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261.
In response to extreme events, researchers have recognised the convergence of volunteers, emergency responders, and other individuals and organisations. In 2000, geographer Paul Routledge presented the concept of convergence spaces as a theoretical means to explain social movements. In applying this concept, this paper explores the geographic space in which organisations and individuals converged immediately following the 11 September 2001 attacks on the World Trade Center. The paper begins to answer the question of whether there were in fact any patterns of convergence among the locations utilised by organisations responding to the attacks. Using data collected from field documents, these geographic locations are mapped over 12 days to help identify possible patterns of clustering. Results of this analysis will begin to provide researchers, policy makers and practitioners with a better understanding of how emergency response evolves geographically following an event.  相似文献   
262.
Abstract: Determining the permeability of different types of landscape matrices to animal movement is essential for conserving populations in fragmented landscapes. We evaluated the effects of habitat patch size and matrix type on diversity, isolation, and dispersal of ithomiine butterflies in forest fragments surrounded by coffee agroecosystems in the Colombian Andes. Because ithomiines prefer a shaded understory, we expected the highest diversity and abundance in large fragments surrounded by shade coffee and the lowest in small fragments surrounded by sun coffee. We also thought shade coffee would favor butterfly dispersal and immigration into forest patches. We marked 9675 butterflies of 39 species in 12 forest patches over a year. Microclimate conditions were more similar to the forest interior in the shade‐coffee matrix than in the sun‐coffee matrix, but patch size and matrix type did not affect species richness and abundance in forest fragments. Furthermore, age structure and temporal recruitment patterns of the butterfly community were similar in all fragments, independent of patch size or matrix type. There were no differences in the numbers of butterflies flying in the matrices at two distances from the forest patch, but their behavior differed. Flight in the sun‐coffee matrix was rapid and directional, whereas butterflies in shade‐coffee matrix flew slowly. Seven out of 130 recaptured butterflies immigrated into patches in the shade‐coffee matrix, and one immigrated into a patch surrounded by sun coffee. Although the shade‐coffee matrix facilitated movement in the landscape, sun‐coffee matrix was not impermeable to butterflies. Ithomiines exhibited behavioral plasticity in habitat use and high mobility. These traits favor their persistence in heterogeneous landscapes, opening opportunities for their conservation. Understanding the dynamics and resource requirements of different organisms in rural landscapes is critical for identifying management options that address both animals’ and farmers’ needs.  相似文献   
263.
Abstract:  Plantation forests and second-growth forests are becoming dominant components of many tropical forest landscapes. Yet there is little information available concerning the consequences of different forestry options for biodiversity conservation in the tropics. We sampled the leaf-litter herpetofauna of primary, secondary, and Eucalyptus plantation forests in the Jari River area of northeastern Brazilian Amazonia. We used four complementary sampling techniques, combined samples from 2 consecutive years, and collected 1739 leaf-litter amphibians (23 species) and 1937 lizards (30 species). We analyzed the data for differences among forest types regarding patterns of alpha and beta diversity, species-abundance distributions, and community structure. Primary rainforest harbored significantly more species, but supported a similar abundance of amphibians and lizards compared with adjacent areas of second-growth forest or plantations. Plantation forests were dominated by wide-ranging habitat generalists. Secondary forest faunas contained a number of species characteristic of primary forest habitat. Amphibian communities in secondary forests and Eucalyptus plantations formed a nested subset of primary forest species, whereas the species composition of the lizard community in plantations was distinct, and was dominated by open-area species. Although plantation forests are relatively impoverished, naturally regenerating forests can help mitigate some negative effects of deforestation for herpetofauna. Nevertheless, secondary forest does not provide a substitute for primary forest, and in the absence of further evidence from older successional stands, we caution against the optimistic claim that natural forest regeneration in abandoned lands will provide refuge for the many species that are currently threatened by deforestation .  相似文献   
264.
钱悦  许彬  夏玲君  陈燕玲  邓力琛  王欢  张根 《环境科学》2021,42(5):2190-2201
利用2016~2019年生态环境部环境监测总站提供的江西省11个设区市的监测数据及同期的国家气象观测站常规观测资料,研究江西省臭氧污染特征与气象因子的关系.结果表明,江西省近几年臭氧污染日益严重,2016年全省臭氧(日最大8 h滑动平均值)平均浓度为80.1 μg·m-3,到2019年上升至98.2 μg·m-3,平均年增长率为6 μg·m-3.2019年江西省11个设区市O3超标总天数为475 d,占总超标天数的72.6%.2016~2018年O3月平均浓度具有典型的季节变化特征:夏季 > 春季 > 秋季 > 冬季,2019年秋季由于降水量显著减少、日照时数增多和气温升高等气象条件导致秋季近地面臭氧浓度异常升高,其平均浓度高于其它季节.臭氧浓度总体与气温、日照时数呈正相关,与相对湿度呈负相关,当气温高于30℃、相对湿度在20%~40%区间、风速在2~3 m·s-1区间时易出现高浓度臭氧污染.江西省臭氧浓度呈现一定的空间分布特征:赣东北地区低于其他地区,南部城市高于北部城市.其中,赣州市臭氧污染较为严重,其2019年平均浓度居全省最高,为104.2 μg·m-3.基于后向轨迹HYSPLIT模型和潜在源解析PSCF对赣州市进行分析,研究结果表明赣州市臭氧污染的主要潜在贡献源区存在一定的季节差异:春季臭氧污染的外来输送源主要来自广东中部和江西北部地区,夏季主要来自江西北部地区,而秋季则主要来自广东北部和安徽中部地区.  相似文献   
265.
选取2000~2010年为时间断面,以江西省为研究对象,利用第五、第六次人口普查数据和统计年鉴,结合Arcgis、Geoda、SPSS软件和主成分分析、回归分析等方法,测算文化素质指数,分析人口文化素质概况并研究其空间格局演变,从赣北、赣中、赣南三大区域和地级市两大角度分析人口文化 城市匹配程度。研究发现:(1)人口文化素质指数在空间上以低低聚集为主,高素质人口仍聚集在赣北地区;(2)文化 城市偏移状况得到改善,由区域差异较大向均衡发展;(3)赣北、赣中、赣南三大区域均属于文化主导,其中赣北地区文化 城市逐渐匹配,赣中、赣南地区偏离度增加,文化主导加剧;地级市匹配状态总体较好,3种类型均有分布  相似文献   
266.
市场经济条件下江西农业资源的综合开发   总被引:2,自引:0,他引:2  
本文简述了市场经济的基本特征及其对农业资源综合开发提出的新要求,分析了目前江西农业资源开发利用中存在的问题,提出了在社会主义市场经济体制条件下,综合开发江西农业资源,发展高产优质高效农业应遵循的原则及应采取的对策和措施。  相似文献   
267.
The capital allowance structure for mining projects in developing countries affects the supply price of investment by determining the payback period, reinvestment and the timing of government receipts. Using the capital allowance structures of Sierra Leone, Tanzania, Zambia, Botswana, Papua New Guinea and Malaysia, the article develops a financial model and examines the effect of capital allowances on foreign investor and host government cash flows under various cost-price conditions. The study stresses the importance to governments of making accelerated depreciation a flexible tool to trade off against other elements in the fiscal package. From the government viewpoint, faster write-offs of capital are preferable to a tax holiday. The article places particular emphasis on evaluating the relationship between capital allowances, income tax and a rent resource tax.  相似文献   
268.
简要介绍了2005年1月17日-22日在日本神户召开的世界减灾大会的基本内容,并着重论述了当前国际减灾领域的重要进展和发展趋向,就减灾与可持续发展作了系统的论证,提出了我国减灾领域近期发展的主要方向.从世界减灾大会的各项议程和各类论坛可以看出,未来世界减灾的战略可以概括如下:加强减灾能力建设是促进区域可持续发展的核心任务,全面推进社区减灾体系的建设是实现未来10年减灾目标的关键任务;建立与灾害风险共存的经济与社会体系,必须把减灾与区域发展有机地整合起来,寻求除害与兴利并举的可持续发展模式,建设接受一定风险水平的安全社区体系;重视包括全球气候变化、经济全球化、世界城镇化等自然与人文过程引发或孕育的新的灾害风险;建立满足区域减灾目标需要的预警系统,加强减灾信息共享,充分利用现有的减灾资源.针对国际减灾发展趋向,提出了中国减灾战略调整的建议,即实施"区域减灾"、"综合减灾"、"科教减灾"、"提高区域减灾能力"和"加强减灾科技能力建设".  相似文献   
269.
基于中国出口产品在国际贸易摩擦中的风险研究   总被引:3,自引:3,他引:0  
进入21世纪以来,国际贸易摩擦已成为各国经济发展中难以避免的问题,随着中国在国际贸易领域中的迅速发展,中国与其他国家的贸易摩擦也不断出现,为此所承担的风险也越来越大。笔者对中国在国际贸易中出现的摩擦的表象成因进行了认真、深刻的分析,从8个方面提出了中国防范国际贸易摩擦风险的对策:行使世贸组织赋予的权利,处理多种贸易纠纷;完善我国对外贸易法律体制,建立合乎国际惯例的贸易救济体系;建立产业投资损害预警机制,减少因盲目投资带来的风险损失;加大技术开发力度,促进产业升级与产品档次的提高;转变政府职能,运用国际惯例调控贸易经济;企业练好国际市场竞争的内功,提高防范贸易摩擦风险的能力;强化行业协会职能,协调对内、对外关系;慎重处理好人民币汇率升值与汇率机制问题。同时,就中国出口产品在国际贸易摩擦中应注意的问题,也提出了尽快制定《反垄断法》、积极参与国际多边谈判等4个方面的建议。  相似文献   
270.
This article discusses the development of corporate social responsibility (CSR) in Brazil from the perspective of the Ethos Institute of Business and Social Responsibility. The Institute is a not‐for‐profit, non‐governmental organization, that has played a leading role in the Brazilian CSR effort. In Brazil, CSR initiatives have a long tradition of philanthropy, a consequence of the country's great social inequalities. The increased attention to corporate social responsibility has paralleled growing concern about sustainable development and the intensifying activities of pressure groups (consumers, customers, investors, NGOs, labour unions, the media, among others) that have been increasing since the 1990s as natural resources are progressively becoming exhausted, social tensions rising and environmental conditions deteriorating worldwide. This article identifies problems and obstacles to the growth of corporate social responsibility in Brazil, as well as advances and alternatives for CSR and towards creating conditions for the country to be internationally competitive and sustainable in the financial, social and environmental areas.  相似文献   
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