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91.
There is currently a growing interest in the spatial causes of poverty, particularly its persistence. This paper presents methodological innovations that have been developed for investigating the relationship between physical segregation and economic marginalization in the urban environment. Using GIS to layer historical poverty data, contemporary deprivation indexes and space syntax measures of spatial segregation, a multivariate system has been created to enable the understanding of the spatial process involved in the creation and stagnation of poverty areas as well as to analyse the street segment scale of configuration.  相似文献   
92.
Neglect by most geographers, especially political geographers, of one of the major issues of our time, that of war and peace, is criticized. Theories, methods and advances in the field of international relations are briefly reviewed and suggestions are offered to bring the geographic profession to a greater awareness of the major research issues. Sources for the study of international conflicts are listed.  相似文献   
93.
周麟  田莉  张臻  李薇 《地理学报》2018,73(8):1433-1448
研究基于空间句法理论与方法,结合不同时期的数字化历史地图,从街道网络显型、“局部—整体”层级关系及运转效率等三方面探讨民国以来北京老城的街道网络演变进程。结果表明:① 政权更替是其演变的分水岭。民国时期,老城街道网络由封建隔离结构向现代通达结构转型,环环相扣、中轴对称式的整合、穿行核心格局同时被打破。1949年中华人民共和国成立后,街道网络的几何格网特征越发明显,“环形+大格网”式的核心运动骨架凸显,不同街道段的可达性与穿行频率则逐渐趋同。② 老城各子区域的可达性层级关系在百余年来持续变化,穿行频率层级关系则保持稳定,与其他区域相比,东城的可达性与穿行频率优势明显。③ 政权更替之际新结构的集中嵌入与随后规划建设的路径依赖使得老城全域的运转效率历经“下降→上升→下降→上升”的起伏演变过程。这一过程同样出现在东城、西城与外城,但更强的几何格网特征促使前者的两次上升幅度较大,运转效率也相对较高,而皇城的运转效率则随小规模封闭系统的日益开放呈阶梯式下降。概括来讲,研究不仅运用数字化手段系统梳理了北京老城的街道发展史,为如何更好地保护古都风貌,传承历史文脉提供了街道网络视角的逻辑支撑,对于空间句法的理论算法体系也进行了一定拓展。  相似文献   
94.
跨界道路交通对同城化地区时空联系影响研究:广佛案例   总被引:2,自引:2,他引:0  
同城化是区域内城市发展到一定阶段的产物,而交通是同城化时空联系产生的重要基础。利用空间句法以及时间地图方法,分析广佛时空结构特征,多方面探讨跨界道路建设对广州与佛山时空联系的影响。结果表明:① 广佛时空结构特征方面,5 km、10 km句法整合度模型呈现以广州内环高速范围内地区为中心的极化格局特征,佛山中心城区位于节点位置;20 km、100 km整合度模型中广佛中心集聚特征明显;广佛时间地图呈东西方向收缩。② 跨界道路影响方面,通行后越接近交界区域,时间距离偏移越大,广州南部地区与南海、顺德时间成本改善明显。③ 跨界道路通行有利于不同尺度下路网可达性整体水平的提高,能为广佛路、陈村大桥、禺山西等道路分流部分交通流。空间句法与时间地图方法的使用识别了不同尺度上广佛等级差异与交通潜力,且对地理空间进行了时空转换,结论能为今后城市功能整合提供参照,并为相关研究提供新的分析维度和视角。  相似文献   
95.
Spatio-temporal simulation of the geopolitical environment system   总被引:1,自引:0,他引:1  
Geographical circumstances are the fundamental background for all kinds of geopolitical events. The geopolitical environment system (GES) refers to a system that combines both physical and anthropogenic subsystems. Research on the geopolitical environment system simulation is a key to understanding the international geopolitical phenomenon. The theory of GES arose from the integration of the traditional geopolitics and earth system sciences. As an interdisciplinary system composed of many different fields, integrated reviews and a metadata study of GES are urgently needed. This paper presents a comprehensive view into the origination and advance of the GES theory. The conceptual framework of the GES is described in detail. The methodology for simulating and forecasting geopolitical events is also provided. It is proposed that the core topics of the GES science may include, but are not limited to, issues as data acquisition technologies; principles on the interactions between multiple subsystems (or factors) at different scales; evaluating and mitigating the global geopolitical risks, including the political risks, economic risks, the social risks, the environmental risks and the technological risks; and forecasting the geopolitical events with machine learning and artificial intelligence techniques.  相似文献   
96.
Analysing a sample of 3,033 environmental conflicts around the globe, we compared conflicts reporting no human health impacts to those reporting health impacts linked to toxic pollution. Our study suggests four main findings. First, health impacts are a key concern for working-class communities. Second, the long-term effects of toxic pollution undermine communities' ability to act preventively. Third, industrial activities, waste management and nuclear energy conflicts are more likely to report health impacts than other economic activities. Last, mobilising groups are reluctant to consider the closure of a polluting project a successful outcome because of the persistence of toxic pollution across time. Our results contribute to a better understanding of the dynamics of what we have termed ‘environmental health conflicts’ (EHCs).  相似文献   
97.
Current enthusiasm for the potential of sustainable agricultural development must be based on a realistic assessment of the dynamics used by specific farming sectors. This study highlights the structural limitations that impede agricultural progress and explains why it is necessary to overcome these impediments in a case study of Brazil, one of the world's main agricultural exporters. In Brazil, the commodity-exporter large-farmers production chain is largely controlled by multinational corporations, with the investment of national capital a mere 12.4% in the technology-intensive sectors of the soy business (composed of seed production, fertilizers, pesticides, machinery, trading companies). The agricultural sector's future depends on increasing the share of national capital into domestic businesses and confronting the current and simplistic strategy of expansion into new agricultural frontiers, which often have high social and environmental costs. The future of family farmers depends on comprehensive development alternatives and challenging the current policies, since current development has been restricted to the 17.9% of family farmers who have access to rural credit, whom are mostly based in the Southern region of Brazil.  相似文献   
98.
少有学者测度规划道路系统分析出的空间形态与规划师空间形态规划意图的一致性。为更好地落实规划师的空间形态规划意图,以安厚镇为例,提出"基于GIS和空间句法的空间形态一致性测度"方法。主要思路为:首先,基于规划的城镇道路系统用GIS空间分析技术及集成度、智能度等句法变量分析新一轮城镇空间形态,然后,测度分析出空间形态与空间形态规划意图的一致性。测度结果表明经分析出的城镇空间形态与规划师本意的一致性有待改善,主要表现为城镇发展轴整体智能度较低、可理解性不高,城镇空间拓展主轴较大程度偏离原规划拓展方向,城镇发展次轴对空间结构的引导效用高于主轴。  相似文献   
99.
以福建厦门岛为例,通过空间句法结合核密度估计法等GIS技术,在分析不同规模(社区、市区)购物中心和路网形态分布的基础上,通过逐步回归方法探究路网形态对城市购物中心布局的影响。结果表明:购物中心总体呈现多中心轴向发展的集聚与扩散并存的空间分布特征,购物中心的级别越高,聚集程度越弱;路网形态的空间差异显著,高穿行度与整合度的路网形成从厦门岛中西部地区向四周延伸辐射的路网形态,这与岛内的主要交通走廊契合;局部路网形态对购物中心的影响大于全局性路网,购物中心对路网形态的穿过与可达特性均有较大的依赖性;社区购物中心与局部路网的穿行度和整合度正相关,市区购物中心与全局路网的穿行度正相关。  相似文献   
100.
New Zealand fisheries legislation provides commercial fishing rights to holders of individual transferable quota (ITQ). The settlement of fisheries claims against the Crown by Mäori, New Zealand's indigenous people, brought about the transfer of ITQ holdings to Mäori, and an obligation on the Crown to recognise and provide for indigenous (customary) fishing rights over fishing grounds and other areas that have been of special significance to Mäori. Some types of customary fishing areas exclude commercial fishing and could affect recreational fishing. Fisheries legislation requires that regulatory measures be put in place to avoid, remedy or mitigate the adverse effects of fishing. The Government also aims to protect marine biodiversity by having 10% of New Zealand waters in some form of protection by 2010. The legislative processes for protecting the marine environment and establishing customary fishing areas include assessment of effects on fishing rights. This paper explores the conflicts that arise from legislative obligations to uphold the rights of fishers, to sustain fishstocks and to protect the marine environment. The paper concludes that inconsistent legislative obligations and their disparate processes have led to spatial conflicts and a race for the allocation of space. Legislative obligations need to be integrated to maintain a balance between use of fisheries resources and protection of the marine environment.  相似文献   
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