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251.
This article aims to explore the relationship between individual adaptive actions and enhancement of community resilience to climate change as a communal objective. It proposes to pay attention to the concept of reflexivity as the primary individual capacity to link adaptive actions and community resilience. Drawing on the field research conducted in northern Ghana in 2015, this article specifically examines life histories of four small farmers and shows that they individually take adaptive actions and reflect on these actions. However, little opportunity exists for them to systematically communicate the reflections with others to learn from their experiences, nurture collective agency and enhance community resilience. The article concludes by outlining new strategies needed to facilitate the communication in particular cultural and policy contexts.  相似文献   
252.
从社会网络视角,采用中心度、社团划分和结构熵等社会网络指标,探究全球贸易网络的空间格局及演化特征,重点分析中国在网络中的社团归属及其地缘战略启示。研究表明:随着时间推移,发展中国家的群体性崛起使得全球贸易网络结构呈现日益多元化的复杂格局;全球贸易网络的社团演化经历了发达国家主导、亚洲崛起的萌芽、亚洲社团的分离和“三足鼎立”四个阶段,中国从被支配的边缘地位逐步走向“舞台中央”;中、美、德三国在全球市场细分过程中形成一种“错位竞争”关系,亚太、中东、非洲和拉美地区成为大国之间争夺贸易市场的博弈区域。中国应首先立足于亚太地区,通过“一带一路”倡议延伸至中东、非洲和拉美地区,将经济优势转化为全球战略影响力。  相似文献   
253.
古尔班通古特沙漠南缘丘间地梭梭群落蒸散特征   总被引:1,自引:0,他引:1       下载免费PDF全文
王泽锋  胡顺军  李浩 《干旱区地理》2018,41(6):1303-1309
根据2016年古尔班通古特沙漠南缘丘间地梭梭生育期定点观测的土壤水分、气象要素等资料,基于水量平衡原理估算了梭梭生育期蒸散量,分析了蒸散变化规律。结果表明:(1)在梭梭生长季,降雨量为206.7 mm,降雨分布不均,梭梭萌发期,降雨量最多;梭梭生长旺盛期,月降雨量逐月减少;梭梭枯落期,降雨量最少。(2)在梭梭生长季,梭梭群落0~400 cm土壤贮水量变化整体呈下降趋势,梭梭萌发期是土壤贮水量盈余期,生长旺盛期和枯落期为土壤贮水量亏损期;梭梭群落发挥土壤水库效应,依靠生长季前土壤蓄水来弥补梭梭群落生长季需水缺额。(3)在梭梭生长季,蒸散量变化特征为多峰曲线,峰值主要出现在降雨集中期,最低值出现在土壤贮水量亏损期。(4)在梭梭生长季,梭梭群落累积蒸散量增幅始终高于累积降雨量增幅,累积蒸散量大于累积降雨量。  相似文献   
254.
荒漠土壤微生物群落结构特征研究进展   总被引:3,自引:2,他引:1  
李婷  张威  刘光琇  陈拓 《中国沙漠》2018,38(2):329-338
荒漠生态系统占地球陆地面积三分之一,是地球化学循环中的重要部分。荒漠干旱高温、缺乏植被、UV辐射强,曾被认为是没有生命的地方。然而在这恶劣环境中却蕴含有大量的微生物资源,尤其是荒漠土壤富集了大量微生物。微生物参与和主导整个荒漠生态系统地球生物化学循环,对于调节重要生态过程、修复和稳定荒漠生态系统起到重要作用,对其的研究生态学意义突出。本文综述了国内外对荒漠土壤微生物群落结构特征、群落功能多样性以及微生物群落、微生物与植物、微生物与环境之间相互关系的研究现状,旨在充分了解荒漠土壤微生物多样性研究,总结对荒漠微生物生态认识的不足,为荒漠微生物生态研究方向提供参考。  相似文献   
255.
Geographers have increasingly adopted community-based learning and research into their teaching and scholarly activities since Bunge and Harvey called for an applied public geography that is both useful and challenges societal inequalities. With few exceptions, however, there has been little discussion of methods for measuring this work. Many published assessments focus on the impacts of projects on students but overlook the impacts on community partners. Impacts on faculty and the larger university community are also often ignored. This article discusses literature on the evaluation of community–university research and service learning from a critical perspective. A discussion of service learning and community-based research (CBR) projects at two Chicago universities, DePaul and Chicago State, is presented. In both cases challenges were encountered to achieve full evaluation of projects, yet both included an evaluation of university and community partners that allowed for assessment of the projects’ value to all partners.  相似文献   
256.
Unimpeded trade is one of the cooperation priorities in the Belt and Road Initiative proposed by China. On 15 May 2017, the Joint Communique of the Leaders Roundtable of the Belt and Road Forum for International Cooperation reaffirmed the participants’ shared commitment to build an open economy and ensure free and inclusive trade. The Belt and Road Initiative (BRI) is not only China's new action to drive its open and global development, but also a platform for an increasing number of countries to explore free and inclusive trade and promote a universal, rule-based, open, non-discriminatory, and equitable multilateral trade system. It is therefore important to examine the topological relationship between the BRI and global trade networks. More specifically, this article first analyzes the community structure of trade networks using a community detection algorithm, and then estimates the topological relationship between different trade communities. The findings of this article are as follows. First, this research identified three trade communities and two sub-communities in the BRI trade network, in which China is the core, Russia is the sub-core of the biggest trade community, and India, United Arab Emirates, and Saudi Arabia are cores of the second trade community (South Asia-West Asia). Second, it identified five trade communities in the global trade network, centred on China, USA, Russia, India-United Arab Emirates, and Germany- Netherlands-France-Britain and other European developed countries. Third, the topological analysis indicated that in the global trade network, most BRI countries are attracted by the core nodes of the BRI regions, such as the China, Russia and India-United Arab Emirates core nodes, and have strong trade contacts with BRI countries. Most Central-East European countries are mainly attracted by Germany-Netherlands-France-Britain and other developed European countries with a low penetration of BRI trade. Although some Southeast Asian countries are incorporated into the Asia-Australia-South Africa community with China as the core, they still need to strengthen trade linkages with BRI countries.  相似文献   
257.
This article engages with the coproduction of urban space by focusing on a slum upgrading project in Recife, Brazil. It argues that the urban situation is essentially inconsistent, unpredictable and unstable. It documents the history of urban planning in Recife, paying special attention to the coexistence of two different planning traditions, one aimed at what city planners call the informal city, which is participatory, bottom up and democratic, yet susceptible to be corrupted by political clientelism, and another aimed at the formal city, which is ‘strategic’, top down, technocratic and neoliberal. It argues that the informal/formal binary operates as a disjunctive synthesis that separates social actors rather than connecting them and provides the coordinates within which processes of coproduction take place. The disjunctive synthesis renders possible all sorts of fantastic imaginations that both disavow and reveal the missing ground of the city. Community leaders play a central role in the coproduction of urban space and function as the symptom of this absent ground. The article concludes that participatory urban development interventions aiming to curtail the role of community leaders end up as veritable tyrannies of participation, which should be seen as evidence of the disjointed character of planning rather than as forms of effective governmentality.  相似文献   
258.
This study examines the eminent domain action in 1942 where the federal government took 411 acres of land, including an African American neighborhood, to construct the Pentagon building in Arlington County, Virginia. The Fifth Amendment of the U.S. Constitution acknowledges the right of the federal government to exercise eminent domain where needed for the common good, but requires that property owners be given just compensation. This study explores the issue of compensation: what the residents lost when they were forced to move, how that loss was compensated, and whether the compensation was “just.” The study data include interviews with former residents of the neighborhood, oral histories, land records, census data, photographs, and newspaper articles. The study concludes that the federal government compensated the residents for land and buildings, but was unable to compensate for a lost community. For many residents, that community is mourned even 72 years later.  相似文献   
259.
陈卉  甄峰 《地理科学进展》2016,35(9):1167-1176
在中国老龄化进程加快以及智慧养老快速发展的背景下,如何运用信息通讯技术(ICT)提高老年人社区生活质量成为地理学与规划学等领域的关注热点。本文选取南京市首个智慧平台落户社区——锁金社区为实证调研对象,通过构建结构方程模型结合问卷调查,探究信息通讯技术对老年人的社区满意度影响路径,其中问卷内容主要包括个人特征属性、个人ICT使用情况、社会支持情况、社区满意度等。结果表明:老年人信息设备的拥有及使用越趋向多元化,其网络活动越频繁;受教育使用水平越高、使用互联网意愿更强烈的老年人其网络活动越频繁;信息通讯技术主要通过社交类网络活动促进老年人的家庭、邻里交往,提高老年人的社会支持,从而提升社区满意度;与社区建成环境相比,社会支持对于老年人的社区满意度影响更大。因此,合理运用信息通讯技术加强老年人与家人、邻里等的联系强度,是提高老年人社区生活质量的一条可行路径。研究结果对于智慧社区、智慧养老建设具有一定的借鉴意义。  相似文献   
260.
基于SNA的新型集中社区公共空间网络结构优化   总被引:2,自引:2,他引:0  
公共空间并非“存在即合理”。公共空间网络结构效率折射出社会网络的重构能力、社会资本的建构强度、社会秩序的重塑能力。新型集中社区作为近年大量涌现的新型居住形态,正面临社会关系重构的巨大压力。本文运用社会学的网络分析法研究公共空间网络,并对苏州新型集中社区D的公共空间网络结构进行实证分析,其结论为:公共空间网络的关联度为0.216、中心势0.358、小世界值1.978,表明空间网络整体关联度不足,呈现出破碎化的特征;商业空间整合效应的发挥受到业态配置的影响;居民社会属性对空间网络结构特征造成一定影响。最后,基于“社会—空间”互动逻辑,以社会网络重构为导向,从集中安置模式、公共空间网络优化2个层面,提出新型集中社区有待进一步研究的方向,以期为当前及未来的集中社区规划建设和公共空间整体优化提供科学合理的依据。  相似文献   
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