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41.
A multinational collaborative study during the summer of 1983 addressed organizational alternatives in natural systems management. Participants were particularly interested in ways different governments attempted to resolve the disparity between the interconnected quality of nature and the compartmentalized structure of bureaucracies. Five patterns of organization have evolved to meet this challenge: mission agencies managing ecosystems; independent or interagency central environmental units: environmental units within mission agencies; environmental components within central planning units; and regional superagencies. The systems developed by five nations—the United States, Korea, Malaysia, the Philippines, and Thailand—are analyzed and compared in terms of these five patterns.  相似文献   
42.
The European Union’s Green Deal and associated policies, aspiring to long-term environmental sustainability, now require economic activities to ‘do no significant harm’ to EU environmental objectives. The way the European Commission is enacting the do no significant harm principle relies on quantitative tools that try to identify harm and adjudicate its significance. A reliance on established technical approaches to assessing such questions ignores the high levels of imprecision, ambiguity, and uncertainty—levels often in flux—characterizing the social contexts in which harms emerge. Indeed, harm, and its significance, are relational, not absolute. A better approach would thus be to acknowledge the relational nature of harm and develop broad capabilities to engage and ‘stay with’ the harm. We use the case of European research and innovation activities to expose the relational nature of harm, and explore an alternative and potentially more productive approach that departs from attempts to unilaterally or uniformly claim to know or adjudicate what is or is not significantly harmful. In closing, we outline three ways research and innovation policy-makers might experiment with reconfiguring scientific and technological systems and practices to better address the significant harms borne by people, other-than-human beings, and ecosystems.  相似文献   
43.
Legitimizing Fluvial Ecosystems as Users of Water: An Overview   总被引:6,自引:0,他引:6  
We suggest that fluvial ecosystems are legitimate users of water and that there are basic ecological principles guiding the maintenance of long-term ecological vitality. This article articulates some fundamental relationships between physical and ecological processes, presents basic principles for maintaining the vitality of fluvial ecosystems, identifies several major scientific challenges and opportunities for effective implementation of the basic ecological principles, and acts as an introduction to three specific articles to follow on biodiversity, biogeochemistry, and riparian communities. All the objectives, by necessity, link climate, land, and fresh water. The basic principles proposed are: (1) the natural flow regime shapes the evolution of aquatic biota and ecological processes, (2) every river has a characteristic flow regime and an associated biotic community, and (3) aquatic ecosystems are topographically unique in occupying the lowest position in the landscape, thereby integrating catchment-scale processes. Scientific challenges for the immediate future relate to quantifying cumulative effects, linking multidisciplinary knowledge and models, and formulating effective monitoring and assessment procedures. Additionally, forecasting the ecological consequences of changing water regimes is a fundamental challenge for science, especially as environmental issues related to fresh waters escalate in the next two to three decades.  相似文献   
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随着太湖地区的经济发展及湖泊资源的利用,太湖水草的爆发性生长已经成为提高太湖水质、维持生态系统稳定的严重阻碍。水草枯亡后可能会导致水质异常,进而给苏州市饮用水安全带来威胁。依据4年来对太湖主要湖区水草的群落结构、分布范围、季节更替的研究,初步构建了太湖水草监管体系,为政府部门实施系统性监管提供支撑,并在全国湖泊水草监管方面发挥积极的示范作用。  相似文献   
46.
旅游季节性是一个旅游研究的常态问题。本文对近年来旅游季节性研究成果进行了综述,有助于深入了解旅游季节性影响因素以及动力机制,尤其指出旅游的季节性对生态环境的影响尤为严重,应格外重视旅游季节性问题,积极发展生态旅游,从而实现旅游地的可持续发展。  相似文献   
47.
膜分离技术在油气回收中的应用   总被引:1,自引:0,他引:1  
在油品储运、销售、应用过程中,存在着大量的油品蒸发损耗。可用膜分离技术来分离回收轻质油品蒸发排放出来的油气。介绍膜法油气回收的分离机理、应用实例和工艺设计数据,综合比较常用的吸收法、吸附法、冷凝法及膜法油气回收技术并获得各自的量化分值,认为膜法回收技术为目前较有可能及较容易取得突破成果的研究领域。最后指出今后的研究重点。  相似文献   
48.
小型水射流旋转喷头是一种可广泛应用于各行各业各种类型清洗的装置。它利用泵加压后水能产生的力,通过行星轮系及喷嘴偏心使喷头自转,产生旋转射流,扩大清洗面,对提高清洗效率的研究及应用有一定的参考价值。  相似文献   
49.
In the electricity sector, innovation in large-scale storage is anticipated to reduce costs and improve performance. The effect on greenhouse gas emissions of lower storage costs depends on the interactions between storage and the entire grid. The literature has disagreed on the role of storage in reducing emissions. In this paper we present a stylized model, which suggests that the effect of storage costs on emissions depends on the supply responsiveness of both fossil and renewable generators. Under common conditions in the United States, lower storage costs are more likely to reduce emissions when wind investment responds to equilibrium electricity prices and when solar investment does not. Simulations of a computational model of grid investment and operation confirm these intuitions. Moreover, because of its effect on coal and natural gas–fired supply responsiveness, introducing a carbon dioxide emissions price may increase the likelihood that lower storage costs reduce emissions.  相似文献   
50.
文章从万寿菊无土栽培技术要点出发,对万寿菊无土栽培技术进行简单的研究,力图筛选出万寿菊适于生产应用的栽培基质和营养液的配方,为研究万寿菊的无土栽培和应用提供理论依据。进而为花卉无土栽培提供科学依据,从而更好的保护土壤环境。  相似文献   
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