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11.
We examined the principal effects of different information network topologies for local adaptive management of natural resources. We used computerized agents with adaptive decision algorithms with the following three fundamental constraints: (1) Complete understanding of the processes maintaining the natural resource can never be achieved, (2) agents can only learn by experimentation and information sharing, and (3) memory is limited. The agents were given the task to manage a system that had two states: one that provided high utility returns (desired) and one that provided low returns (undesired). In addition, the threshold between the states was close to the optimal return of the desired state. We found that networks of low to moderate link densities significantly increased the resilience of the utility returns. Networks of high link densities contributed to highly synchronized behavior among the agents, which caused occasional large-scale ecological crises between periods of stable and high utility returns. A constructed network involving a small set of experimenting agents was capable of combining high utility returns with high resilience, conforming to theories underlying the concept of adaptive comanagement. We conclude that (1) the ability to manage for resilience (i.e., to stay clear of the threshold leading to the undesired state as well as the ability to re-enter the desired state following a collapse) resides in the network structure and (2) in a coupled social–ecological system, the systemwide state transition occurs not because the ecological system flips into the undesired state, but because managers lose their capacity to reorganize back to the desired state. An erratum to this article can be found at .  相似文献   
12.
Theoretical arguments for using a term structure of social discount rates (SDR) that declines with the time horizon have influenced government guidelines in the US and Europe. The certainty equivalent discount rate that often underpins this guidance embodies uncertainty in the primitives of the SDR, such as growth. For distant time horizons the probability distributions of these primitives are ambiguous and the certainty equivalent itself is uncertain. Yet, if a limited set of characteristics of the unknown probability distributions can be agreed upon, ‘sharp’ upper and lower bounds can be defined for the certainty-equivalent SDR. Unfortunately, even with considerable agreement on these features, these bounds are widely spread for horizons beyond 75 years. So while estimates of the present value of intergenerational impacts, including the social cost of carbon, can be bounded in the presence of this ambiguity, they typically remain so imprecise as to provide little practical guidance.  相似文献   
13.
Dispersers are expected to assess breeding habitat quality before settlement. Although cues reflecting habitat quality are well studied, social cues have not been as well evaluated. In this paper, we studied breeding habitat selection during 3 years in a natural population of blue tits, Cyanistes caeruleus, breeding in nest-boxes. Our aim was to investigate if this species used conspecific density and/or reproductive success of con- and heterospecifics (i.e., social cues) in settlement decisions. The patterns observed were consistent with the idea that juveniles, when dispersing from their natal patches, did not react to any of the cues that we tested. In contrast, breeders that dispersed seemed to respond to both conspecific mean patch reproductive success (PRS) and breeding density of the settlement patch in the year of dispersal, their response differing according to their own reproductive success. Indeed, failed breeders moved to areas with high PRS and low density relative to source patches, while successful breeders behaved the opposite. The comparison between juveniles and adults might be modulated by the limited time available to juveniles to gather information on PRS and density at the end of the dispersing year. Adults lacking these time constraints, however, seemed to rely on these conspecific cues although limited by their own quality. Additionally, breeders were more likely to be immigrants in patches with relatively low breeding success and density the previous year, suggesting that settlement is influenced by multiple cues, which may reveal information on different aspects of habitat and be available at different moments. Collectively, our results support the importance of social cues for blue tits’ settlement.  相似文献   
14.
All member states of the EU have had to develop climate strategies following the commitment to the UN Framework Convention on Climate Change and the Kyoto Protocol. The evolution of the strategies provides insights into the learning that takes place at the level of policy development and offers material for analysing how ex ante and ex post evaluations have contributed to this learning. In the analysis, Finland is used as a case demonstrating different levels and types of learning, from deeper reframing to political learning. The results show that the full potential of the evaluations has not been utilised, partly because they have been constrained by their mandate. Greater openness and transparency in the policy processes would create favourable conditions for independent evaluations that could provide additional input to the policy processes. This would support social and reflexive learning and allow for greater adaptability.  相似文献   
15.
Biomass is one of the renewable energy sources on which policy makers are greatly dependent on since it is a flexible feedstock capable of conversion into electricity, transport liquid fuels and heat by chemical and biological processes on demand. Though numerous publications have examined the relationship of economic growth with renewable energy and other parameters, biomass energy has never been included in these studies. Then, this study examines the causal relationship within a multivariate panel cointegration/error correction framework which combines the cross-section and time series data while allowing for heterogeneity across different provinces. After employing panel data regression model ranging from 2003 through 2012 to examine the relationships of biofuels production with sustainable development in China, the paper concludes that the development of biofuel energy production integrated with the consideration of the improvement of income per capita, and the attraction of more capital investment, does make a significant contribution to economic growth. However, some negative side effects including the increase of greenhouse emissions and the decrease of marginal land still coexist with the economic development. Of course, the importance of these findings lies on their implications and their adoption on strategic policies.  相似文献   
16.
We develop a landscape stewardship classification which distinguishes between farmers’ understanding of landscape stewardship, their landscape values, and land management actions. Forty semi-structured interviews were conducted with small-holder (<5 acres), medium-holders (5–100 acres), and large-holders (>100 acres) in South-West Devon, UK. Thematic analysis revealed four types of stewardship understandings: (1) an environmental frame which emphasized the farmers’ role in conserving or restoring wildlife; (2) a primary production frame which emphasized the farmers’ role in taking care of primary production assets; (3) a holistic frame focusing on farmers’ role as a conservationist, primary producer, and manager of a range of landscape values, and; (4) an instrumental frame focusing on the financial benefits associated with compliance with agri-environmental schemes. We compare the landscape values and land management actions that emerged across stewardship types, and discuss the global implications of the landscape stewardship classification for the engagement of farmers in landscape management.  相似文献   
17.
Rebecca Pearse 《环境政策》2016,25(6):1079-1101
Reporting on the origins and directions of social movement strategy on climate and energy issues in the last decade, the shifts in ‘climate movement’ practice are discussed using a neo-Polanyian account of the political economy of climate change combined with sociological analysis of the strategic decisions campaigners reported making. Since the mid-2000s, Australia’s climate movement has been engaged in three concurrent arenas of political contestation. The longest-standing arena of movement activity has been negotiations over climate policy. More recently, activists and communities are engaged in a struggle over the expansion of fossil fuels. A third contest has been waged over the present and future position of renewable energy technologies in Australia’s electricity market. In the wake of climate policy failure, energy campaigns have been deepened, and it seems that a broader energy justice agenda is being forged. New strategic dilemmas are visible in the field.  相似文献   
18.
煤炭行业清费建税,资源税从价计征引起了社会各界对资源税费制度改革的热议,而资源耗减价值是资源税费制度改革的重要依据之一。将资源回采率纳入使用者成本模型,科学计量了我国2000-2011年间煤炭资源的耗减价值。分析表明:2000-2011年间,4%折现率下煤炭资源耗减价值增加了22倍之多,而资源税费却仅仅增长了7倍,煤炭资源耗减价值与资源税费实际征收额之间存在有巨大缺口得不到补偿;国家资源所有者权益的实现度与煤炭经济形势呈逆向分布,煤炭工业利润率的上升并没有带来国家资源所有者权益的增加,导致这种错位的原因与我国不合理的资源税收机制有很大关系;资源税税率的理论区间为1.11%-8.85%,与国家规定的2%-10%高度重合,从而说明国家决策的合理性。为使资源所有者权益的实现度与煤炭工业经济形势相"挂钩",以资源税收入等于资源耗减价值为切入点,对资源所有者权益的实现度进行数理分析,求得了资源税税率与当期资源价格的关系,发现固定税率的资源税难以适应市场波动,于是提出"资源税+利润税"的组合税收工具,确定了利润税的起征点,计算得出了资源税和利润税的税率组合。该组合税制在一定程度上能够平抑经济周期对煤炭工业造成的影响,同时又维护国家资源所有者权益,从而实现国家与煤炭工业"利益共享、风险共担"。  相似文献   
19.
在可持续发展和扶贫框架下发展绿色经济与国际可持续发展制度建设及改革是当前世界可持续发展的核心和关键,也是"里约+20"峰会的两个主题。首先,绿色经济是体现经济社会与资源环境相协调和可持续发展的根本途径。绿色经济的核心是以低的自然资源消费、低排放、低污染,达到高的自然资源利用效益,实现高的经济社会发展水平,提供高的生活水平和优良的生活环境。全球绿色经济的发展潮流,将引发社会形态由"工业文明"向"生态文明"转变。虽然经济发展和消除贫困是发展中国家当前首要和压倒一切的优先任务,但也必须探索新型的绿色低碳工业化和现代化道路,在实现工业文明的过程中,努力建设生态文明,实现跨越式发展。同时积极应对全球绿色低碳转型中新的经济、贸易、技术竞争规则和格局的变动,加强先进技术创新,提升自身的低碳竞争力。其次,公平获取可持续发展的理念,应成为国际可持续发展制度建设和改革的基本原则。可持续发展要求既要促进经济社会发展与资源环境相协调,促进"代际公平",又要关注欠发达地区消除贫困,提高生活质量,改善生态环境,实现"国别公平"、"人际公平"。因此,国际可持续发展制度框架的建设和改革,要体现世界各国公平获取可持续发展的理念和原则,全面均衡地反映不同国情和发展阶段国家的利益诉求。主要表现在公平享有全球环境空间、公平获得现代优质能源服务、公平适应全球环境变化、公平承担责任义务及公平的国际制度和机制。中国需要统筹国内外两个大局,走中国特色的绿色低碳发展之路。最后,中国的国情和发展阶段特征,在可持续发展领域又面临比发达国家更多的困难和更严峻的挑战。在全球发展绿色经济,努力实现可持续发展的大背景下,中国要统筹国际国内两个大局,协调推进。在国际上积极参与国际制度的建设和改革,在促进全球经济发展,社会进步和环境保护等方面发挥积极的建设性的作用。在国内加强可持续发展战略的实施,走绿色、低碳和可持续发展的路径。主要战略对策包括加速转变发展方式,强化节能优先,控制能源消费总量和CO2排放总量的过快增长;加强能源结构的低碳化,逐步建立并形成以新能源和可再生能源为主体的可持续能源体系;加强城乡统筹,地区平衡,促进生态城市建设;适应国际可持续发展制度改革的趋势,加强绿色低碳和可持续发展的制度建设;抓住机遇,顺应世界绿色低碳发展潮流,自主实现发展方式的转变,把传统的资源依赖型、粗放扩张的发展方式转变到新型的技术创新型、内涵提高的发展方式上来,基本走上绿色低碳和可持续发展的轨道。  相似文献   
20.
This study addresses the use of message carriers to convey corporate social responsibility information to promote eco-purchasing involvement. The work tests various media formats transmitted via social media. The effects of corporate vs. peer communication in a corporate social responsibility campaign in stimulating self-reported eco-purchasing involvement are indicated. The research varies communication dimensions of a fictional corporate social responsibility campaign sent through social media. Multiple media formats; new release; article; and advertisement were tested, as was the inclusion of social media persuasive sentiment. The analysis of source/format combinations and source/format/sentiment combinations found statistically significant differences for consumer-to-consumer communication in stimulating eco-purchasing involvement in certain circumstances. This research suggests an emerging role for the consumer communicator as a content co-creator and validates the effective use of articles and news releases instead of advertising on social media, yielding managerial and scholarly implications.  相似文献   
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