing 100049 China

Spatiotemporal variations of chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981―1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990―1998; (3) vegetation cover declined rapidly during 1999―2001; and (4) vegetation cover increased rapidly during 2002―2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation construction has

关键词： Loess Plateau vegetation cover climate changes human activities GIMMS

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Rural Public Investment and Benefit in Sichuan's Hilly and Mountainous Areas

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Asian Agricultural research 2012年第8期4卷 28-32页

作者： ZHANG Hai-qin 1,3 ,LIU Shao-quan 1 ,LUO Ren-fu 2 ,ZHANG Lin-xiu 2 1. institute of Mountain Hazards and Environment,chinese academy of sciences,Chengdu 610041,china 2. institute of geographic sciences and Natural resources research,chinese academy of sciences,beijing 100101,china 3. Graduate University of chinese academy of sciences,beijing 100049,china

Using representative sampling survey data,we take the case of roads,domestic water,irrigation facilities,clinics and schools,to give an overview of the status quo of rural public investment in Sichuan's hilly and mountainous areas in the period 2005 -2008; conduct comprehensive analysis of public investment benefit,from the status quo of supply and demand,social benefit and villagers' satisfaction. The results show that the social benefit arising from the construction of road projects is good,while the social benefit arising from the construction of irrigation facilities is poor; the matching effect of supply and demand of public investment is poor,especially for the investment in irrigation facilities; on the whole,villagers' satisfaction with public investment has been promoted,but most of the villagers are still unsatisfied with the current irrigation facilities. The major capital source of rural public investment is from the government,but from the perspective of the villagers' demand,we should further increase the public financial input.

关键词： Rural public investment Social benefit index Evalu

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Fractionations of rare earth elements in plants and their conceptive model

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Science china(Life sciences) 2007年第1期50卷 47-55页

作者： DING ShiMing1,2, LIANG Tao2, YAN JunCai3, ZHANG ZiLi3, HUANG ZeChun2 & XIE YaNing4 1 Nanjing institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, china 2 institute of geographic sciences and Natural resources research, chinese academy of sciences, beijing 100101, china 3 Anhui Agricultural University, Hefei 230036, china 4 State Key Laboratory of Synchrotron Radiation, institute of High Energy Physics, chinese academy of sciences, beijing 100039, china 1. Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. institute of geographic sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China 3. Anhui Agricultural University Hefei 230036 China 4. State Key Laboratory of Synchrotron Radiation Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover, the tetrad effect was observed in these organs. Investigations into REE speciation in roots and in the xylem sap using X-ray absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations should be dominated by fixation mechanism in roots caused by cell wall absorption and phosphate precipitation, and by the combined effects of fixation mechanism and transport mechanism in aboveground parts caused by solution complexation by intrinsic organic ligands. A conceptive model was established for REE fractionations in plants based on the above studies.

关键词： rare earth elements (REEs) fractionation tetrad effect plant accumulation X-ray absorption spectroscopy (XAS) nanometer-sized TiO2

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