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831.
The flow-through spectrofluorometers, FLUO-IMAGER, were developed to measure the abundance of phytoplankton, including the analysis of pigment composition and concentration of organic pollution and dissolved organic matter (DOM), in continuous mode. The measurements can be carried out without the time-consuming pretreatment of water samples. The analytical concept uses the technique of spectral fluorescent signatures (SFS), based on the systematized spectral library comprising the SFS of major phytoplankton species and chemical pollution. The SFS technique has been applied for several years in qualitative and quantitative screening of organic compounds and phytoplankton in the Baltic, North and Norwegian Seas. The results of the analysis of phytoplankton pigments, the dynamic processes of bloom development, DOM and oil pollution are presented.  相似文献   
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833.
It has been proposed that voluntary urban climate programmes overcome shortfalls in mandatory, top-down, state-led government interventions to address climate change risks. Such programmes seek commitments from households and firms to improve their environmental sustainability, but do not have the force of law. City governments are actively developing and implementing such programmes, seeking improved and accelerated urban climate action. There is little evidence, however, of whether their involvement positively affects voluntary programme performance. This article presents qualitative comparative analysis (QCA) of 26 voluntary programmes from Australia, the Netherlands and the US, seeking to understand whether, and if so how, city governments affect the performance of voluntary urban climate programmes. The results will help to inform city governments about the roles they may play in urban climate governance.  相似文献   
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835.
Dry and wet deposition onto thirty forest stands in relation to stand structure is studied by sampling throughfall and bulk precipitation. Nine measurement sites are situated in Pseudotsuga menziesii stands, ten in Pinus sylvestris and eleven in Quercus robur stands. All stands are situated within a radius of 1.2 km to assure a more or less equal air pollution load. In each stand, detailed forest structure inventories are made to determine aerodynamic roughness, collecting efficiency and surface area parameters. Measurements to data cover a four month period (April-July 1990). First results show relatively high throughfall deposition in Pseudotsuga menziesii stands. Lowest throughfall fluxes are recorded for Quercus robur and intermediate values for Pinus sylvestris stands. There are indications of a relatively strong canopy exchange in Quercus robur stands during the measurement period. Many results from forest stand structure inventories are not available yet. However, a strong relation is observed between throughfall deposition in Pseudotsuga menziesii stands and total crown volume.  相似文献   
836.
Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates. Dutch rabbits are unlikely to be a zoonotic source.  相似文献   
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839.
In order to successfully inform environmental management, environmental research needs to balance legitimacy, credibility, and salience. This paper aims to identify trade-offs and synergies between these three attributes in collaborative research for environmental management, and draws lessons for organizing such research. Empirically, it draws on a study of a research program on the ecological effects of coastal protection through sand nourishment. Our findings suggest that the legitimacy and salience of knowledge creation, particularly in an interactive governance context, are complementary. At the same time, we found trade-offs between practical relevance and fundamental knowledge creation, as well as between issue diversity and the depth and quality of scientific inquiry. Balancing the legitimacy, credibility, and salience of knowledge may be enabled by interactive knowledge creation involving policy-makers, experts and stakeholders. We conclude that successful management-oriented environmental research, particularly in the case of wicked problems, requires both a careful design of arrangements for stakeholder engagement, and well- established linkages to broader regulatory and institutional contexts.  相似文献   
840.
We examine issues to consider when reframing conservation science and practice in the context of global change. New framings of the links between ecosystems and society are emerging that are changing peoples’ values and expectations of nature, resulting in plural perspectives on conservation. Reframing conservation for global change can thus be regarded as a stage in the evolving relationship between people and nature rather than some recent trend. New models of how conservation links with transformative adaptation include how decision contexts for conservation can be reframed and integrated with an adaptation pathways approach to create new options for global‐change‐ready conservation. New relationships for conservation science and governance include coproduction of knowledge that supports social learning. New processes for implementing adaptation for conservation outcomes include deliberate practices used to develop new strategies, shift world views, work with conflict, address power and intergenerational equity in decisions, and build consciousness and creativity that empower agents to act. We argue that reframing conservation for global change requires scientists and practitioners to implement approaches unconstrained by discipline and sectoral boundaries, geopolitical polarities, or technical problematization. We consider a stronger focus on inclusive creation of knowledge and the interaction of this knowledge with societal values and rules is likely to result in conservation science and practice that meets the challenges of a postnormal world.  相似文献   
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