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301.
Refugia-based conservation offers long-term effectiveness and minimize uncertainty on strategies for climate change adaptation. We used distribution modelling to identify climate change refugia for 617 terrestrial mammals and to quantify the role of protected areas (PAs) in providing refugia across South America. To do so, we compared species potential distribution across different scenarios of climate change, highlighting those regions likely to retain suitable climatic conditions by year 2090, and explored the proportion of refugia inside PAs. Moist tropical forests in high-elevation areas with complex topography concentrated the highest local diversity of species refugia, although regionally important refugia centers occurred elsewhere. Andean–Amazon forests contained climate change refugia for more than half of the continental species’ pool and for up to 87 species locally (17 × 17 km2 grid cell). The highlands of the southern Atlantic Forest also included megadiverse refugia for up to 76 species per cell. Almost half of the species that may find refugia in the Atlantic Forest will do so in a single region—the Serra do Mar and Serra do Espinhaço. Most of the refugia we identified, however, were not in PAs, which may contain <6% of the total area of climate change refugia, leaving 129–237 species with no refugia inside the territorial limits of PAs of any kind. Our results reveal a dismal scenario for the level of refugia protection in some of the most biodiverse regions of the world. Nonetheless, because refugia tend to be in high-elevation, topographically complex, and remote areas, with lower anthropogenic pressure, formally protecting them may require a comparatively modest investment.  相似文献   
302.
发展循环经济的国际经验和对我国的启示   总被引:20,自引:1,他引:20  
对发展循环经济的国际经验进行系统分析与研究.德国、日本等发达国家发展循环经济、建设循环型杜会的演变、动因、主要做法及其执行效果、对其他发达国家的废弃物管理措施、清洁生产和生态工业园区建设等.值得我们关注。为此.特提出国际经验对我国发展循环经济的启示.包括战略选择、法规法律、政策制度、体制与机制、优先领域、技术与信息、宣传教育与公众参与等。经过比较研究.认为我国目前要大力推进循环经济.应该借鉴国际先进经验.建立健全法律和关键制度.选择合适的优先领域.加强循环经济技术支撑体系研究.通过宣传教育提高公众意识.形成“政府引导、企业实践、公众参与。的循环经济发展机制。  相似文献   
303.
一种部分碳税机制的经济分析   总被引:3,自引:0,他引:3  
基于目前全球气候变化谈判的困境提出一种部分碳税机制,这种机制与1997年12月缔约国大会第三次会议所形成的京都议定书第12条确立的清洁发展机制(CDM)的雏形清洁发展基金(CDF)有相似的特征,即要求附件I缔约方为实现公约的目的和体现公约有区别的责任原则,通过实行统一的税收机制并将税收收入转移到发展中国家作为他们在历史过程中过多排放温室气体的自然债务的补偿  相似文献   
304.
多物种系统在农药生态效应的评估中不可或缺,有必要探索系统的建立和应用,为此笔者构建了包含隆线溞(Daphnia carinata)、中华薄壳介(Dolerocypris sinensis)和锯缘真剑水蚤(Eucyclops serrulatus) 3种节肢动物当中的1种或全部,以及包含萼花臂尾轮虫(Brachionus calyciflorus)、小球藻(Chlorella vulgaris)和轮叶黑藻(Hydrilla verticillata)的4组多物种系统。它们被用来测量杀虫剂毒死蜱的群落效应。研究结果显示,包含3种节肢动物的测试系统比只包含1种的系统中群落结构更稳定,更能够揭示杀虫剂对轮虫的诱导效应,其对杀虫剂也更敏感。毒死蜱在该系统内的最高无作用浓度(NOEC)和最低有效浓度(LOEC)分别为0.25和1.25μg·L~(-1)。本研究所构建的是一类总氮、总磷和浊度水平趋于下降的测试系统。杀虫剂的引入促进了系统内p H、铵态氮和电导率水平的上升以及总氮、总磷和浊度水平的下降。从LOEC的数值及持续时间上看,游离态壳二糖酶可以被用来指示农药对浮游动物的胁迫。本研究的结果显示,包含3种节肢动物的测试系统能够更准确地衡量农药对浮游动物的生态胁迫。  相似文献   
305.
The regulatory contribution that preferential trade agreements (PTAs) make to global climate governance is assessed through an analysis of climate-related provisions found in 688 PTAs signed between 1947 and 2016. Provisions are analyzed along four dimensions: innovation, legalization, replication, and distribution. Innovative climate provisions are found in several PTAs that are in some cases more specific and enforceable than the Kyoto Protocol and the Paris Agreement. Nonetheless, these climate provisions offer limited progress because they remain weakly ‘legalized’, fail to replicate broadly in the global trade system, and were not adopted by the largest greenhouse gas emitters. Despite the inclusion of innovative climate provisions in a number of PTAs, their poor design and weak replication position them as some of the weakest environmental provisions within PTAs.  相似文献   
306.
“一带一路”战略背景下金属产业国际产能合作研究   总被引:1,自引:0,他引:1  
随着全球经济发展放缓,金属资源国内需求结构变化,资源约束压力、产能过剩等问题更加突出。如何通过国际产能合作化解金属产业难题是亟待解决的一个现实问题。本文从中国金属产业的现状出发,借鉴美、日产能转移的成功经验,在"一带一路"战略的大背景下探索适合中国金属产业开展产能合作的新模式并提出相应的政策建议。研究认为,中国已成为世界金属生产和消费大国且工业化进入中后期,具有进行国际产能合作的现实需求,"一带一路"战略为中国金属产能国际转移带来了历史契机。这种契机主要表现在沿线国家的基础设施建设热潮带来全球金属资源消费新的增长点,中国主导的"一带一路"战略构建了一种新型地缘政治格局,既能增强中国在沿线国家中的贸易话语权,也为中国开展国际产能合作提供了条件。研究指出,在"一带一路"战略下,中国金属产业的产能转移应以"互利共赢"为基础创新产能合作模式:即以产能合作推动产能转移,达到产业互补经济互惠的目的;以产能输出取代产品输出,有效回避西方国家针对中国的"双反"政策;以基础设施援建消化部分产能,在帮助沿线国家发展基础设施建设的同时消化自身部分富余产能。在合作策略上,应注重六个方面:一是充分利用"一带一路"的战略合作关系;二是实施低端转移高端做强的策略方针;三是全方位开放和深化产能合作;四是开展境外产业园区建设和有色金属精深加工工程;五是大力鼓励民营资本参与;六是创新金属矿业投资模式。  相似文献   
307.
Land use change can significantly affect the provision of ecosystem services and the effects could be exacerbated by projected climate change. We quantify ecosystem services of bioenergy‐based land use change and estimate the potential changes of ecosystem services due to climate change projections. We considered 17 bioenergy‐based scenarios with Miscanthus, switchgrass, and corn stover as candidate bioenergy feedstock. Soil and Water Assessment Tool simulations of biomass/grain yield, hydrology, and water quality were used to quantify ecosystem services freshwater provision (FWPI), food (FPI) and fuel provision, erosion regulation (ERI), and flood regulation (FRI). Nine climate projections from Coupled Model Intercomparison Project phase‐3 were used to quantify the potential climate change variability. Overall, ecosystem services of heavily row cropped Wildcat Creek watershed were lower than St. Joseph River watershed which had more forested and perennial pasture lands. The provision of ecosystem services for both study watersheds were improved with bioenergy production scenarios. Miscanthus in marginal lands of Wildcat Creek (9% of total area) increased FWPI by 27% and ERI by 14% and decreased FPI by 12% from the baseline. For St. Joseph watershed, Miscanthus in marginal lands (18% of total area) improved FWPI by 87% and ERI by 23% while decreasing FPI by 46%. The relative impacts of land use change were considerably larger than climate change impacts in this paper. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
308.
Climate change has been considered as the most paramount global environmental problem and the biggest externality throughout the history of human development. Accordingly, the world is facing unprecedented technological innovation and collaborative demands to deal with climate change. In the 2015 Paris Agreement, a long-term vision of technology development and transfer implementation was proposed, and policy and financial support for technological innovation in the area of climate change was advocated. These terms aim to enable developing countries to acquire the necessary technology in the early stage of the technology cycle to address climate change challenge. However, the traditional technological innovation and cooperation mode based on industrial civilization can hardly meet the technical demands of global climate protection. To ensure the continuous development and deployment of technology in a required scale and pace, a new global technical cooperation system is proposed to develop based on the philosophy of ecological civilization. The core contents of this system are supposed be as follows: to implement all-win cooperation targets, adhering to cooperation principles of Eco-man, adopt cooperation content that reflects synergy, pursue cooperation based on mutual trust, encourage participation of multiple actors, and promote sharing of cooperative outputs.  相似文献   
309.
Increasing concerns about climate change have given rise to the formation of International Environmental Agreements (IEAs) as a possible solution to limit global pollution effects. In this paper, we study the stability of IEAs in a repeated game framework where we restrict to strategies which are simple and invariant to renegotiation. Our main contribution is that we characterize necessary and sufficient conditions for stability of an IEA when pollution has both a global and local effect. Local pollution spillovers are represented by a network structure. We find that stable IEAs exist if the network structure is balanced. Too large asymmetries in the degree of local spillovers may, however, lead to non-existence of stable structures. We also discuss the implications of our results for welfare. The generality of our approach allows for several applications, in particular the provision of public goods.  相似文献   
310.
We studied the multiscale (sites, river reaches and rivers) and short-term temporal (monthly) variability in a freshwater fish assemblage. We found that small-scale spatial variation and short-term temporal variability significantly influenced fish community structure in the Macquarie and Namoi Rivers. However, larger scale spatial differences between rivers were the largest source of variation in the data. The interaction between temporal change and spatial variation in fish community structure, whilst statistically significant, was smaller than the variation between rivers. This suggests that although the fish communities within each river changed between sampling occasions, the underlying differences between rivers were maintained. In contrast, the strongest interaction between temporal and spatial effects occurred at the smallest spatial scale, at the level of individual sites. This means whilst the composition of the fish assemblage at a given site may fluctuate, the magnitude of these changes is unlikely to affect larger scale differences between reaches within rivers or between rivers. These results suggest that sampling at any time within a single season will be sufficient to show spatial differences that occur over large spatial scales, such as comparisons between rivers or between biogeographical regions.  相似文献   
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