Based on the theory of information entropy, time series and spatial variation of land use changes of Bijie City in 2009-2013 were analyzed from different dimensions such as land use degree and land use diversity. The ...Based on the theory of information entropy, time series and spatial variation of land use changes of Bijie City in 2009-2013 were analyzed from different dimensions such as land use degree and land use diversity. The result showed that in 2009-2013, the forest vegetation was well protected, and the construction land was under reasonable expansion under the influence of economic development, the land use degree of which developed gradually to width and depth, and the trend of information entropy showed a graduate increase, indicating that land use scale became more reasonable and the area of different land type became more balanced in Bijie in the period. The study results showed that land resources in Bijie City were used rationally under the strategy from central government local government,and Bijie was in the benign development of economic development—resource distribution—scale change. Moreover, Bijie chould further improve land use pattern such as redevelop stock construction land, optimize the industrial land use pattern and mountain agricultural land development in the future.展开更多
This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO 2 emission performance.With the index,the authors have measured ...This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO 2 emission performance.With the index,the authors have measured the CO 2 emission performance of 28 provinces and autonomous regions in China from 1996 to 2007;with the convergence theory and panel data regression model,the authors analyze the regional differences and the influencing factors.It is found that the performance of CO 2 emissions in China has been continuously improved mainly due to the technological progress,and the average improvement rate is 3.25%,with a cumulative improvement rate of 40.86%.In addition,the CO 2 emission performance varies across four regions.As a whole,the performance score of eastern China is the highest.The northeastern and central China has relatively lower performance scores,and the western China is relatively backward.The regional differences are decreasing,and the performance of CO 2 emissions is convergent.The influence of some factors on the performance of CO 2 emissions is significant,such as the level of economic development,the level of industrial structure,energy intensity,and ownership structure.The influence of some factors,such as opening-up to the outside world,on the performance of CO 2 emissions is not significant..展开更多
The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matc...The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matching and other methods. The authors also construct a research hot regions extraction model of grassland deterioration in China based on a comprehensive research hot regions index of toponyms and then analyze the spatial pattern and dynamic change in research hot regions of grassland deterioration in China. The research shows the following：（1） The spatial heterogeneity of grassland deterioration in China can be effectively described by a model of grassland deterioration based on the comprehensive research hot regions index.（2） The research hot regions of grassland deterioration are mainly distributed in most regions of Inner Mongolia, Xinjiang, Qinghai, Tibet, Gansu and other provinces. The northeastern region of Inner Mongolia（such as Hulunbeier） and the eastern region of Inner Mongolia（such as Xilin Gol, Chifeng and Wulanchabu） are significant hot regions in the study of grassland deterioration.（3） The number of high research hot regions increases from 81 in the 1950 s to 99 in the 2000s; the area increases from 1.038 million km2 to 1.146 million km2. The degree of hot for grassland deterioration research in 197 counties showed an upward trend. This paper also discusses the relationship between the region of research hot regions and the region of grassland deterioration and then indicates the differences between them in time matching, space matching and concept matching.展开更多
基金Supported by the Mutual Fund Project for Soft Science Research of Guizhou Science and Technology Department and Guizhou University of Finance and Economics(Qiankehe LH[2013]7249)~~
文摘Based on the theory of information entropy, time series and spatial variation of land use changes of Bijie City in 2009-2013 were analyzed from different dimensions such as land use degree and land use diversity. The result showed that in 2009-2013, the forest vegetation was well protected, and the construction land was under reasonable expansion under the influence of economic development, the land use degree of which developed gradually to width and depth, and the trend of information entropy showed a graduate increase, indicating that land use scale became more reasonable and the area of different land type became more balanced in Bijie in the period. The study results showed that land resources in Bijie City were used rationally under the strategy from central government local government,and Bijie was in the benign development of economic development—resource distribution—scale change. Moreover, Bijie chould further improve land use pattern such as redevelop stock construction land, optimize the industrial land use pattern and mountain agricultural land development in the future.
基金financial support provided by the National Social Science Foundation of China (Grant No. 08 &ZD046)National Natural Science Foundation of China (Grant No.70903031 and 41071348)
文摘This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO 2 emission performance.With the index,the authors have measured the CO 2 emission performance of 28 provinces and autonomous regions in China from 1996 to 2007;with the convergence theory and panel data regression model,the authors analyze the regional differences and the influencing factors.It is found that the performance of CO 2 emissions in China has been continuously improved mainly due to the technological progress,and the average improvement rate is 3.25%,with a cumulative improvement rate of 40.86%.In addition,the CO 2 emission performance varies across four regions.As a whole,the performance score of eastern China is the highest.The northeastern and central China has relatively lower performance scores,and the western China is relatively backward.The regional differences are decreasing,and the performance of CO 2 emissions is convergent.The influence of some factors on the performance of CO 2 emissions is significant,such as the level of economic development,the level of industrial structure,energy intensity,and ownership structure.The influence of some factors,such as opening-up to the outside world,on the performance of CO 2 emissions is not significant..
基金National Key Research and Development Plan Program(2016YFC0503701,2016YFB0501502)Key Project of High Resolution Earth Observation System(00-Y30B14-9001-14/16)
文摘The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matching and other methods. The authors also construct a research hot regions extraction model of grassland deterioration in China based on a comprehensive research hot regions index of toponyms and then analyze the spatial pattern and dynamic change in research hot regions of grassland deterioration in China. The research shows the following：（1） The spatial heterogeneity of grassland deterioration in China can be effectively described by a model of grassland deterioration based on the comprehensive research hot regions index.（2） The research hot regions of grassland deterioration are mainly distributed in most regions of Inner Mongolia, Xinjiang, Qinghai, Tibet, Gansu and other provinces. The northeastern region of Inner Mongolia（such as Hulunbeier） and the eastern region of Inner Mongolia（such as Xilin Gol, Chifeng and Wulanchabu） are significant hot regions in the study of grassland deterioration.（3） The number of high research hot regions increases from 81 in the 1950 s to 99 in the 2000s; the area increases from 1.038 million km2 to 1.146 million km2. The degree of hot for grassland deterioration research in 197 counties showed an upward trend. This paper also discusses the relationship between the region of research hot regions and the region of grassland deterioration and then indicates the differences between them in time matching, space matching and concept matching.
