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971.
Geography of crime research dates back to the early 1800s, most of which in English and in the context of the United States and Europe, but with a growing and significant literature studying the developing world. We contribute to this literature through an application of social disorganization theory in a Latin American context: Campinas, Brazil. We consider a number of property and violent crime types using census tracts as the spatial unit of analysis. Implementing a spatial regression method, we find support for social disorganization theory, but not as strong as similar studies in Europe and North America. However, because of the context of Campinas, Brazil, a different understanding of the local conditions proves to be important for understanding the geography of crime in this context. The implications of these results are discussed in the context of theoretical developments as well as crime prevention initiatives.  相似文献   
972.
诸多沉积记录揭示,中国北方早期历史,气候环境大致经历了3580-3050 cal a BP、3050-1800 cal a BP两个阶段;前者为稳定的湿润气候期,后者为逐渐趋于干燥的气候期;前期为中国历史上第二个王朝—商王朝统治期,政局稳定,社会承平,王朝较为稳定地传承了500余年,是中国历史上“寿命”最长的朝代;后者对应西周—东周(春秋—战国)—秦—西汉—东汉—三国等朝代,在不足1300年内,政权格局多次更迭,表现出一种与前期截然相反的社会政治生态。这期间,以都城为标志的王朝的重心,具有向东南迁移的趋势。年代对比发现,商代夏、周代商、平王东迁、西汉甚至东汉灭亡等改朝换代的社会政治事件,都与沉积记录所指示的气候环境的显著变化(恶化)对应。研究再次证实早期的中国历史与气候变化存在密切的关系,并认为如下两个因素可以阐述这种关系的存在:① 中国北方地理环境空间是扇状的,且自然环境具有梯度变化的特征,这种地理环境格局叠加在气候变化之上,具有特殊的加剧与舒缓区域社会矛盾的作用。② 小农经济具有对气候变化的特殊敏感性。对西汉所做的案例考察认为,不尽合理的社会体制往往通过一系列反馈作用将这种敏感性在气候恶化阶段“放大”,随之形成一系列连锁反应,由此造成的各种危机成为王朝崩溃重要因素。  相似文献   
973.
How watershed collaborations adapt to changing conditions is an enduring question in collaborative resource management. Our research examined the goals and structure of collaborations within watersheds subject to the same federal and state regulations, but at different restoration states. We employed semistructured interviews, document analysis, and participant observation to complete our qualitative research. Our results suggest that policy stakeholders’ understandings of ecological and social attributes influence watershed goals. Within the impaired system, collaborations invested in shifting public perception to engender support for longer term biophysical restoration. Within the restored watershed, collaborations achieved dramatic biophysical improvements but were challenged in addressing social benefits of restoration. Redefining restoration to incorporate social and ecological systems at the outset provides the opportunity to set benchmarks for measuring success that incorporate social and ecological factors, and to create institutions adept at responding to shifting restoration states.  相似文献   
974.
乡村旅游发展能够给当地居民带来巨大的就业机遇,社区参与能够提高乡村居民整体的社会保障水平,这为吉登斯所倡导的“第三条道路”社会保障思想提供了现实依据,也为乡村旅游实现精准扶贫效果提供了创新路径。洛阳栾川重渡沟村的社会保障在乡村旅游的影响下经历了3个阶段,1999年前未发展乡村旅游时受国家干预主义影响较大,1999—2004年乡村旅游发展体现了经济自由主义的影响,而2004年至今的实践体现了经济自由主义与国家干预主义的融合,实现了政府与市场、公平与效率、权利与责任的相对均衡,实践中已初步实现了以就业保障为基础、以养老保障及最低生活保障等为内容的乡村社会保障的全面提高。研究表明,西方背景下形成的国家干预主义及经济自由主义在中国乡村市场经济实践中有着不同的诠释及呈现方式,乡村旅游精准扶贫的关键是社区力量的觉醒及培育,其创新路径是实现“以旅游换保障”,即实现乡村旅游经济功能向社会功能的转变。  相似文献   
975.
Understanding urban functions and their relationships with human activities has great implications for smart and sustainable urban development. In this study, we present a novel approach to uncovering urban functions by aggregating human activities inferred from mobile phone positioning and social media data. First, the homes and workplaces (of travelers) are estimated from mobile phone positioning data to annotate the activities conducted at these locations. The remaining activities (such as shopping, schooling, transportation, recreation and entertainment) are labeled using a hidden Markov model with social knowledge learned from social media check-in data over a lengthy period. By aggregating identified human activities, hourly urban functions are inferred, and the diurnal dynamics of those functions are revealed. An empirical analysis was conducted for the case of Shenzhen, China. The results indicate that the proposed approach can capture citywide dynamics of both human activities and urban functions. It also suggests that although many urban areas have been officially labeled with a single land-use type, they may provide different functions over time depending on the types and range of human activities. The study demonstrates that combining different data on human activities could yield an improved understanding of urban functions, which would benefit short-term urban decision-making and long-term urban policy making.  相似文献   
976.
977.
Numerous cities in developing regions worldwide are expanding at a tremendous rate. This requires adequate strategies to address the needs of these growing cities with diverse populations. Nonetheless, the development of urban policies is often hampered by the lack of reliable data or insight in the socio-spatial dynamics of this urban expansion. This paper therefore presents ASSURE, a spatially and temporally explicit model that can simulate urban growth and intra-urban social segregation, taking into account alternative policy strategies and expected social dynamics. The model has a flexible structure that allows incorporating specific city conditions that influence residential decision-making and adapting the simulation to the data available. This, in combination with the transparent model structure, makes ASSURE a potentially valuable decision support tool for urban planning. The potential is demonstrated with an example where the urban growth of and social segregation in Kampala (Uganda) is simulated based on (semi-)quantitative and qualitative data for ca. 800 households collected through interviews. The results of the simulations show that depending on the scenario, the spatial segregation and accessibility problems will evolve highly differently.  相似文献   
978.
Communities in the rural developing world often sit at the margin of market, migration, and technology exchanges. They are arguably becoming more interconnected and networked than ever before. This article seeks to expand on an understanding of natural resource access in the rural developing world by combining social network analysis (SNA) data and geographic position data obtained via Global Positioning System (GPS) and participatory mapping in rural South Africa. This work therefore utilizes a sociospatial framework in understanding natural resource use and access in a community-level analysis. Notably, in our study we find very little association among natural resource use, access, and social position with even the most tolerant measure but enough association so as not to dismiss the relationship completely. We believe that our results can inform investigations of both resource access and social network position and conclude that a subsequent possibilist approach to human–environmental interactions would be an ideal framework for this methodology and potentially for sociospatial studies more widely.  相似文献   
979.
西安快速城市化边缘区社会脆弱性评价与影响因素   总被引:17,自引:7,他引:10  
脆弱性理论是分析人地相互作用程度、机理与过程的重要工具,为可持续性评估研究提供了新的视角。将社会脆弱性工具应用到城市边缘区研究中,视快速城市化为主要干扰,选取西安城市边缘区所辖街道为基本单元,从暴露度、敏感性、适应能力3方面构建社会脆弱性评价框架与指标体系,综合运用熵值法、函数模型法以及遥感与地理信息系统技术对社会脆弱性程度进行评价,揭示社会脆弱性空间分异格局,探究社会脆弱性关键影响因素及其影响机制。结果表明:① 西安城市边缘区的暴露度格局呈现出自中心向外围渐趋减缓的特征;敏感性程度的高、低分布与暴露度的低、高分布在空间上具有相似性;适应能力的空间规律性不明显;② 社会脆弱性空间分布不均衡,以中、低等级为主,低等级街道分布在城市内边缘区,中等级街道分散在城市外边缘区;③ 建设用地面积比重等8个因子对社会脆弱性有重要影响,土地利用方式与景观格局的变化以及物质与社会发展的不平衡是城市边缘区社会脆弱性形成的主要原因,社会系统体制转换阶段的差异进一步加剧了社会脆弱性;④ 城市边缘区应通过优化系统内部结构和功能以适应城市化的扰动,包括制定适应性管理政策和加强城市边缘区社会适应能力建设。  相似文献   
980.
中国城市空气质量时空演化特征及社会经济驱动力   总被引:11,自引:1,他引:10  
蔺雪芹  王岱 《地理学报》2016,71(8):1357-1371
城市空气污染是中国在快速城镇化和经济发展过程中亟待解决的难题。利用2013年和2014年全国城市空气质量数据,综合ArcGIS空间分析和统计分析,从年度、季节、月份、小时4个时间尺度比较归纳了全国城市空气质量的时空间演化特征,并采用空间计量模型,从全国和区域两个空间尺度,量化分析了城市空气质量变化的社会经济驱动力。结果表明:① 全国城市空气质量全年达标天数比例增加,但空气污染程度加重,高污染区域恶化态势明显;② 城市空气质量与生产生活活动表现出一定的时间耦合性,基本呈现“日出趋差、日落趋优”的态势;③ 全国城市空气污染表现出“东重西轻、北重南轻”的空间格局,区域一体化态势明显;④ 区域城市空气污染的总体程度和分布结构具有明显的分异特征,区域空气污染形成和演化路径可基本归纳为:“重点城市污染加重—重点城市污染扩散—区域整体污染加重—重点城市引领治污—区域污染联防联控—区域整体污染减轻”;⑤ 从全国层面看,能源消耗、工业化和技术进步是推动城市空气质量恶化的重要因素,经济发展对城市空气质量改善具有显著的推动作用。⑥ 受各地区资源环境基础和社会经济发展阶段影响,各类社会经济因素对城市空气质量改善的驱动方向和驱动强度差异明显。在结论的基础上,讨论了中国经济发展和环境变化关系的区域分异以及发展理念。  相似文献   
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