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591.
An agenda for assessing and improving conservation impacts of sustainability standards in tropical agriculture 下载免费PDF全文
Jeffrey C. Milder Margaret Arbuthnot Allen Blackman Sharon E. Brooks Daniele Giovannucci Lee Gross Elizabeth T. Kennedy Kristin Komives Eric F. Lambin Audrey Lee Daniel Meyer Peter Newton Ben Phalan Götz Schroth Bambi Semroc Henk Van Rikxoort Michal Zrust 《Conservation biology》2015,29(2):309-320
Sustainability standards and certification serve to differentiate and provide market recognition to goods produced in accordance with social and environmental good practices, typically including practices to protect biodiversity. Such standards have seen rapid growth, including in tropical agricultural commodities such as cocoa, coffee, palm oil, soybeans, and tea. Given the role of sustainability standards in influencing land use in hotspots of biodiversity, deforestation, and agricultural intensification, much could be gained from efforts to evaluate and increase the conservation payoff of these schemes. To this end, we devised a systematic approach for monitoring and evaluating the conservation impacts of agricultural sustainability standards and for using the resulting evidence to improve the effectiveness of such standards over time. The approach is oriented around a set of hypotheses and corresponding research questions about how sustainability standards are predicted to deliver conservation benefits. These questions are addressed through data from multiple sources, including basic common information from certification audits; field monitoring of environmental outcomes at a sample of certified sites; and rigorous impact assessment research based on experimental or quasi‐experimental methods. Integration of these sources can generate time‐series data that are comparable across sites and regions and provide detailed portraits of the effects of sustainability standards. To implement this approach, we propose new collaborations between the conservation research community and the sustainability standards community to develop common indicators and monitoring protocols, foster data sharing and synthesis, and link research and practice more effectively. As the role of sustainability standards in tropical land‐use governance continues to evolve, robust evidence on the factors contributing to effectiveness can help to ensure that such standards are designed and implemented to maximize benefits for biodiversity conservation. 相似文献
592.
Arctic marine mammal population status,sea ice habitat loss,and conservation recommendations for the 21st century 下载免费PDF全文
Kristin L. Laidre Harry Stern Kit M. Kovacs Lloyd Lowry Sue E. Moore Eric V. Regehr Steven H. Ferguson Øystein Wiig Peter Boveng Robyn P. Angliss Erik W. Born Dennis Litovka Lori Quakenbush Christian Lydersen Dag Vongraven Fernando Ugarte 《Conservation biology》2015,29(3):724-737
Arctic marine mammals (AMMs) are icons of climate change, largely because of their close association with sea ice. However, neither a circumpolar assessment of AMM status nor a standardized metric of sea ice habitat change is available. We summarized available data on abundance and trend for each AMM species and recognized subpopulation. We also examined species diversity, the extent of human use, and temporal trends in sea ice habitat for 12 regions of the Arctic by calculating the dates of spring sea ice retreat and fall sea ice advance from satellite data (1979–2013). Estimates of AMM abundance varied greatly in quality, and few studies were long enough for trend analysis. Of the AMM subpopulations, 78% (61 of 78) are legally harvested for subsistence purposes. Changes in sea ice phenology have been profound. In all regions except the Bering Sea, the duration of the summer (i.e., reduced ice) period increased by 5–10 weeks and by >20 weeks in the Barents Sea between 1979 and 2013. In light of generally poor data, the importance of human use, and forecasted environmental changes in the 21st century, we recommend the following for effective AMM conservation: maintain and improve comanagement by local, federal, and international partners; recognize spatial and temporal variability in AMM subpopulation response to climate change; implement monitoring programs with clear goals; mitigate cumulative impacts of increased human activity; and recognize the limits of current protected species legislation. 相似文献
593.
Santiago V. Luis Eric Jover 《Environmental science and pollution research international》2014,21(20):11933-11937
The 14th European Association of Chemical and Molecular Sciences (EuCheMS) International Conference on Chemistry and the Environment (ICCE 2013) took place on 25–28 June 2013 at the IEC and the WTC in Barcelona, Spain. The ICCE is a well-established biannual conference organized by the Division of Chemistry and the EuCheMS. 相似文献
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595.
Mapping the Conservation Landscape 总被引:12,自引:0,他引:12
596.
The ultrasonographer may be the first physician to suggest the presence of a fetal abnormality. A case of prenatally-detected meconium peritonitis is presented, with sonographic and radio-graphic correlation. 相似文献
597.
越来越多的研究将中国的环境问题归因于执法不严.但是,很少有人探索环保机构能力和环境管制以及执法之间的关系.在前人对国家能力研究的基础上,发展了一套指标体系对中国地方环保局的机构能力进行评价,并分析了环保机构能力和污染物减排之间的关系.研究表明:具有较好人力资本(而不是预算更多)的地方环保局能够更好地从事环境监管工作,地方环保局的机构能力提升对污染物减排产生显著正面效果;另外,严格的环境监管却不一定会改善环境状况.那些工业治理环境能力强的地区通常工业较发达,污染物排放量大,抵消了环保局监管执法所产生的正面收益.由此可见,要缩小环境法律法规规定的目标和环境现状之间的差距,仅靠监管手段创新和增强地方环保局的机构能力是不够的,中国还需要努力开展全社会监管环境的制度建设. 相似文献
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599.
本文从阐述生态经济系统、生态经济平衡和生态经济效益等生态经济学的基本范畴入手,揭示生态经济问题产生和演变的内在机理-生态经济系统的基本矛盾;从经济发展、人口增长、生产力进步而与资源缺口、环境容量、生态平衡等的相互关系,分析生态经济基本矛盾的种种表现;从原始社会、农业社会和工业社会等几个主要阶段,阐明生态经济基本矛盾产生和发展的一般过程,并从自然生态系统与社会经济系统在运动周期性、有序性、运行路线与运行机制等方面异同,着重论述产生生态经济基本矛盾的原因,进一步阐明生态问题演变的规律性。探讨解决生态经济基本矛盾的途径,即通过控制人口,转变经济增长方式,实施资源替代战略和地域优势互补,建立生态化的产业和区域发展模式,进行环境与资源市场化的制度创新,实现人口、资源、环境与经济的协调发展。 相似文献
600.
Mediastinal teratomas have rarely been discovered during the prenatal period. When seen during the neonatal period, these tumours have caused respiratory distress or hydrops fetalis. We present the sonographic and pathological findings of a rapidly developing anterior mediastinal teratoma causing hydrops fetalis and in utero demise at 27 weeks' gestation. 相似文献