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1.
娄胜霞 《经济地理》2011,31(8):1358-1363
以公里格网为基本单元,基于GIS技术,建立包括地形起伏度、温湿指数、水文指数和地被指数的人居环境自然适宜性评价模型,系统评价遵义市不同地区的人居环境自然适宜性与限制性。研究表明,遵义市人居环境以适宜性为主要特征,自然适宜程度整体呈现出由西北向东南递增的趋势,其中44.41%为一般适宜区、54.13%为比较适宜区以及极小比例为临界适宜区;遵义市人居环境自然条件较好,地形、地被、水文和气候对人口分布的限制性不明显,其中地形条件对人口分布的限制性最强,其次是地被条件。  相似文献   

2.
吕东辉  张郁  刘岳琪 《经济地理》2022,42(1):160-167
以松嫩平原乡村地区32个县域单元为例,基于空间自相关分析及人口集中度指数、经济集中度指数、人口与经济分布不一致指数的测度,揭示乡村收缩背景下松嫩平原乡村地区人口—经济的空间耦合关系。结果表明:(1)2000—2018年,松嫩平原乡村地区人口数量先增加后减少,人口密度空间分布呈现"南密北疏"的格局。(2)人口空间分布的关联性较强,呈现典型的集聚分布模式,人口集中度指数南高北低且高值区域逐渐向北扩展。(3)经济集中度分布格局多呈现"双核"模式,且经济空间分布不均衡性大于人口空间分布的不均衡性。总体来看,近20年来,松嫩平原乡村地区人口—经济的空间耦合类型中,协调发展型和经济迟滞型的县域类型居多。  相似文献   

3.
基于全国四次人口普查数据,运用反距离权重插值法、探索性空间数据分析方法、人口分布指数等,以县域为基本单元,探究湖南省1982—2010年人口分布的时空变化特征及主要影响因素。结果表明:(1)1982年以来,湖南省人口密度呈现出"东高西低"的分布格局,并以高值区为核心圈层梯级递减,高值区范围扩大,中值区范围缩小,低值区范围基本保持不变;(2)在人口增速总体趋缓的背景下,同一时期人口密度低、中、高值区人口增长速度依次递增,人口分布地区差异扩大;(3)人口分布的空间自相关性不断增强,冷热点格局基本稳定,热点区有所增加,冷点区有所减少,冷热点区在空间上呈集聚分布,人口分布不均衡化趋势加剧;(4)影响湖南省人口分布格局及变化的因素众多,自然地理条件和资源禀赋差异奠定了人口分布的基本格局,不均衡的经济发展不断重塑着人口分布格局,渐进式的区域发展战略对人口分布格局有重要的导向作用。全面提高"以人为本"的城镇化质量,稳步推进新型城镇化健康持续发展,是促进湖南省人口分布格局优化的必由之路。  相似文献   

4.
基于ESDA的中国人口空间格局及影响因素研究   总被引:10,自引:1,他引:9  
利用ESDA技术,基于GIS平台对2005年中国人口空间格局进行研究,发现2005年全国县域人口密度不仅数值差距较大,基尼系数达0.55,而且空间自相关性较强,Mom's I指数为0.42.京津冀、长三角、珠三角、四川盆地、东北经济带仍是全国人口最密集地区.局部空间自相关结果显示,京津冀、长三角、珠三角和四川盆地是高高型人口集聚区.哈尔滨、长春、银川、昆明等城市地区是高低集聚区.低高型区域集中在高高型区域四周.西北干旱区、内蒙古北部、东北北部山区属于低低集聚区.将人口密度分为五级,通过人口重心观察,以及将人口密度与自然和经济因素叠加,发现气候和海拔高度仍是影响人口分布的主要因素.产业结构和交通对全国人口格局影响显著.自然因素不同的组合形式将对人口格局产生不同的影响,其中气候和地形因素长期稳定地影响人口空间格局,但其对人口空间分布的约束力将随着技术进步而降低.经济因素是人口空间格局短期变动的主要原因.  相似文献   

5.
人居环境的全方位提升是旅游资源非优区可持续发展的关键逻辑节点。文章利用空间自相关指数、空间变差函数和地理加权回归模型,测度2015年吉林省旅游资源非优区人居环境空间格局及其影响因素。结果显示:(1)旅游资源非优区人居环境水平整体不高,空间分异特征不明显,高值集中于东南部通化市,低值分布于中部辽源市和四平市,子系统呈现生态环境社会经济环境基础设施环境居住环境。(2)旅游资源非优区人居环境水平相似地区空间集聚,均质性和空间自组织性突出,空间格局呈现两端高、中间低的"哑铃型"结构,西北部存在若干"柱状峰体"。(3)社会经济环境、居住环境、基础设施环境和生态环境对旅游资源非优区人居环境影响程度的空间差异显著,社会经济环境以正向影响为主,居住环境以负向影响为主,基础设施环境对东南部影响较大,生态环境影响的空间异质性最不明显。  相似文献   

6.
在区域发展环境变化及发展格局转变情况下,文章引入地理集中度、不一致指数及不均衡指数等方法,对比分析2000—2015年长江三角洲人口、经济地理集中度及人口与经济不一致指数的时空格局演变趋势,并基于面板数据回归对人口与经济不一致指数的影响因素进行实证研究。结果表明,在经济分布向边缘区扩散的格局下,人口分布总体呈现向核心区集聚的态势,由此带来的人口与经济不一致指数变化主要表现为核心区的上升与边缘区的下降,且人口与经济空间布局的协调性有所提高。对不一致指数影响因素的定量分析表明,市场力量、政府政策及城市发展状况等都对人口与经济分布不一致性产生重要的影响。  相似文献   

7.
以河南省人口总体以及各地市数据为基础,采用Arc?GIS从空间演化的角度进行定量研究,研究结果表明:河南省人口整体逐年增加,呈"中心性"趋势,但增长速率放缓,人口分布非均衡性和空间集中性呈现不断增强趋势;高人口密度地市逐渐增多,低人口密度地市的范围逐渐变小,各个地市之间人口密度呈现显著性差异,地市的人口密度大于河南省总体的人口密度;而人口在空间分布的不平衡,主要受制于自然、历史、经济和政策等众多因素的综合影响,可从构建多中心区域结构、调整区域产业空间布局、平衡区域资源配置以及优化基础设施的区域差异方面入手,从而保证区域的可持续发展.  相似文献   

8.
罗君  石培基  张学斌 《经济地理》2020,40(6):106-115
以黄河上游的兰州—西宁城市群为例,基于DEM数据、乡镇尺度的人口普查数据和土地利用数据,运用土地利用影响模型和GIS格网技术实现人口数据空间化,进而探讨人口分布格局与地形要素的关系,结果表明:①人口空间化结果达到精度要求,能反映兰西城市群人口分布的实际情况。②兰西城市群人口东密西疏的分布格局基本稳定,呈现"大分散、小集中"的分布特征;分布形态与黄河干支流水系形态高度相似,湟水谷地呈"鱼骨状"分布,东部黄河流域呈带状分布。③人口分布的非均衡性增强,极度稀疏区面积扩大,人口高度分散分布;稠密区的人口极化效应增强,兰州、西宁和临夏是3个人口集聚中心。④人口分布随地形变化呈现垂直梯度效应和中低海拔河谷盆地指向,随着地形起伏度、海拔和坡度增大,人口密度不断降低,人口主要分布于地形起伏度小于200 m、海拔低于2 500 m、坡度小于15°的河谷盆地内。  相似文献   

9.
基于PSR模型构建乡村人居环境脆弱性评估体系,采用指标聚合、地理加权回归等方法对2010—2018年湖南省乡村人居环境脆弱性及其响应指数的影响因素进行研究。结果显示:(1)湖南省乡村人居环境脆弱性呈明显下降趋势,其中压力指数下降速度最慢,响应指数下降速度最快,2014—2018年下降幅度大于2010—2014年;(2)脆弱性高值区集中分布在大湘西和洞庭湖流域,脆弱性低值区集中分布在长株潭城市群周围,总体上呈现“西高东低”的空间格局特征;(3)脆弱性响应指数影响因子的作用强度在空间上具有差异性,自然因素是影响乡村人居环境脆弱性响应指数的主导因素,经济因素起到关键作用,人口、环境以及区位因素在乡村人居环境脆弱性响应机制中起到重要作用。不同区域应根据脆弱性根源的差异,科学开展乡村人居环境整治,不断完善脆弱性响应机制,促进乡村振兴战略的顺利实施。  相似文献   

10.
建国以来山东省人口分布地域格局及集疏变化分析   总被引:1,自引:0,他引:1  
张慧 《经济地理》2012,32(10):28-35
采用人口密度、人口集疏度和人口稳定度等指标来研究建国以来山东省人口分布地域格局及集疏程度的时空变化情况。结果表明:①建国以来山东省人口分布一直保持较为均衡的态势,但基尼系数不断增大,人口分布日趋集中;②山东省人口分布地域格局从根本上受到自然环境条件的约束,人口密度随自然环境差异表现出沿"鲁西平原区—鲁中南低山丘陵区—半岛丘陵区"由西南向东北逐渐降低,且呈现出"高—高"关联和"低—低"关联的分布模式;③山东省人口空间集疏不断发展并将继续强化。前30年各县域人口普遍增加,人口集疏不明显,人口分布相对稳定。近30年各县域人口增减趋于普遍,人口集疏日益加剧,集疏程度不断提高,且人口流入/流出趋于频繁,影响范围越来越广;④改革开放是山东省人口分布格局和集疏快速变化的一个转折点。改革开放以后国家和区域发展政策发生了巨大变化,地区发展差异成为人口集疏变化的重要原因,城市化成为人口流动的强大推力,极大地促进了山东省人口的再分布。  相似文献   

11.
John Stuart Mill has traditionally been portrayed as self-contradictory and failing to construct a unified social theory. Recent scholarship, however, has challenged this view, finding Mill's work to be creatively synthetic in bridging the antinomies inherent in liberal democratic thought. This revisionist interpretation of Mill is advanced by an understanding of his theory of justice and its role in shaping his policy positions on issues such as welfare, education, voting rights, property rights, taxation, government intervention, and the future of capitalism.  相似文献   

12.
Arik Hesseldahl In the aftermath of the September 11 attacks, U.S. officials quickly turned their attention to other potential targets, including California's Golden Gate Bridge. What would happen if terrorists took down the bridge between San Francisco and Marin County? How much of the region would be affected and for how long?  相似文献   

13.
中国拥有世界五分之一强的人口 ,收入又在迅速增长。因此 ,国际上很自然地会考虑或推测她在今后的几十年是否有能力养活自己。中国的人口预计将从 2 0 0 0年的 1 2 8亿增长到 2 0 2 0年的 1 4 6亿 ,和 2 0 3 0年的 1 4 9亿。与此同时 ,人均收入的增长将导致对家畜和鱼类产品更大的需求 ,因而对饲料的需求也将有很大的增长  相似文献   

14.
This article seeks to evaluate the appropriateness of a variety of existing forecasting techniques (17 methods) at providing accurate and statistically significant forecasts for gold price. We report the results from the nine most competitive techniques. Special consideration is given to the ability of these techniques to provide forecasts which outperforms the random walk (RW) as we noticed that certain multivariate models (which included prices of silver, platinum, palladium and rhodium, besides gold) were also unable to outperform the RW in this case. Interestingly, the results show that none of the forecasting techniques are able to outperform the RW at horizons of 1 and 9 steps ahead, and on average, the exponential smoothing model is seen providing the best forecasts in terms of the lowest root mean squared error over the 24-month forecasting horizons. Moreover, we find that the univariate models used in this article are able to outperform the Bayesian autoregression and Bayesian vector autoregressive models, with exponential smoothing reporting statistically significant results in comparison with the former models, and classical autoregressive and the vector autoregressive models in most cases.  相似文献   

15.
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   

16.
In principle, we want regulatory programs to be based on current realities, as reflected for example in the best knowledge of relevant experts. That would imply that old rules now on the books should be consistent with today's knowledge base, not just what was known when a rule or standard was originally set. This paper reports on a survey of US programs, examining how often existing rules are actually updated in light of better knowledge, and identifies five programs that attempt to make policy routinely adaptive. These programs exhibit what we term Planned Adaptation: they both revise rules when relevant new knowledge appears, and take steps to produce such improved knowledge. While Planned Adaptation is rare, it is used in several nationally prominent programs, including air pollution, airplane safety, and drug safety. Planned Adaptation is a policy tool that deserves more attention.  相似文献   

17.
Synopsis Classification is an important activity that facilitates theory development in many academic disciplines. Scholars in fields such as organizational science, management science and economics and have long recognized that classification offers an approach for ordering and understanding the diversity of organizational taxa (groups of one or more similar organizational entities). However, even the most prominent organizational classifications have limited utility, as they tend to be shaped by a specific research bias, inadequate units of analysis and a standard neoclassical economic view that does not naturally accommodate the disequilibrium dynamics of modern competition. The result is a relatively large number of individual and unconnected organizational classifications, which tend to ignore the processes of change responsible for organizational diversity. Collectively they fail to provide any sort of universal system for ordering, compiling and presenting knowledge on organizational diversity. This paper has two purposes. First, it reviews the general status of the major theoretical approaches to biological and organizational classification and compares the methods and resulting classifications derived from each approach. Definitions of key terms and a discussion on the three principal schools of biological classification (evolutionary systematics, phenetics and cladistics) are included in this review. Second, this paper aims to encourage critical thinking and debate about the use of the cladistic classification approach for inferring and representing the historical relationships underpinning organizational diversity. This involves examining the feasibility of applying the logic of common ancestry to populations of organizations. Consequently, this paper is exploratory and preparatory in style, with illustrations and assertions concerning the study and classification of organizational diversity.  相似文献   

18.
The buildup of so-called greenhouse gases in the atmosphere — CO2 in particular-appears to be having an adverse impact on the global climate. This paper briefly reviews current expectations with regard to physical and biological effects, their potential costs to society, and likely costs of abatement. For a worst case scenario it is impossible to assess, in economic terms, the full range of possible non-linear synergistic effects. In the most favorable (although not necessarily likely) case (of slow-paced climate change), however, it seems likely that the impacts are within the affordable range, at least in the industrialized countries of the world. In the third world the notion of affordability is of doubtful relevance, making the problem of quantitative evaluation almost impossible. We tentatively assess the lower limit of quantifiable climate-induced damages at $30 to $35 per ton of CO2 equivalent, worldwide, with the major damages being concentrated in regions most adversely affected by sea-level rise. The non-quantifiable environmental damages are also significant and should by no means be disregarded.The costs and benefits of (1) reducing CFC use and (2) reducing fossil fuel consumption, as a means of abatement, are considered in some detail. This strategy has remarkably high indirect benefits in terms of reduced air pollution damage and even direct cost savings to consumers. The indirect benefits of reduced air pollution and its associated health and environmental effects from fossil-fuel combustion in the industrialized countries range from $20 to $60 per ton of CO2 eliminated. In addition, there is good evidence that modest (e.g. 25%) reductions in CO2 emissions may be achievable by the U.S. (and, by implication, for other countries) by a combination of increased energy efficiency and restructuring that would permit simultaneous direct economic benefits (savings) to energy consumers of the order of $50 per ton of CO2 saved. A higher level of overall emissions reduction — possibly approaching 50% — could probably be achieved, at little or not net cost, by taking advantage of these savings.We suggest the use of taxes on fossil fuel extraction (or a carbon tax) as a reasonable way of inducing the structural changes that would be required to achieve significant reduction in energy use and CO2 emissions. To minimize the economic burden (and create a political constituency in support of the approach) we suggest the substitution of resource-based taxes in general for other types of taxes (on labor, income, real estate, or trade) that are now the main sources of government revenue. While it is conceded that it would be difficult to calculate the optimal tax on extractive resources, we do not think this is a necessary prerequisite to policy-making. In fact, we note that the existing tax system has never been optimized according to theoretical principles, and is far from optimal by any reasonable criteria.During the academic year 1989–90 Dr. Ayres was at the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.During the summer of 1989 Mr. Walter was a member of the Young Scientists' Summer Program at IIASA.  相似文献   

19.
20.
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   

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