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711.
Offset schemes help avoid or revert habitat loss through protection of existing habitat (avoided deforestation), through the restoration of degraded areas (natural regrowth), or both. The spatial scale of an offset scheme may influence which of these 2 outcomes is favored and is an important aspect of the scheme's design. However, how spatial scale influences the trade-offs between the preservation of existing habitat and restoration of degraded areas is poorly understood. We used the largest forest offset scheme in the world, which is part of the Brazilian Forest Code, to explore how implementation at different spatial scales may affect the outcome in terms of the area of avoided deforestation and area of regrowth. We employed a numerical simulation of trade between buyers (i.e., those who need to offset past deforestation) and sellers (i.e., landowners with exceeding native vegetation) in the Brazilian Amazon to estimate potential avoided deforestation and regrowth at different spatial scales of implementation. Allowing offsets over large spatial scales led to an area of avoided deforestation 12 times greater than regrowth, whereas restricting offsets to small spatial scales led to an area of regrowth twice as large as avoided deforestation. The greatest total area (avoided deforestation and regrowth combined) was conserved when the spatial scale of the scheme was small, especially in locations that were highly deforested. To maximize conservation gains from avoided deforestation and regrowth, the design of the Brazilian forest-offset scheme should focus on restricting the spatial scale in which offsets occur. Such a strategy could help ensure conservation benefits are localized and promote the recovery of degraded areas in the most threatened forest landscapes.  相似文献   
712.
Market-based conservation mechanisms are designed to facilitate the mitigation of harm to and conservation of habitats and biodiversity. Their potential is partly hindered, however, by the quantification tools used to assess habitat quality and functionality. Of specific concern are the lack of transparency and standardization in tool development and gaps in tool availability. To address these issues, we collected information via internet and literature searchers and through conversations with tool developers and users on tools used in U.S. conservation mechanisms, such as payments for ecosystem services (PES) and ecolabel programs, conservation banking, and habitat exchanges. We summarized information about tools and explored trends among and within mechanisms based on criteria detailing geographic, ecological, and technical features of tools. We identified 69 tools that assessed at least 34 species and 39 habitat types. Where tools reported pricing, 98% were freely available. More tools were applied to states along the U.S. West Coast than elsewhere, and the level of tool transferability varied markedly among mechanisms. Tools most often incorporated conditions at numerous spatial scales, frequently addressed multiple risks to site viability, and required 1–83 data inputs. Most tools required a moderate or greater level of user skill. Average tool-complexity estimates were similar among all mechanisms except PES programs. Our results illustrate the diversity among tools in their ecological features, data needs, and geographic application, supporting concerns about a lack of standardization. However, consistency among tools in user skill requirements, incorporation of multiple spatial scales, and complexity highlight important commonalities that could serve as a starting point for establishing more standardized tool development and feature-incorporation processes. Greater standardization in tool design may expand market participation and facilitate a needed assessment of the effectiveness of market-based conservation.  相似文献   
713.
鄱阳湖生态环境保护与资源利用技术模式研究   总被引:2,自引:0,他引:2  
鄱阳湖是我国第一大淡水湖泊,也是国际重要湿地,在维系长江水量平衡和生态安全方面,发挥着十分重要的作用和功能。近年来,鄱阳湖生态环境受到经济发展和人口增长的威胁,主要表现为:湿地生态系统退化,湖泊生态功能下降,流域生物多样性减少,水生植被萎缩,水污染程度日趋严重。湖区内产业结构和资源利用的不合理也限制了其经济发展。建设鄱阳湖生态经济区发展战略的确立要求江西尽快探索出一条保护生态与发展经济的双赢之路。结合鄱阳湖区生态环境与资源利用现状,通过2 a多的集成研究与示范,已形成了湿地恢复、沙化综合治理、农业污染治理和资源合理利用等十多种技术模式,在保护环境的同时提高了农民收入,为实现鄱阳湖生态经济区建设目标提供了技术支撑.  相似文献   
714.
目前,已有很多研究致力于讨论保护规划中整合保护效益和经济成本的重要性。为丰富解决该问题的思路,从系统保护规划理念出发,应用MARXAN模型软件对长江流域两栖爬行类生物多样性保护优先区进行了选择和评价。研究中共选择两栖物种54个,爬行物种73个作为指示物种,并按濒危性和特有性划分为5个类型。综合考虑每个类型的特定保护目标,以县域人均GDP为相对保护成本,探讨如何选择达到保护目标的最低经济成本区域。通过运算每个规划单元的不可替代性,共选定保护优先区9个,包括121个县(市、民族自治县)。建议以9个保护热点区为基础,率先建立各区域内保护网络,同时在已建保护区日常巡护中加入两栖爬行动物巡护内容。  相似文献   
715.
文中所说“总量控制”,全称是污染物排放总量控制制度。当污染物超出环境容量,总量控制一般以削减现有总量的方式出现,也就是通常所说的“减排”。结构减排在减排中占据主导的核心地位。实践表明,“节能必减排,减排促节能”。节能减排相结合是推动经济发展方式转变、调整经济结构、提高自主创新能力、实现环境与发展“双赢”的一种有效途径,也是科学发展的必然要求。节能减排与应对气候变化密不可分,是应对气候变化的主要支撑面。控制温室气体(以CO2为代表)排放强度,是对污染物排放总量控制制度的深化与发展。  相似文献   
716.
The purpose of this study is to examine the origin, development, and characteristics of terraces (kella), plus their potentials and determinants for sustainable use in the Chencha–Dorze Belle area of southern Ethiopia. Field surveys were conducted to determine the various parameters of the indigenous terraces and in order to collect samples for radiocarbon dating. To identify farmers’ views of the terrace systems, semi-structured interviews and group discussions were also carried out. Terraces were built and used—as radiocarbon dating proves—at least over the last 800 years. The long-term continued usage of the indigenous terraces is the result of social commitments, the structural features of the terraces, and the farmers’ responses to the dynamics of social and cultural circumstances. We dubbed that the terraces are a success story of fruitful environmental management over generations. Thus, a strong need is to preserve and develop this important cultural heritage and example of sustainable land use.  相似文献   
717.
Michael E. McClain 《Ambio》2013,42(5):549-565
Sustainable development in Africa is dependent on increasing use of the continent’s water resources without significantly degrading ecosystem services that are also fundamental to human wellbeing. This is particularly challenging in Africa because of high spatial and temporal variability in the availability of water resources and limited amounts of total water availability across expansive semi-arid portions of the continent. The challenge is compounded by ambitious targets for increased water use and a rush of international funding to finance development activities. Balancing development with environmental sustainability requires (i) understanding the boundary conditions imposed by the continent’s climate and hydrology today and into the future, (ii) estimating the magnitude and spatial distribution of water use needed to meet development goals, and (iii) understanding the environmental water requirements of affected ecosystems, their current status and potential consequences of increased water use. This article reviews recent advancements in each of these topics and highlights innovative approaches and tools available to support sustainable development. While much remains to be learned, scientific understanding and technology should not be viewed as impediments to sustainable development on the continent.  相似文献   
718.
Vernon George Thomas 《Ambio》2013,42(6):737-745
Proposals to end the use of lead hunting ammunition because of the established risks of lead exposure to wildlife and humans are impeded by concerns about the availability, price, and effectiveness of substitutes. The product availability and retail prices of different calibers of lead-free bullets and center-fire rifle ammunition were assessed for ammunition sold in the USA and Europe. Lead-free bullets are made in 35 calibers and 51 rifle cartridge designations. Thirty-seven companies distribute internationally ammunition made with lead-free bullets. There is no major difference in the retail price of equivalent lead-free and lead-core ammunition for most popular calibers. Lead-free ammunition has set bench-mark standards for accuracy, lethality, and safety. Given the demonstrated wide product availability, comparable prices, and the effectiveness of high-quality lead-free ammunition, it is possible to phase out the use of lead hunting ammunition world-wide, based on progressive policy and enforceable legislation.  相似文献   
719.
相对湿度是文物保存环境的一个极其重要的参数,NOx耦合水分对于文物的破坏性很大。在前期开发的空气净化器的基础上,研究了空气净化和湿度调节系统集成技术和参数,考察了空气净化器各单元对NOx的去除率,并评价了流量和相对湿度的影响,结果发现不同净化单元的设置合理有效。相对湿度低的情况下,氮氧化物去除率较高,达到96%以上,但在相对湿度较高的情况下则降低为66%。将空气净化器串联了调湿装置后,发现调湿器调湿效果显著,在各种环境湿度的情况下能有效的保持展柜的湿度。但在降湿效果上有待提高,调湿器的结构以及参数需要进一步优化。  相似文献   
720.
改革开放以来,农村减灾防灾投入不断加强,水利减灾措施对农业发展做出了巨大贡献。特别是2011年中央进一步强调加强水利基础设施建设的重要作用,决定在"十二五"期间加大水利投资,新一轮的水利建设正在全国全面展开。为了更有效地发挥水利综合减灾措施的作用,合理地进行投入,科学配置各种水利减灾资源,必须了解和掌握灾害承受体如水库、堤防等的承灾能力状况,以指导我们合理安排水利减灾投入。应用灰色关联分析法对各个减灾措施的效果进行了排序分析,并据此提出了对今后投入调整的建议。  相似文献   
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