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1.
苏浩  吴次芳 《经济地理》2023,(6):166-175
诊断耕地系统健康状态,揭示耕地系统健康演化过程的时空特征,可为维持和提高耕地系统健康水平提供科学依据。文章以东北黑土区典型地域克山县为研究区,利用突变模型和ArcGIS平台,测算耕地系统健康阈值系数,诊断其健康状态,阐明耕地系统健康演化特征。结果表明:(1)研究区耕地系统健康阈值范围为[0,0.26)、[0.26,0.48)、[0.48,0.71)和[0.71,1.00]4个区间,耕地系统健康状态相应表现为差、中、良和优。(2)1986—2018年研究区耕地系统健康呈现明显的空间分异特征,各乡镇的耕地系统健康在不同时间段存在着健康状态的转化情况。(3)1986—2018年研究区耕地系统健康状况持续下降,耕地系统健康阈值系数下降幅度加快,各乡镇的耕地系统健康阈值系数逐渐趋于均质化,健康阈值系数的差异性持续减小。文章通过构建黑土区典型地域耕地系统健康诊断体系,验证了不同时序耕地系统健康状态差异,提出了建立全生命周期耕地系统健康监测支撑体系的设想,丰富和完善了耕地资源保护和可持续利用的理论与实践。  相似文献   

2.
黑龙江省八五三农场高标准基本农田建设时序分析   总被引:4,自引:0,他引:4  
以黑龙江省八五三农场为例,选取耕地田块为评价单元,对研究区耕地的综合质量和农田建设难度进行评价,并在此基础上对研究区高标准基本农田建设时序进行决策,划分为Ⅰ、Ⅱ、Ⅲ期。结果表明:研究区耕地综合质量等级整体较高,受地形地貌的影响而呈现出一定的地域分布规律;农田建设难度则基本以居民点为中心,形成"中心—外围"的圈层空间分布规律;Ⅰ区耕地基本符合高标准基本农田的要求,Ⅱ区是高标准基本农田建设重点区域,Ⅲ区农田基础差、建设难度大。该研究过程和方法可为垦区高标准基本农田建设和乡镇土地整治提供科学参考。  相似文献   

3.
山东省耕地利用效益的时空差异   总被引:13,自引:0,他引:13  
庞英  张绍江  陈志刚 《经济地理》2006,26(6):1037-1041,1046
文章尝试性地提出耕地利用效益评价指标体系,采用主成分分析、聚类分析和相关分析,并以农业大省山东为例进行实证研究,以揭示区域耕地利用效益的时空差异和特征,为制定提高区域耕地利用效益的对策、为国家制定耕地利用、保护和耕地整理、补偿政策提供参考。研究结果表明,耕地资源利用效益存在着巨大的时空差异;森林覆盖率、人均粮食产量、人力资本水平等8项指标是决定耕地利用综合效益的主要因素。主要结论或政策启示是:政府对耕地的保护政策、补偿政策,不仅要考虑耕地数量,更要考虑耕地利用效益状况,实行高效益高保护、高补偿。  相似文献   

4.
耕地利用集约度实证研究——以重庆市黔江区为例   总被引:1,自引:0,他引:1  
耕地集约利用是农业可持续发展的有效途径。耕地集约度的度量是耕地质量评价的最重要的指标。以重庆市黔江区为例,采用耕地投入强度、利用程度、经济指标、社会指标和生态指标等五个方面来构建耕地利用集约度综合评价指标体系,对黔江区耕地集约度及其变化规律进行了研究。  相似文献   

5.
中国省域农业耕地产出效率实证研究   总被引:5,自引:0,他引:5  
肖勇 《经济问题》2012,(2):70-73
快速的经济增长导致耕地面积以一种非期望速度被转化为非农用地,无论中国目前是否具备满足日益增长的农产品需求能力,耕地产出效率问题都将成为国内外学者当前甚至未来关注的焦点。通过构建中国农业耕地产出效率评价的DEA模型,以中国31个省(市)为研究对象,进行省域农业耕地产出效率测算,并选取气候条件、农业机械技术、外商直接投资以及教育水平等影响因素与效率值进行回归分析,深层次挖掘中国农业耕地产出效率低下的症结所在,最后,提出相应的改进耕地产出效率的对策措施,以期确保国家粮食安全战略的顺利实施和耕地资源系统的健康发展。  相似文献   

6.
基于GIS的林口县域耕地地力评价   总被引:1,自引:0,他引:1  
引言:中国人口众多,人均耕地面积少,农业生产和粮食安女全压力较大。如何利用科技力量,增加单位面积产量,值得研究。通过开展耕地地力评价,为调整种植业布局,实现农业资源的优化配置提供了依据和手段,综合运用GIS的分析、建模和决策等功能[1—2],有效地掌握耕地质量状态,为逐步建立和完善耕地质量的动态监测与预警体系提供支撑。  相似文献   

7.
耕地细碎化问题是制约农业规模经营的主要因素之一,也是农业可持续发展所面临的一项难题。为探讨耕地细碎化问题的研究现状和趋势,文章在参阅国内外文献的基础上从概念、特征、成因、评价方法、影响五个方面对耕地细碎化问题的研究进行了系统回顾,并提出深化耕地细碎化地域性评价方法研究、拓展耕地细碎化影响效应的系统性分析、强化耕地细碎化程度中"度"的测量等今后我国耕地细碎化问题研究的新趋势。  相似文献   

8.
《经济师》2015,(12)
以新疆整体为研究区,借助环境、经济、城市相关专家的理论和研究成果,分析城镇化综合水平与耕地资源的协调发展关系;文章采用综合评价指数、Spearman相关性分析、协调度模型建立以及VAR模型的动态计量等方法揭示新疆城镇化综合水平与耕地资源变动的相关性和协调性。结果表明:2002年-2013年新疆城镇化综合水平与耕地资源呈现正向发展关系,同时运用脉冲响应分析人口城镇化、经济城镇化、社会公共生活、城乡一体化对耕地的影响作用,为新疆城镇化发展与耕地资源的协调发展提供政策建议。  相似文献   

9.
黑龙江省东部垦区耕地利用效益时空分异特征   总被引:3,自引:0,他引:3  
耕地利用效益是衡量耕地生产能力和农业可持续发展的重要指标,它具有一定地域的时空分布特征。以黑龙江省东部垦区的宝泉岭、红兴隆、建三江、牡丹江4个农场群为研究区,选取18个具有代表性的指标,构建研究区的耕地利用效益评价指标体系,利用改进的功效系数法和协调度模型,定量计算研究区1999—2008年10年耕地利用经济效益、社会效益、生态效益及其三者的协调度和耕地利用综合效益值,同时运用ArcGIS手段,对1999—2008年研究区耕地利用综合效益特征进行空间分析。结果表明:1999—2008年,研究区耕地利用效益呈现出不稳定的波动状态,且耕地利用综合效益始终受经济效益、社会效益及生态效益三者之间协调度的影响。研究区的耕地利用效益呈现出东北部和中部高、西北部和南部低的明显区域差异性特征。  相似文献   

10.
采用农户问卷调查法对新疆乌鲁木齐市耕地非农化影响因素进行分析研究.分析乌鲁木齐市耕地非农化过程中农户的行为对耕地非农化的影响,以期为新疆制定耕地非农化过程中耕地保护对策提供依据.  相似文献   

11.
Abstract

The purpose of this paper is to introduce explicitly pleasure and belief in what aims at being a Humean theory of decision, like the one developed in Diaye and Lapidus (2005a). Although we support the idea that Hume was in some way a hedonist – evidently different from Bentham's or Jevons' way – we lay emphasis less on continuity than on the specific kind of hedonism encountered in Hume's writings (chiefly the Treatise, the second Enquiry, the Dissertation, or some of his Essays). Such hedonism clearly contrasts to its standard modern inheritance, expressed by the relation between preferences and utility.

The reason for such a difference with the usual approach lies in the mental process that Hume puts to the fore in order to explain the way pleasure determines desires and volition. Whereas pleasure is primarily, in Hume's words, an impression of sensation, it takes place in the birth of passions as reflecting an idea of pleasure, whose “force and vivacity” is precisely a “belief”, transferred to the direct passions of desire or volition that come immediately before action. As a result, from a Humean point of view, “belief” deals with decision under risk or uncertainty, as well as with intertemporal decision and indiscrimination problems.

The latter are explored within a formal framework, and it is shown that the relation of pleasure is transformed by belief into a non-empty class of relations of desire, among which at least one is a preorder.  相似文献   

12.
Neoliberal political movements advocate privatization of public pension systems. Globalization imposes pressure on nations to conform to neoliberal policy views with respect to the design and structure of social insurance, including public pension systems. The paper begins with an investigation of the economic, ethical and ideological dimensions of the privatization debates in the U.S.; it argues that privatization advocates may be largely moved by ideology, since the other reasons advanced appear weak or unfounded. The second part discusses the history of Social Security, the purposes for its creation, and some of its economic effects. Differences between public and private pension systems are considered. A brief international comparison of some aspects of public pension system finance and benefit structures is presented. The final section considers the ethical, macroeconomic and distributional implications of privatization, prefunding and payroll tax funding, and argues for a pay as you go system financed with income taxes. In order to promote equity, economic security, community, and social cohesion, public pension systems should be universal in coverage. In order to reduce the inequality, income insecurity, and aged poverty generated by market economies, public pension systems ought to be progressive: benefit/contribution ratios should be inversely proportional to income, and progressive income taxes should finance the system. To promote economic growth, the systems should be financed on a pay-as-you-go basis, and should not be prefunded except for an emergency reserve. The fiscal policy recommendations partially depend upon the theory developed by Abba Lerner in the 1940s, and recently advanced by Wynne Godley and Randy Wray: Lerner's “principle of functional finance.”  相似文献   

13.
The payment of interest on reserves has been a common practice in inflationary economies. This policy may seem paradoxical since it involves returning part of the seigniorage, generated by the inflation process, with the intention to finance the fiscal deficit. This paper argues that the motivation for this policy can be captured by the discretionary regime, where the policymaker pays interest on reserves because he is concerned with the erosion of real liquidity by inflation, which is in part beyond his control. However, this policy is an unlikely outcome in the commitment regime, where the policymaker is in full control of inflation.  相似文献   

14.
The multiperiod probit model is presented and Bayesian estimation using the Gibbs sampler with data augmentation is described. As an empirical illustration, the multiperiod probit model is then used to estimate a duration model using employment duration data for the Canadian province of New Brunswick. Bayesian estimation with unobserved heterogeneity is shown to be a simple extension of estimation of a duration model with no unobserved heterogeneity. More importantly, perhaps, some numerical problems encountered by other authors using Maximum Likelihood are avoided.I would like to thank M. Baker, G. Koop, A. Melino and D. Poirier for helpful comments and discussions. I would also like to thank M. Baker for providing his data.  相似文献   

15.
To be creative and make change happen, leaders must do more than simply ‘think outside the box’, as the traditional business manuals suggest, using the popular American expression. After all, the space outside the box is infinitely expansive. Moreover, there can be no guarantee that a solution to the problem will be found. The answer: ‘Think in new boxes.’ This requires developing the right new box; in other words, useful new models, a helpful new approach to a problem. That is the real art of practical creativity. This short article outlines the approach (Thinking in New Boxes) and its application to classic scenario planning with a few examples. The authors also present the ‘Expressway to Scenarios’, an approach that wins in impact and practicality what it loses in deep analysis, by having top executives involved in key steps.  相似文献   

16.
Any adequate analysis of economic globalization necessarily requires fundamental understanding of the worldviews underlying the views expressed with respect to the nature and role of economic globalization. This paper is based on the premise that any worldview can be associated with one of the four basic paradigms: functionalist, interpretive, radical humanist, and radical structuralist. It argues that any view expressed with respect to economic globalization is based on one of the four paradigms or worldviews. It, therefore, discusses four views with respect to the nature and role of economic globalization which correspond to the four broad worldviews. The paper emphasizes that the four views expressed are equally scientific and informative; they look at the nature and role of economic globalization from a certain paradigmatic viewpoint. Emphasizing this example in the area of economic globalization, the paper concludes that there are opportunities for each paradigm to benefit from contributions coming from the other three paradigms.  相似文献   

17.
For the reader who considers economic theory of choice as a special case of a more general theory of action, Hume's discussion of the determinants of action in the Treatise of Human Nature (1739?–?40), in the Enquiry on Human Understanding (1748) and in the Dissertation on Passions (1757) deserves attention. However, according to some modern commentators, Hume does not seem to have given any evidence that would favour what nowadays we would consider as the kind of rationality involved in modern theories of rational choice. On the contrary, this paper arrives at the conclusion that consistency between preferences and choice, like the usual properties of completeness and transitivity, may be considered as outcomes of a mental process, described by means of a decision algorithm that aims to represent Hume's theory of choice.  相似文献   

18.
Following a brief review of the conception of freedom as employedin economic discourse, this paper focuses on the evolution ofthe concept of freedom in the work of Amartya Sen. It tracesthe development of Sen's thought from the capability analysisof the late 1970s to his more recent separation of freedom intoits opportunity and process aspects. While broadly appreciativeof Sen's development of the concept of positive freedom, thepaper identifies some difficulties arising from his definitionof capability as a set of options as well as from his separationof the opportunity and process aspects of freedom. Aspects ofthe relationship between Sen's conception of freedom and thatof Marx are discussed briefly in the context of Sen's recentdiscussion of the market as a source of freedom.  相似文献   

19.
ABSTRACT

Korean chaebol firms, characterized by excessive debt financing and overinvestment, experienced restructuring after the 1997 crisis. By reducing debt financing and thus overinvestment, they tried to reorganize financing structure and ownership structure. Chaebols’ debt reduction turns out to have improved performance. However, polarization between chaebol and non-chaebol firms has become more significant. Even after the crisis, firms that give higher cash flows to a controlling shareholder take more capital investment, indicating that agency problems still exist within chaebols. Chaebol-affiliated firms continue to be more active in R&D than non-chaebol firms. However, the pattern is limited to the group of top 10 chaebols after the crisis.

Abbreviations: KFTC: Korea Fair Trade Commission  相似文献   

20.
Technology is a concept rife with confusion. Here, I argue that technologies can be distinguished as a combination of type of producer and an idealized artefact life history. Using this definition, a number of technologies are identified. The first technology historically, in the Protostomes, was the production of individual or family dwellings. Next came objects such as spider webs for trapping prey. Stigmergy followed, with the social insects, as a collective endeavour to construct a mega-structure using simple rules of accretion. Some birds and primates began to make tools, or simple technological objects whose function is closely related to their form. Humans are distinguished by their ability to make machines. Traditional technology took place once people voluntarily organised into groups with specialised knowledge to produce more complex objects and structures. Monumental objects like ceremonial pyramids came with the command economies of the early agrarian societies, which also resulted in a new category of artefact, the network. Finally, with modern civilizations came ad hoc accretion, or population-level adding-on, to make truly complex technological systems. Developing a theoretical framework within which artefacts, production processes and ways of interacting with them are identified should help the study of technology to become more scientific.  相似文献   

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