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Steven J. Cooke Abigail J. Lynch John J. Piccolo Julian D. Olden Andrea J. Reid Steve J. Ormerod 《水产资源保护:海洋与淡水生态系统》2021,31(6):1499-1511
- In 1949, Aldo Leopold formalized the concept of the ‘land ethic’, in what emerged as a foundational and transformational way of thinking about natural resource management, biodiversity conservation, and stewardship in terrestrial systems. Yet, the land ethic has inherent linkages to aquatic ecosystems; Leopold himself conducted research on rivers and lakes, and freshwater ecosystems figured widely in his writing.
- We reflect on the land ethic and other aspects of Leopold's scholarship to identify key messages that provide insight into the stewardship and management of freshwater ecosystems around the globe. We also frame what we call the ‘freshwater ethic’ around Leopold's legacy. Although Leopold could not have envisaged the stressors affecting modern aquatic ecosystems, his core principles remain salient. These apply not only to ecosystem protection, but also to the ethics of modern conservation economics, sustainability, and the protection of natural capital, in which lakes, rivers, and wetlands now figure prominently.
- We identify key ‘Aldo-inspired’ recommendations for protecting and restoring freshwater ecosystems in the Anthropocene that emanate directly from his writings (e.g. adopt an ecosystem approach, identify win–win–win scenarios, recognize the irreplaceability of wild waters, and strive for freshwater optimism).
- In an epoch where links between people and nature are becoming more explicit in environmental management, policy, and governance, we suggest that Aldo Leopold's work illustrates how inspirational, seminal thinkers have offered leadership in this domain. We contend that today there is still much that can be learned from Leopold, especially by the next generation of environmental practitioners, to ensure the effective stewardship of our aquatic ecosystems.
- We submit that the adoption of a freshwater ethic in parallel with Leopold's land ethic will enhance the stewardship of the world's increasingly threatened fresh waters by raising the profile of the plight of fresh waters and identifying enduring actions that, if embraced, will help conserve and restore biodiversity.
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The rhizobia-legume symbiosis is the main source of fixed nitrogen for many agricultural systems. However, it is inhibited by low soil temperature. To date, research on nodulation has involved either qualitative or destructive analyses. The use of computer-based image analysis potentially allows nodules to be followed during the course of development. Seedlings of bean (Phaseolus vulgaris L.), lentil (Lens culinaris Medik.) and pea (Pisum sativum L.) were transplanted into plastic growth pouches suspended in water baths maintained at 10, 15, 20 or 25 °C. Two days after transplanting, all plants were inoculated with appropriate rhizobial strains. Seven days after inoculation, plant roots were scanned; this was repeated weekly for 7 weeks. Data on nodule length were collected through image analysis. Nodule length was correlated with nodule size and development. There were increases in the precision of estimates of environmental effects through observation of individual nodule development, as opposed to averages for populations of nodules. The effects of root temperature on nodulation and nodule development were observed both in the delayed onset of nodulation and in reduced subsequent nodule growth rate, resulting in effects on final nodule size. 相似文献
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This paper attempts to contribute to the forestry valuation literature by providing a template for executing ex ante cost–benefit analyses of large-scale temperate plantation forestry programmes, taking the Irish Government's Forestry Plan as an example. An ex ante assessment of the social efficiency of the Plan is undertaken and, in doing so, a range of externalities is examined using, inter alia, contingent valuation and production function approaches. The appropriate magnitude of subvention of the Plan is also examined. The study demonstrates how large-scale forestry programmes and their external effects, both positive and negative, can be evaluated. In so doing, it provides insights into the methodological difficulties and solutions for assessing the social efficiency of large-scale environmental projects and the appropriate level of their subsidisation. 相似文献
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通过对渝北区宝圣湖整治措施、整治效果及存在的问题进行分析,结合城市湖库污染成因,探讨了宝圣湖水环境保护长效管理机制及城市湖库环境保护措施,为城市湖库及其他地表水的保护提供依据。 相似文献
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J.S. Weese S. Giguère L. Guardabassi P.S. Morley M. Papich D.R. Ricciuto J.E. Sykes 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):487-498
The epidemic of antimicrobial resistant infections continues to challenge, compromising animal care, complicating food animal production and posing zoonotic disease risks. While the overall role of therapeutic antimicrobial use in animals in the development AMR in animal and human pathogens is poorly defined, veterinarians must consider the impacts of antimicrobial use in animal and take steps to optimize antimicrobial use, so as to maximize the health benefits to animals while minimizing the likelihood of antimicrobial resistance and other adverse effects. This consensus statement aims to provide guidance on the therapeutic use of antimicrobials in animals, balancing the need for effective therapy with minimizing development of antimicrobial resistance in bacteria from animals and humans. 相似文献
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我国农村环境趋恶原因与制度策略 总被引：2，自引：0，他引：2
分析了农村环境日趋恶化的原因,从健全环境补偿机制、构建城乡一体化的环境影响评价制度、保障农民的环境参与权和利益请求权3方面,探讨了完善我国农村环境保护的制度策略。 相似文献
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