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91.
全球气候变化及快速城市化增加了极端天气事件的发生频率,高温热浪作为其中的典型效应,增加了与热相关的健康风险,越来越受到气象学、医学与地理学学者的关注。论文系统梳理了高温热浪的定义,从地理学视角,以空间评估作为切入点,总结分析了高温热浪脆弱性评估中的空间指标、空间制图方法与空间对策等方面的研究进展,指明该领域已从单一视角逐步深入到气象学、医学、地理学等复合学科的交叉研究,地理学作为桥梁将气象学与医学有机结合,为脆弱性评估提供空间指标参数、为制图提供思路与方法,并提供空间对策连接规划和风险预警等实践工作。未来的研究展望包括:空间指标综合各学科研究需要、集成各学科优势进行构建,空间制图在社区小尺度到区域大尺度的耦合机理分析基础上探讨跨区域研究表达方式,空间对策针对不同风险人群采取差异化研究,为城市适应气候变化提供科学依据。 相似文献
92.
《The Journal of geography》2012,111(4):170-176
Abstract Project Marco Polo provided the opportunity for teachers and students to experience Egypt and the eastern Mediterranean firsthand through the lens of a geographer, archeologist, and oceanographer. The National Geographic Society and U.S. Navy collaborated to provide meaningful applied geography field experiences for teacher and student participants. In addition, participants developed a global perspective which enabled them to better understand the interrelationship of the region's diverse cultures and lands. 相似文献
93.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):191-201
Carlsson, E. & Dale, B. 2011. Internationalization of knowledge-intensive SMEs: The case of petroleum-related suppliers. Norsk Geografisk Tidsskrift–Norwegian Journal of Geography Vol. 65, 191–201. ISSN 0029-1951. The internationalization of the knowledge-intensive industries, which predominantly consist of SMEs, has received increased attention recently. However, the existing body of theories of internationalization is not adequate for our understanding of multifaceted knowledge-intensive industries. The authors aim to shed light on knowledge-intensive SMEs’ internationalization and thereafter to illuminate recent theories with a relational perspective on firms and discuss their fruitfulness regarding the internationalization of SMEs of this type. Empirical data are drawn from a case study of 10 Norwegian firms, located in Trondheim, that are connected to the petroleum industry through subcontracting technology and services. The study indicates that the firms based their internationalization processes on a complex mix of modes or strategies, none of which were mutually exclusive. Planned strategies as well as coincidental processes and events seem to have influenced the internationalization decisions. It is argued that in order to understand the contingencies that may affect the process of internationalization, the concept of ‘preactivity’ may be a useful addition to the more well-known concepts of ‘reactive’ and ‘proactive’ strategies. Moreover, it is demonstrated that a relational approach is fruitful in order to understand internationalization processes among knowledge-intensive SMEs. 相似文献
94.
95.
西洋坂金矿16个矿(化)体均产于其矿源层葛坑组变质岩中,属变质热液型,根据地层、构造、土壤地球化学异常分析,区内北东、北西向断裂交汇处及其深部有找到新的金矿前景。 相似文献
96.
武夷山仙店—浦城渔梁逆冲构造带发育于崇安火山盆地东缘,呈北东向展布,由盆缘逆断层为主体,局部具推覆特征。断裂下盘以中新生代中酸性火山岩系为主,上盘主要分布前震旦系变质岩系和南北向中酸性侵入岩,构造性质与地层岩性的差异导致其成矿作用不同,逆冲断裂与火山岩系控制铀成矿作用,推覆构造与变质岩系影响铅锌多金属成矿作用。 相似文献
97.
通过综合分析平和席坑一带1∶1万土壤测量综合异常地球化学特征,及其成矿地质背景,认为平和席坑一带具有良好的锡钼铜矿找矿远景。 相似文献
98.
In Puget Sound, WA (USA), rockfish (Sebastes spp.) have significantly declined in abundance, with multiple petitions to list individual species under the Endangered Species Act. In order to better understand the ecological legacy of rockfish fishing to the Puget Sound ecosystem, the local history of rockfish exploitation was reviewed, focusing on the socioeconomic forces and management decisions which influenced the trajectory of landings. Rockfish have always been harvested for human consumption in the region, but over time exploitation patterns have changed from an opportunistic subsistence activity by indigenous peoples, to a year-round target of commercial and recreational interests. Annual commercial and recreational harvests together peaked (almost 400 mt) in the early 1980s as anglers’ attitudes changed, gear technology improved, rockfish became more familiar to the market, human population increased, and agency programs promoted fisheries to sustain employment. Rockfishes were generally not managed intensely or with conservation goals in mind until the late 1980s, in part due to scientific shortcomings and a lack of resources. By the time management actions were deemed necessary, the greatest harvest had already occurred. However, the low intrinsic productivity of most rockfish species suggests that the legacy of fishing will remain for years to come. As managers strive to restore the integrity and resilience of Puget Sound, they must realize the significance of historical fishery removals to the ecosystem and use the proper social and economic incentives to drive individual behavior toward these ecosystem goals. 相似文献
99.
南京市矿山尾矿资源与开发利用初探 总被引:1,自引:0,他引:1
多年来,尾矿一直成为一些矿山的固体废品,并造成环境污染和成为灾害隐患。合理开发利用尾矿资源,可治理环境,变废为宝,分析了南京地区的尾矿资源及开发利用情况,并就快开发利用南京的尾矿资源提出了措施。 相似文献
100.
ABSTRACTGrowth in water use and threatened shortages of water have become increasingly important in the modern world system. Natural resources are exploited extensively by capitalist interests in industrially advanced nations, while the lower strata of the world system, the underdeveloped societies, are left with limited access to natural resources for their productive processes, particularly water resources. We contribute to socio-hydrological research by examining underlying socio-structural factors that play a part in the process of deteriorating conditions of global water resources. Drawing on a world-systems perspective, this study examines how socio-structural forces – world-system position, per capita beef consumption, per capita energy consumption, and urbanization – affect per capita water footprint, which includes an accounting of “virtual water” consumption. We find that per capita beef consumption and per capita energy consumption have significant positive direct effects, and the world-system position has a significant indirect and total effect on per capita water footprint. 相似文献