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621.
基于空间聚类分析的福建省各县市经济发展水平研究   总被引:2,自引:0,他引:2  
陈小瑜  余明 《热带地理》2007,27(4):343-347
将空间坐标和属性特征有机地结合起来,给出空间距离的定义,提出位置与属性一体化的空间聚类方法——基于空间距离的K-均值聚类法,利用M atlab编写其算法程序。同时以福建省各县市经济发展水平的类型划分作为研究实例,首先选取反映社会经济发展水平的8项指标,并利用G IS技术提取各县市的重心位置坐标,再利用该空间聚类算法将福建省各县市的经济发展水平聚类为5类,结果表明此算法能够综合考虑空间位置邻近性和属性特征相似性的聚类要求,对福建区域可持续发展有一定的指导意义。  相似文献   
622.
This paper presents a framework for assessing the economic impact of disruption in transportation that can relate the physical damage to transportation networks to economic losses. A spatial computable general equilibrium (SCGE) model is formulated and then integrated with a transportation model that can estimate the traffic volumes of freight and passengers. Economic equilibrium under a disruption in the transportation network is computed subject to the condition that the adjustment of labor and capital inputs is restricted; the model reflects slow adjustment of these linked to the state of recovery. As a case study, the model reviews the large Niigata-Chuetsu earthquake of 2004. Considering the damage to the transportation infrastructure, the model indicates the extent of the economic losses arising from the earthquake distributed over regions as a consequence of the intra- and interregional trade in a regional economy. The results show that 20% of the indirect losses occur in the Niigata region directly affected by the earthquake, whereas 40% of the total losses are experienced in the Kanto region and non-negligible losses reach rather remote zones of the country such as Okinawa.  相似文献   
623.
将科技创新分解为技术研发和成果转化2个阶段,运用SUPER-SBM模型对丝绸之路经济带沿线省份科技创新效率进行综合评价,并选用面板Tobit模型对技术研发效率和成果转化效率影响因素进行分析。结果表明:总体上,丝绸之路经济带沿线各省份科技创新效率不断提升,但不同省份之间在科技创新的不同阶段效率差距较大。劳动者素质对技术研发效率的提高有显著正向影响,对成果转化效率影响不显著;对外开放对技术研发效率有显著正向影响,而对成果转化效率有显著负向影响;政府支持对技术研发效率影响不显著,对成果转化效率有显著正向影响;产业结构、基础设施对技术研发效率和成果转化效率影响均不显著。  相似文献   
624.
In Amazonia, our knowledge of the trade-offs and possible thresholds in the relationships among social, economic and environmental parameters remains quite limited and hinders the design of sustainable socio-environmental systems. To fill this gap, we analyzed relationships among landscape metrics, socio-economic patterns, biodiversity and soil-based ecosystem services within a total of 51 farms located at 6 sites of the Colombian and Brazilian Amazon. Farms were representative of an initial set of 274 and they represented colonization ages from 10 to 80 years and a range of public policies found in the region.Cluster analysis separated farms in 7 types of production systems according to 5 main criteria (size of the farm, human capital, incomes, farm products and production intensity) selected from an initial set of 18 criteria. Biodiversity was summarized into a composite index Bd built with data from 8 different groups: trees, shrubs, grasses and forbs, birds, Saturnidae and Sphingidae moths, Drosophilidae, earthworms and ants. Provision of ecosystem services was quantified by a composite indicator of 6 sub-indicators of soil hydrological functions, C storage and chemical fertility. Increasing intensity of production systems was linked to a significant decrease of indicators of natural capital biodiversity (Bd) and soil based ecosystem services (Es) with 20% and 37.3% variance explained, respectively. No relationship was observed between production systems and an indicator of human wellbeing (Sb) based on a set of 5 criteria identified with the farmers. Findings indicate that early colonizers migrate when a certain level of development has been achieved (as a result of their activities) and are replaced by wealthier populations.An overall indicator of sustainability (Su) – that combines production efficiency (Ep), Sb, Bd and Es indices (ranging from 0.1–1.0) – decreases significantly with the landscape intensification (Li) with 18.7% variance directly explained by this relationship. Su was also significantly related to production systems (36.4% variance explained): while this indicator remained relatively stable with a value of 0.5 across the early and intermediate phases following deforestation, it dropped down considerably (0.2) for production systems based on cattle ranching on highly degraded pastures with less than 2% forest cover remaining. Restoration with sylvopastoral systems allowed some farms of this former group to increase sustainability to a value of 0.35 after less than 5 years. Agroforestry systems on sites deforested at the same time maintained values around 0.5, as they allowed the maximum production efficiencies and maintained relatively high values of the Biodiversity (Bd) and Ecosystem services (Es) indexes. This is evidence that beyond the general negative trade-off between human development and natural capital observed in Amazonia, agro ecological options to revert the trend are quite promising. A general methodological approach for the reconstruction of sustainable landscapes in farms of the deforested Amazonian region is proposed as a conclusion.  相似文献   
625.
山东省烟台市牟平区辽上金矿床位于郭城断裂带东侧 ,赋存于荆山群野头组大理岩与震旦期花岗岩之接触带附近 ,矿体受NE向次级构造裂隙控制 ,呈盲矿体产出。  相似文献   
626.
The exclusive economic zone (EEZ) became accepted internationally in the 1970s. This transferred resource wealth to the coastal states establishing such zones. The history of the EEZ is reviewed, and its impact on the economic development of the Pacific island states considered. The growth performance and the tuna fishery development of these states are reviewed and possible causes of limited success discussed. The use of trust funds to increase the resource wealth of the Pacific island states is briefly considered.  相似文献   
627.
为加强对围填海开发的管理,提高围填海利用率及经济效益,基于遥感影像、统计资料与第一次全国海洋经济调查数据,文章对1990—2015年以来河北省围填海规模发展状况、产业开发特征以及围填海经济效益进行研究。结果显示,1990年以来河北省累计围填海总面积达6.21万hm2,以港口、工业和城镇建设围填海为主,围填区实体项目所涉产业主要包括农林牧渔业、交通运输与仓储业、制造业。围填海未利用面积占比达53.14%,其中计划用于制造业的围填海未利用面积较大。2015年河北省围填区域生产总值达296.23亿元,对全省GDP的贡献率达0.99%,但单位面积经济效益低于邻近省、市。分析认为,河北省围填海未利用率高、经济效益较低的主要因素包括腹地支撑程度不高、基础设施不完善、产业形势低迷及港口竞争优势不足等。当前河北省应重点从区域协同发展、区域规划、基础设施建设、优惠政策等方面加强围填海开发管理,不断优化围填海开发格局,带动沿海社会经济的发展。  相似文献   
628.
Whaling as a commercial enterprise is now defunct, not least due to the moratorium placed on it by the International Whaling Commission (IWC) almost 20 years ago. However, two distinct groups, one in favor of ‘sustainable’ whaling and one completely opposed to any killing of whales, continue to argue at the IWC and other political arenas. Almost ignored in this debate is the current growth of the whale watching industry, a logical alternative use for whale populations. Based on ecological and socio-economic criteria, the potential for whale watching is estimated for maritime countries that do not currently engage in this industry. Results suggest that whale watching could generate an additional 413 million USD (2009) in yearly revenue, supporting 5,700 jobs. Together with current global estimates, this would bring the total potential for the whale watching industry to over 2.5 billion USD in yearly revenue and about 19,000 jobs around the world. These results are discussed from an economic and conservation policy perspective, with emphasis on potential benefits and limitations.  相似文献   
629.
新疆塔什库尔干塔吉克自治县地处中巴经济走廊北段, 自古以来就是东西方文化交流的核心地带。基于地质记录和考古发现, 对该县4 000 a B.P.以来东西方文化交流与气候环境变化的关系进行了梳理与分析。结果发现, 研究区特有的地理环境和气候变化对文化发展与传播起着重要的影响,3 500 ~ 2 800 a B.P.的干旱气候对应了中巴经济走廊东西方文化交流中断, 随着气候好转, 东西方文化交流在该区域再次畅通; 2 600 ~ 2 200 a B.P.气候变干与中巴经济走廊北段文化交流再次衰落对应; 历史时期丝绸之路的兴衰与气候变化密切相关。  相似文献   
630.
渤海作为我国唯一的内海,自然资源极其丰富,渤海沿海地区有着浑厚的工业基础以及绝佳的地理优势,海洋经济发展速度十分迅猛。但随着经济的迅速发展,生态环境与开发利用之间的矛盾也日益激化,海洋资源开发强度高、利用方式粗放,陆源污染物排放总量久居不下,重点海湾环境质量未见根本好转,环境风险压力有增无减,生态环境整体形势依然严峻。文章介绍了渤海地区的发展现状,分析渤海与濑户内海的相同与不同之处,以便于借鉴日本濑户内海的治理措施以及立法经验,深刻剖析我国海洋环境保护立法的不足,并提出健全制度体系建设、完善海洋环境管理体制、调整渔业发展、提升海洋生态预警能力监测等建议,以期总结出适合我国渤海环境治理的海洋规划方案,从而挽救渤海的生态环境,恢复渤海往日的生机。  相似文献   
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