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1.
Increases in sea surface temperature have led to distributional changes in many commercially exploited fish species. These changes have already led to conflict over mackerel fisheries, arising from demand for fair resource apportionment and desire to manage the fishery sustainably. In order to develop adaptable management strategies for complex ocean fishery systems, policymakers and researchers must move beyond a reactive producer–consumer relationship to develop proactive, supportive collaborations. The history of U.S. national fisheries management is presented as an example of this transition. Building cooperative capacity over the last two centuries has lead to a more systematic understanding of the oceans, and has led to success in reducing the number of overfished stocks. Similar development of cooperation between policymakers and researchers on an international scale may be the surest way to develop management strategies adaptable enough to withstand challenges posed by future climate change.  相似文献   

2.
The United States, Russia and China are militarily and economically among the most powerful countries in the post-Cold War period, and the interactions between the three powers heavily influence the international system. However, different conclusions about this question are generally made by researchers through qualitative analysis, and it is necessary to objectively and quantitatively investigate their interactions. Monthly-aggregated event data from the Global Data on Events, Location and Tone(GDELT) to measure cooperative and conflictual interactions between the three powers, and the complementary cumulative distribution function(CCDF) and the vector autoregression(VAR) method are utilized to investigate their interactions in two periods: January, 1991 to September, 2001, and October, 2001 to December, 2016. The results of frequencies and strengths analysis showed that: the frequencies and strengths of USA-China interactions slightly exceeded those of USA-Russia interactions and became the dominant interactions in the second period. Although that cooperation prevailed in the three dyads in two periods, the conflictual interactions between the USA and Russia tended to be more intense in the second period, mainly related to the strategic contradiction between the USA and Russia, especially in Georgia, Ukraine and Syria. The results of CCDF indicated that similar probabilities in the cooperative behaviors between the three dyads, but the differences in the probabilities of conflictual behaviors in the USA-Russia dyad showed complicated characteristic, and those between Russia and China indicated that Russia had been consistently giving China a hard time in both periods when dealing with conflict. The USA was always an essential factor in affecting the interactions between Russia and China in both periods, but China's behavior only played a limited role in influencing the interactions between the USA-Russia dyad. Our study provides quantitative insight into the direct cooperative and conflictual interactions between the three dyads since the end of the Cold War and helps to understand their interactions better.  相似文献   

3.
博弈理论在水资源管理中的应用——以黑河流域为例   总被引:2,自引:3,他引:2  
区域的地理差异使得水资源在分布上时空不均,造成水资源供给的有限性;用水主体的开发利用和效率低下使得水资源呈现过量需求,造成不必要的浪费,此两者成为了水问题产生的主要原因。博弈理论应用的目的就是通过博弈分析寻找主体之间的博弈均衡点,实现博弈主体之间的效率与利益的最大化,选出最优策略组合。本文将博弈理论应用于水问题突出的黑河流域,通过对中游地区、下游地区和流域管理局3个主体之间的博弈分析得出流域管理局的介入和中游采取合作态度成为了解决水问题实现流域可持续利用的可行性策略。为了使中游地区采取合作态度,政府可以通过制定政策与奖惩措施来控制中游地区的行为,实现流域内部的生态效益与经济效益最大化,达到区域间的合作共赢。  相似文献   

4.
While much has been written about the benefits of collaborative watershed management to address nonpoint source pollution and other water quality concerns in the United States, few scholars have addressed the catalytic nature of events that generate these collective action responses. Further, because equivalent catalyst events in different communities do not always lead to collective action, it is critical to understand the interaction between a community's baseline conditions and the catalyst events that lead to collective action. This article presents a conceptual framework that illustrates the relationship between baseline conditions and events that lead to collective action. In this article a theoretical typology of catalyst events is presented that includes both intentional and nonintentional types of events. Understanding these types of catalyst events can help water quality advocates create and/or seize opportunities to nurture a collective action. This article concludes with a call for future research into catalyst events.  相似文献   

5.
6.
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   

7.
本文以黄土高原泾河流域上游固原市为例,采用农户问卷调查和参与式社区评估方法,研究农户对生态系统服务认知及消费,并对两种方法认知结果进行比较分析。研究发现,农户问卷调查方法农户认知到食物供给、净化空气、净化环境、水土保持、供给洁净水、减少自然灾害、提高收入、薪柴供给、景观愉悦、牧草供给和防风固沙11项生态系统服务,农户日常对生态系统服务的占有和消耗及生态系统服务对农户的重要性程度影响农户对生态系统服务的认知;参与式社区评估(PRA)方法农户可以充分进行信息交流与讨论,与农户问卷调查法相比对生物多样性服务有了认知。研究区生态系统服务发生很大变化,食物供给和薪柴供给服务明显减弱,收入增加;受生态系统服务变化及收入水平的影响,农户食物和能源消费存在明显时空差异,总体而言,农户食物消费总量下降,大部分农户薪柴消费数量减少,农户对蔬菜、肉类、煤炭、天然气等的消费量增加。  相似文献   

8.
In the United States, legal steps have been taken to protect personal privacy, which is viewed as an individual's fundamental right. Location privacy (i.e., protection of personal and location information), however, has not received equal attention in the legal system. Given the recent popularity of location-based services (e.g., cell phones), it is possible to obtain an individual's location information easily and precisely. An investigation of public perception of privacy in the United States indicated that survey responders (1) were unaware of legal implications of location privacy violation and (2) believed that there should be location privacy protection similar to that provided by the Health Insurance Portability and Accountability Act and the Family Educational Rights and Privacy Act.  相似文献   

9.
《Urban geography》2013,34(3):213-236
Community networks help build place-based community by offering individual citizens and organizations access to the Internet, the ability to post information online, and opportunities to discuss community affairs. Community networks are inspired by a dynamic vision of community that incorporates a global sense of place. A global sense of place is valuable because it helps to illuminate a place's connections with the world and may therefore enable scale-jumping forms of activism. This article analyzes interviews with participants in four U.S. community networks to explore how networks combine a politics of mobility, a politics of access, and a politics of place to construct a global sense of place. The degree to which each network emphasizes mobility, access, and place varies. This variation has implications for both community activism and issues of diversity in community. Networks that fail to link mobility, access, and place may increase, rather than decrease, inequalities in access to electronic communications as well as to forms of political power.  相似文献   

10.
王云才 《地理研究》2011,30(1):10-22
传统地域文化景观空间的破碎度研究是在借鉴自然生态空间破碎度研究的基础上,吸收破碎度研究的经验、理论、观点和方法,以整体人文生态系统为对象,将传统地域文化景观看做是人类生存与发展的地方性生境,研究传统地域文化景观的时空过程与景观格局,目的在于探讨传统地域文化景观连续性和整体性保护的模式.以浙江省诸暨市直埠镇作为典型案例,...  相似文献   

11.
以广州市城区为例,基于分形理论,借助GIS技术手段,测度广州市城区1957、1982和2008年交通网络的盒子维数。结果表明:①广州市城区路网具有明显的分形特征,不同区域的盒子维数均有不同程度的增加,城市路网覆盖度不断提高,道路密度和通达性不断增强;②根据不同时期不同行政区路网盒子维数的差异和增幅大小,把广州市城区路网发育划分为3种不同类型:成熟型(东山区、越秀区、荔湾区),发展型(黄埔区、芳村区、白云区),拓展型(海珠区、天河区);③建立不同区域盒子维数与年代的线性、指数和幂指数函数关系,经对比发现指数函数关系拟合度最好,其相关系数R2>0.8,表明广州市城区交通网络近50年来发展迅速,而且这种态势还将持续下去。  相似文献   

12.
《Urban geography》2013,34(3):217-240
An international comparative urban analysis requires an effort to reconcile not only the variables, but also the units of observation from each country. In a multivariate analysis, failure with regard to the former jeopardizes the validity of the results while failure with regard to the latter risks a priori bias in the interpretation of the results. This comparative, multivariate analysis of urban quality-of-life variables from Canada and the United States calls into question the distinctiveness of the Canadian City in the North American City debate because of such potential bias. As a point of departure from past research, not only is an attempt made to harmonize the set of urban quality-of-life variables with regard to definition, year, and geography, but also to control for the definitional, geographic, and hierarchical differences between the Canadian and U.S. urban systems. Such efforts reveal the Canadian City is indeed distinct from the U.S. City, but also distinct from the North American City, which is a regional entity encompassing Canada and the United States.  相似文献   

13.
In 1975 E. H. Rapoport described a pattern of increasing latitudinal range sizes for organisms with increasing latitude, a pattern that is now known as Rapoport's rule. The universal applicability of Rapoport's rule has been long contested, making it one of the more controversial biogeographic “rules.” This study aims to reassess the applicability of Rapoport's rule to U.S. tree species. Data presented here suggest that Rapoport's rule does indeed apply to most tree taxa within the United States, but may be taxon specific. In addition, data presented here suggest that tree range patterns consistent with Rapoport's rule in the United States are not restricted to high latitudes and are not the result of a “boundedness effect” but may be intimately linked with the glacial history and physical geography of North America. The analyses conducted here are intended to emphasize the utility of such biogeographic rules even if they are not universally applicable and should, in turn, only be considered biogeographic patterns.  相似文献   

14.
改革开放以来,中国的外商直接投资经历了从“引进来”到“走出去”的发展历程。2016与2017年,中国对外直接投资(COFDI)流量与存量先后跃升至全球第二位,由外商直接投资吸收国转变为世界主要对外直接投资国之一。在中美双方经贸合作伙伴关系持续深入背景下,美国已成为中国对外直接投资首位东道国。投资是落于具体地域的,不同尺度地域投资环境的差异性是导致中国对美直接投资时空分异的重要原因。立足于中国(投资母国)视角,以美国州内各选区为研究地域尺度,利用空间自相关等方法,对美国典型州——得克萨斯州的中国对外直接投资的时空格局与演变特征进行了探讨,同时引入面板数据计量模型对COFDI在得州内各选区间投资驱动因素进行了实证分析。结果表明:(1)得州内COFDI存量持续增长,但阶段性特征明显;(2)得州内COFDI以国有企业并购为主,且主要集中在能源产业;(3)COFDI州内集聚程度较弱,局部选区间多呈现出相异属性集聚特征;(4)市场规模、劳工人数、交通通达性、华人移民数对COFDI具有正向促进作用,劳动成本、教育水平、税率、经济密度对COFDI具有不同程度的负向作用。研究结果可为中国政府、跨国企业在...  相似文献   

15.
王娟  王柯心  杨晨 《热带地理》2021,41(4):734-745
休闲渔业是美国最受欢迎的户外活动之一,在发展过程中为美国创造了巨大的经济和社会效益,并形成多主体参与的治理机制。文章在分析美国休闲渔业发展现状的基础上,运用最邻近指数、缓冲区分析、泰森多边形和关联维数测度,对佛罗里达州休闲渔业资源分布特征进行空间分析。结果显示,美国休闲渔业形成以淡水为主、咸水为辅的发展格局,其中佛罗里达州休闲渔业资源呈现集聚式、非均衡分布特征,80%的垂钓点位于海岸线20 km以内,各垂钓点之间形成紧密的关联作用。联邦政府、地方政府、行业组织和休闲渔业参与者之间形成的多中心治理模式,能够匹配美国休闲渔业大区域分散、小区域集聚的空间分布特征,适应参与主体多样化、需求差异化的发展需要。有鉴于此,针对中国休闲渔业存在的问题,提出应通过借鉴美国“自下而上”的多中心治理机制,建设服务型政府、行业协会灵活增权以及休闲渔业企业融合创新等措施,推动中国休闲渔业科学管理和高质量发展。  相似文献   

16.
Using trade data submitted by United Nations member states from 1995 to 2013, this article contributes to understanding China's trade with Latin America. By employing and building on the TECH score methodology, this project highlights China's growing economic connectivity with nine large and important Latin American economies. The analysis conducted here shows that compared with exports originating from other, more traditional foreign investors (i.e., the United States and the European Union member states), Chinese exports to these Latin American countries—although growing in sophistication over time—are relatively less technologically sophisticated during the study period. This work clarifies that in spite of these Latin American economies being highly complementary (for their natural resources and consumer markets) to China's manufacturing-intensive economy and despite the rapid growth in bilateral and biregional trade, China's displacement of traditional foreign actors, in terms of its technology-intensive exports to the region, is not supported by the data to date.  相似文献   

17.
杨高  刘柳颖  周春山 《热带地理》2021,41(3):562-572
对21位有过广州长租公寓租赁经历的租客进行深度访谈,运用扎根理论研究方法对访谈资料进行逐级编码,基于计划行为理论分析框架构建了广州长租公寓租赁意向影响机制模型.研究表明:租客在长租公寓租赁过程中,其租赁行为会受到租赁意向的驱动,租赁意向受到租赁态度、主观规范、知觉行为控制的共同影响.租赁态度由住房情感需求、住房品牌偏好...  相似文献   

18.
以美国为例,运用矢量数据符号法、核密度估计,结合负二项回归模型,研究世界一流大学空间集聚对研发密集型企业空间布局的影响,得出以下结论:① 美国一流大学和研发密集型企业高等级集聚区主要有东北沿海大都市带、硅谷地区、芝加哥都市区和洛杉矶都市区,两者呈现高度的空间集聚性和空间匹配性。② 美国研发密集型企业偏向于选择与自身从事研发领域相关的一流学科空间集聚区进行布局。③ 美国一流大学和研发密集型企业的高值热点区集中在硅谷地区,呈半圆形辐射状,较高值热点区主要分布在东北沿海大都市带,呈带状辐射。④ 为寻求创新资源禀赋,获取知识溢出经济,共享创新基础设施,降低技术转移成本,获得创新集群优势,研发密集型企业优先选择一流大学集聚区进行空间布局。  相似文献   

19.
Migrant labor is a global phenomenon and remittances of migrant workers from non-industrial nations can play an important role in improving quality of life at family, community, and national levels. We focus on workers from Guatemala who obtain visas from the United States (US) Department of Immigration’s H-2B program that allow them to spend six or seven months a year planting and maintaining pine plantations in the southeastern US. Forestry is economically important in this region and the industry has come to depend on migrant labor. Our specific interest is how the H-2B program affects livelihood strategies of these workers, their families, and their communities. Based on primary data from 49 interviews conducted in eight Guatemalan communities, we explain motivations to engage in seasonal migration and positive changes brought about by the H-2B program in nutrition, housing, healthcare and long-term investments in agricultural lands, microenterprise development, education, and family stability.  相似文献   

20.
In the decisive stage of developing of a moderately prosperous society in all aspects, hazy weather has become a major obstacle to the further advancement of China. Therefore, improving the level and efficiency of haze governance has become essential. Based on the DPSIR model, this paper builds a haze governance level and efficiency index system using the entropy method and the super-efficiency data envelope-analysis (DEA) model to analyze the data for 31 cities in North China from 2007 to 2016. From the aspects of spatial differences and influence factors influencing the comparative analysis, the results are as follows. (1) During the investigation period, the level and efficiency of city haze governance in North China showed a trend of fluctuation and decline, with obvious stages in their characteristics. Haze governance efficiency is much higher than its level, and its mean value reaches the DEA level which indicates that it is effective. (2) A significant regional gradient difference occurs between these two aspects. The haze governance level presents a convex distribution pattern of “east low-middle high-west low”, while the haze governance efficiency presents a concave distribution pattern of “east high-middle low-west high”. (3) The regression results show that economic growth has a negative effect on both haze governance level and efficiency. By contrast, the industrial structure has a positive effect on haze governance level and efficiency, but the significance of its effect on these two is different. On this basis, policy suggestions are proposed for improving the level and efficiency of haze governance in various cities in North China.  相似文献   

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