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agricultural sciences in china 2010年第12期9卷 1807-1815页

作者： WANG Ya-jing, BI Yu-yun and GAO Chun-yu institute of agricultural resources and regional planning, chinese academy of agricultural sciences, beijing 100081, P.R.china institute of agricultural resources and regional planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

The study was undertaken to evaluate the collectable and usable volume of existing straw resources, its suitability for different ways of utilization and fully reorganization of its development potential in china. Based on the results on the stubble heights of major crops in the huang-Huai-Hai area （the area along the Yellow River, Huai River, and Hai River）, the evaluation of the collectable and usable coefficients, and the collectable and usable volumes of various straw resources in china were worked out during 2005. The respective collectable and usable volumes of straw resources were worked out on the basis of suitability as fuel, feed, fertilizer, and base material for edible mushrooms. The total collectable and utilizable quantity of straw in china was 685 950 000 t, and the mean collection coefficient was 0.81 during 2005. The quantity of straw residue and wasted straw accounted for 19%. The collectable and utilizable quantities of grain, cash crop, and other crop straw were 492 310 000, 162 610 000, and 31 030 000 t which accounted for 71.77, 23.71, and 4.52%, respectively of the total collectable and utilizable quantity of straw. The quantity of straw which could be used as fuel was 635 000 000 t, which accounted for 92.63% of total quantity of the straw in the country during 2005. Among the total quantity of collectable and utilizable straw in china during 2005, the quantities of straw suitable and unsuitable for being processed as feedstuff were 587 640 000 and 98 310 000 t, which accounted for 85.67 and 14.33%, respectively. The quantity of straw residue returned to the field and collectable and utilizable straw for direct field restoration was 616 000 000 t, which accounted for about three-fourths of the total straw yield, while the quantity of straw for cultivation of edible mushrooms and industrial processing was about 587 000 000 t, which accounted for more than 85% of the total collectable and utilizable straw. The evaluation results indicate that t

关键词： china straw resources collectable and utilizable quantity suitability assessment

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

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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 Center for chinese agricultural Policy Chinese Academy of Sciences Beijing China institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing China Research Center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 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

Response of Rice Varieties to Bound Residues of Metsulfuron-Methyl in a Paddy Soil

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Pedosphere 2007年第4期17卷 487-492页

作者： LI Zhao-Jun WANG Hai-Zhen xu Jian-Ming WU Jian-Jun MA Guo-Rui institute of Soil and Water resources and Environmental Science Zhejiang University Hangzhou 310029 （China）. institute of agricultural resources and regional planning Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling Chinese Academy of Agricultural Sciences Beijing 100081 （China）

Metsulfuron-methyl is one of the widely used sulfonylurea herbicides. However, approximately half of the applied metsulfuron-methyl may remain as bound residues in soil. To characterize the response of rice plants to residual metsulfuron-methyl in soil, the activities of acetolactate synthase （ALS）, superoxide dismutase （SOD）, peroxidase （POD）, and catalase （CAT） were investigated in two rice varieties that differed in susceptibility to the herbicide. Changes in the activity of these enzymes in leaves and roots of Xiushui 63, a sensitive rice variety, were greater than those in a resistant variety Zhenong 952. Irrespective of variety, changes in the enzyme activity were greater in the roots than in the leaves. The activities of ALS and CAT decreased, while the SOD activity increased with the increase in the amounts of bound residues of metsulfuron-methyl （BRM） in soil. The POD activity increased at the BRM level of 0.025 mg kg^-1, but decreased at the BRM level of 0.05 mg kg^-1. The results showed that the bound residues of sulfonylurea herbicides may affect metabolism of rice plants.

关键词： ALS activity bound residues CAT activity metsulfuron-methyl SOD activity

Spatial-Temporal Changes in Grain Production, Consumption and Driving Mechanism in china

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Journal of Integrative Agriculture 2013年第2期12卷 374-385页

作者： xu Shi-wei WU Jian-zhai SONG Wei LI Zhi-qiang LI Zhe-min KONG Fan-tao Key Laboratory of Digital agricultural Early-Warning Technology Ministry of Agriculture/Agriculture Information Institute Chinese Academy of Agriculture Sciences institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences

The spatial-temporal patterns of grain production and consumption have an important influence on the effective national grain supply on condition of tight balance in the total grain amount in china. In this paper, we analyze the spatial-temporal pattems of grain production, consumption and the driving mechanism for their evolution processes in china. The results indicate that both gravity centers of grain production and consumption in china moved toward the northern and eastern regions, almost in the same direction. The coordination of grain production and consumption increased slightly from 1995 to 2007 but decreased from 2000 to 2007. There is a spatial difference between the major districts of output increase and the strong growth potential in grain consumption, which indicates an increasing difficulty in improving the regional coordination of grain production and consumption. The movement of the gravity center of grain production is significantly correlated with regional differences in grain production policy, different economic development models, and spatial disparity of land and water resource use. For grain consumption, the main driving factors include rapid urbanization, the upgrade of food consumption structure, and distribution of food industries.

关键词： grain production grain consumption gravity center driving mechanism

Crop Yield and Soil Responses to Long-Term Fertilization on a Red Soil in Southern china

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Pedosphere 2009年第2期19卷 199-207页

作者： ZHANG Hui-Min WANG Bo-Ren xu Ming-Gang FAN Ting-Lu Key Laboratory of Plant Nutrition and Nutrient Cycling Ministry of Agriculture of China and Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Resource and Environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China Department of Agronomy Henan University of Science and Technology Luoyang 471003 China

A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M)was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,china. Average grain yields of wheat and corn(1 672 and 5 111 kg ha-1,respectively)for the treatment NPKM were significantly higher than those(405 and 310 kg ha-1)of the unfertilized control and single inorganic fertilizer *** with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 35 to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year?1,except for the treatments PK and *** long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+and available Cu2+and Zn2+contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer *** to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil *** improved grain yields of wheat and corn, suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil.

关键词： corn long-term fertilization red soil wheat yield

A Methodology Framework for regional Land-use Change Studies based on Landsat TM images: A Case Study in Northeast china

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chinese Journal of Population,resources and Environment 2004年第4期2卷 3-11页

作者： Deng Xiangzheng , huang Shumin , Zhan Jinyan & Zhao Tao Center for chinese agricultural Policy, chinese academy of sciences, beijing 100101 institute of Geographical sciences and Natural resources Research, chinese academy of sciences, beijing 100101 Anthropology Department, Iowa State University, Ames, Iowa 50010-1050, USA, Center for chinese agricultural Policy Chinese Academy of Sciences Beijing 100101 China institute of Geographical sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China Anthropology Department Iowa State University Ames IA 50010-1050 United States

Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. This paper analyzed the land-use change in Northeast china during 1985-2000 based on Landsat TM images. It divides Northeast china into five land-use zones based on the dynamic degree model of land-use: woodland/grassland-arable land conversion zone, dry land-paddy field conversion zone; urban expansion zone, interlocked zone of farming and pasturing and reclamation and abandon zone. The findings include the obvious increase of cropland area, paddy field and dry land increased by 75 and 276 thousand hm2 respectively; urban areas expanded rapidly, areas of town and rural residence increased by 76.8 thousand hm2; areas of forests and grassland decreased sharply with the amounts of 1399 and 1521 thousand hm2 respectively; areas of water body and unused land increased by 148 and 514 thousand hm2 respectively. This paper also discusses the

关键词： spatial pattern land use land-use change driving force Northeast china

Simulation and Prediction of Soil Organic Carbon Dynamics in Jiangsu Province Based on Model and GIS Techniques

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Journal of Integrative Agriculture 2003年第9期 67-73页

作者： SHEN Yu 1, huang Yao 1,2 , ZONG Liang gang 1, ZHANG Wen 1, xu Mao 3 and LIU Lin wang 3 ( 1College of resources and Environmental sciences, Nanjing agricultural University, Nanjing 210095, P.R.china 2institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, P.R.china 3Jiangsu agricultural and Forestry Department, Nanjing 210036, P.R.china)

Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbon model with a linkage of GIS. Four data sets of soil organic carbon measured from various field experiments in Jiangsu Province were used to validate the model. It was demonstrated that the model simulation in general agreed with the field measurements. Model simulation indicated that the SOC content in approximately 77% of the agricultural soils in Jiangsu Province has increased since the Second National Soil Survey completed in the early 1980s. Compared with the values in 1985, the SOC content in 2000 was estimated to increase by 1.03.0 g kg 1 for the north and the coastal areas of the province, and by 3.55.0 g kg 1 for the region of Tai Lake in the south. A slight decrease (about 0.51.5 g kg 1 ) was estimated for the central region of Jiangsu Province and the Nanjing Zhenjiang hilly area. Model prediction for 2010 A.D. under two scena rios, i.e., with 30 and 50% of the harvested crop straw incorporation, suggested that the SOC in Jiangsu Province would increase, and thus that the agricultural soils would have potential as organic carbon storage. The incorporation of crop straw into soils is of great benefit to increase soil carbon storage, consequently to benefit the control of the rise of atmospheric CO 2 concentration and to maintain the sustainable development of agriculture.

关键词： Soil Organic carbon Model GIS Jiangsu Province

On Fractal Characteristic of Grassland in Northern Agro-grazing Ecotone of china

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On Fractal Characteristic of Grassland in Northern Agro-graz...

Spatial distribution regularity and influence factors of population density in the LRGR

第三世界生态高峰会

作者： Yang X.C. xu B. Tao W.G.institute of agricultural resources and regional planning,The chinese academy of Agrieultural sciences,beijing 100081,china 2.The chinese academy of Land resources and Economy,beijing 101149,china

Grassland is not only one of the important ecosystems,but also is the basic vegetation for northern agro-grazing ecotone of *** the past decades,human activities have caused great land cover changes, such as desertification,grassland degradation,and *** and timely understanding of grassland is of critical importance for protecting northern agro-grazing ecotone's grassland *** fractal characteristic of grassland was analyzed using fractal theory in northern agro-grazing ecotone of *** significant conclusions are drawn as follow:(1) Spatial fractal characteristic is objectively exist in different steppe types or different elevation belt or grassland above some elevation;(2) The spatial structure of Temperate desert is the most complicated and the most unstable and that of Apline meadow is the simplest and the steadiest of all the steppe types.(3) In different elevation belt,spatial structure of High mountain grassland is the most complicated and the steadiest,and that of Middle plain is the simplest, and that of Low plain is the most unstable.(4) Spatial structure above some elevation is exist from complicated to simple and from steady to unstable when elevation is changing from high to *** above conclusions are very important for grassland administration and decision-making in northern agro-grazing ecotone of china.

关键词： Northern agro-grazing ecotone grassland Spatial structure Characteristic

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Science Bulletin 2007年第S2期 90-97页

作者： SONG GuoBao~(1,2) LI ZhengHai~(1,3+) BAO YaJing~1 L HaiYan~4 GAO JiXi~3 WANG HaiMei~5 xu Tian~6 CHENG Yan~7 1 institute of Bio-resources and Environment,College of Life Science,Dalian Nationalities University,Dalian 116600,china 2 College of resources Science & Technology,beijing Normal University,beijing 100875,china 3 Innovation Base of regional Ecology,chinese Research academy of Environmental sciences,beijing 100012,china 4 institute of agricultural resources and regional planning,chinese academy of agricultural sciences,beijing 100081,china 5 Inner Mongolia Municipality Observatory,Huhhot 010051,china 6 College of Life Science,Inner Mongolia University,Huhhot 010021,china 7 College of Ecological Environment,Inner Mongolia agricultural University,Huhhot 010018,china

Combining GIS measures and statistic methods,this paper selects the physiographic factors and climatic factors to study the influencing strength and its functional forms of all factors on population density in the *** addition,this paper simulates the status of population density distribution in the LRGR with the factors influencing the population density *** findings indicate the following circumstances:(1)All natural factors have influence on the spatial pattern of population density in the LRGR,but the influencing extent and forms are quite *** factors and traffic network density have great influence on population density,while such factors as temperature and precipitation have little influence on population *** relationship between the popula- tion density and the altitude and traffic network density assumes the negative and positive linear cor- relation trends,while the influence of water system density and slope appears to be the exponential function and logarithmic function separately.(2)The population is scattered throughout LRGR and takes on such features as integral scattering and local concentration because of the influence of natural ***,a high population density belt has been formed in the middle of LRGR,and a high population density patch comes into being in the south of LRGR.(3)There is a good linear re- gression relationship between population density and human activity index(HAI)in the LRGR,which reflects that population density can present the artificial disturbance on natural ecosystem in the LRGR. (4)The increase of population density leads to the decrease of NDVI index.

关键词： population density artificial disturbance vegetation coverage physiographic factor LRGR