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21.
Rapid flood mapping is critical for local authorities and emergency responders to identify areas in need of immediate attention. However, traditional data collection practices such as remote sensing and field surveying often fail to offer timely information during or right after a flooding event. Social media such as Twitter have emerged as a new data source for disaster management and flood mapping. Using the 2015 South Carolina floods as the study case, this paper introduces a novel approach to mapping the flood in near real time by leveraging Twitter data in geospatial processes. Specifically, in this study, we first analyzed the spatiotemporal patterns of flood-related tweets using quantitative methods to better understand how Twitter activity is related to flood phenomena. Then, a kernel-based flood mapping model was developed to map the flooding possibility for the study area based on the water height points derived from tweets and stream gauges. The identified patterns of Twitter activity were used to assign the weights of flood model parameters. The feasibility and accuracy of the model was evaluated by comparing the model output with official inundation maps. Results show that the proposed approach could provide a consistent and comparable estimation of the flood situation in near real time, which is essential for improving the situational awareness during a flooding event to support decision-making. 相似文献
22.
Flood management and adaptation are important elements in sustaining farming production in the Vietnamese Mekong Delta (VMD). While over the past decades hydraulic development introduced by the central government has substantially benefited the rural economy, it has simultaneously caused multiple barriers to rural adaptation. We investigate the relational practices (i.e., learning interactions) taking place within and across the flood management and adaptation boundaries from the perspective of social learning. We explore whether and how adaptive knowledge (i.e., experimental and experiential knowledge) derived from farmers’ everyday adaptation practices contributes to local flood management and adaptation policies in the selected areas. We collected data through nine focus groups with farmers and thirty-three interviews with government officials, environmental scientists, and farmers. Qualitative analysis suggests that such processes are largely shaped by the institutional context where the boundary is embedded. This study found that while the highly bureaucratic operation of flood management creates constraints for feedback, the more informal arrangements set in place at the local level provide flexible platforms conducive to open communication, collaborative learning, and exchange of knowledge among the different actors. This study highlights the pivotal role of shadow systems that provide space for establishing and maintaining informal interactions and relationships between social actors (e.g., interactions between farmers and extension officials) in stimulating and influencing, from the bottom-up, the emergence of adaptive knowledge about flood management and adaptation in a local context. 相似文献
23.
廊道型乡村旅游地农户生计资本评价与空间格局特征——以大别山国家风景道为例 总被引:1,自引:0,他引:1
以大别山国家风景道为例,借鉴DFID可持续生计分析框架,构建农户生计评价指标体系,分析廊道型乡村旅游地农户生计资本的空间特征及影响因素.研究发现:①大别山旅游廊道内自然资本等有形生计资本权重较高,社会资本等无形生计资本权重较低.②农户生计资本具有较为明显的空间分布不均衡的特征,各乡镇以及乡镇内各村的农户生计资本水平也存... 相似文献
24.
Rethinking small-scale fisheries compliance 总被引:3,自引:1,他引:2
Fisheries compliance has been identified as key to sustainable fisheries management. However, it has been widely acknowledged that the approach by many governments worldwide to achieve compliance is largely through law enforcement efforts. Although theories of normative action have expanded compliance thinking from that of rationalist approaches, this paper takes the argument further. By drawing on criminology and security discourse, and on empirical research on small-scale fisheries in South Africa, this paper argues for a new approach to our understanding of compliance. Furthermore, it argues that rather than taking law as given, the formation of law and the power dynamics influencing such processes are critical aspects that need to be acknowledged and understood in fisheries compliance theory. 相似文献
25.
李建新 《地球信息科学学报》2000,2(1):53-59
联邦德国议会1991年决定, 议会与政府核心部门在2000年前从波恩迁回柏林 ,波恩保留联邦行政管理中心的功能。为了按时准确地规划和完成落实迁都建设工程,在柏林建设国家行政办公设施和国家工作人员生活居住设施,解决波恩地区因国家机关迁离而遭受的损失,参加建设的许多部门应用了地球信息技术。文中介绍了“柏林房地产信息系统”,“联邦议会与政府核心区建设信息系统”,“物业管理信息系统”,“波恩地区经济地理信息系统”以及地球信息技术在交通和环境管理中的应用。 相似文献
26.
国际贸易对地区劳动力技能升级的影响——基于中国大陆地区地级市的数据分析 总被引:1,自引:1,他引:0
随着中国人口红利逐渐消失,劳动力技能升级的问题日益突出。已有研究表明,发展中国家融入全球生产网络体系并非必定能够促进劳动力技能的升级。论文以中国大陆地区主要地级市为例,利用2005、2010、2015年的面板数据,试图分析国际贸易对各地区劳动力技能结构变动及技能升级方面的影响。结果表明:出口贸易对地区高技能劳动力就业比重具有抑制作用,表现为出口贸易对劳动力技能降级的影响;而进口贸易所产生的技术扩散效应尚未显现,进出口贸易整体影响并不显著。进一步来看,从区域产业地理格局角度,对外贸易影响了不同技能水平劳动力人群的区域间流动,使得对外贸易对劳动力技能升级的影响效果在不同的区位与城市规模特征间存在显著差异。沿海城市和大城市主要表现为进口贸易显著促进高技能劳动力就业比重进而带来地区劳动力技能升级,相对于内陆地区和小城市而言,出口贸易会带来高技能劳动力就业比重下降,地区劳动力技能呈现降级趋势。 相似文献
27.
随着灾害强度、频率以及承灾体暴露的增加,自然灾害造成的损失日益严重。资本存量作为承灾体的经济暴露指标之一,是灾害损失评估的前提和基础。针对目前中国缺乏省域尺度长时间序列的经济部门分类的资本存量数据基础,论文通过永续盘存法,建立了2003—2015年中国大陆31省17部门的资本存量数据库,并分析其时空特征。结果显示:① 全国总资本存量与灾害直接损失的年际变化均呈增加趋势。省域尺度上,通过相关性分析显示,在99%置信度水平上,两者呈显著正相关(r=0.3)。② 时间上,各省17部门资本存量基本也呈增加趋势,但增速不同。在各部门增速最快的省份中,黑龙江省的居民服务、修理和其他服务业增速最快,增长约454.3倍;其次是青海省的租赁和商务服务业(398.3倍)、江苏省的金融业(295.1倍)、安徽省的科学研究和技术服务业(125.1倍)等。③ 空间上,2015年各省17部门资本存量最多的前4个部门分别是房地产业,工业,交通运输、仓储和邮政业,水利、环境和公共设施管理业,占比均在60%以上;且这4个部门资本存量暴露最多的省份是江苏省和广东省。该结果有助于从时空角度了解各省各部门资本存量暴露情况,为各省灾害风险管理者的防灾减灾工作提供重要的参考价值。 相似文献
28.
William B. Meyer 《Geographical review》2019,109(1):131-145
The phenomenon of urban primacy has been much studied in the social sciences since Mark Jefferson introduced the term in 1939. It is less well recognized that many European and American writers of stature from the late seventeenth century onward had discussed the same phenomenon under other names, often that of a “capital” or its cognates in other languages. Their work attests to the wide currency that the concept enjoyed and offered many important suggestions regarding urban primacy's causes and consequences. Jefferson nonetheless remains a central figure in the history of the idea for having inaugurated the coordinated academic study of the topic. 相似文献
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