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This paper investigates the potential flexibility within the current legal frameworks governing marine aquaculture across Europe to cater for the installation and management of marine biofilters alongside fish farms. The basis for debate is that deployment of these biofilters could be used to facilitate environmental impact mitigation. Furthermore, they have the potential to facilitate the development of bi-culture or polyculture through the harvesting of species from the biofilters themselves, for example, mussels (Mytilus edulis). This study explores the flexibility within and suitability of the current legal systems within Europe to cater for the specific technology’s adoption and management. The challenges identified from the legislative and policy frameworks are discussed along with the applicability of these to the use of biofilters for the development of bi-culture. Penultimately, recommendations are made as to where additional measures are needed and the challenges and difficulties that such measures will need to overcome before biofilters can be applied for environmental impact mitigation. Finally, the paper illustrates an application of ‘Comparative Legal Analysis’, demonstrating links to the question in hand and through so doing to wider coastal issues.  相似文献   
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1. A key component of physical habitat along braided river systems is the exposed riverine sediment within the active zone. The relatively unmanaged, gravel‐bed Fiume Tagliamento, Italy, provides the focus for exploring two ecologically important properties of exposed riverine sediments: their within‐patch and between‐patch variability in calibre. 2. To characterize between‐patch variation in exposed riverine sediments, replicate (within‐patch) samples were obtained from three geomorphologically distinct locations along 130 km of the river: bar heads along the margin of the low‐flow channel, the heads of major bars across the exposed surface of the active zone, and floodplain surfaces. A photographic technique enabled rapid and consistent field sampling of the coarse sediments at bar heads along the low‐flow channel margin and on major bars across the dry bed. 3. A downstream decrease in particle size and an increase in within‐patch heterogeneity in sediment size were observed within bar head sediments along the margin of the low‐flow channel. Comparisons between major bar and low‐flow channel samples revealed greatest within‐patch variability in individual sediment size indices (D50, A‐ and B‐axes of the larger particles) at headwater sites, greatest between‐patch variability in the three measured indices in the central reaches, and lowest between‐patch variability at downstream sites. However, there was a distinct increase in the overall heterogeneity in particle size, which was sustained across all patches, in a downstream direction. 4. There was a clear downstream decrease in the size of floodplain sediments in the headwaters, but thereafter there was no distinct downstream trend in any of the calculated particle size indices. 5. The geomorphological controls on the observed patterns and the potential ecological significance of the patterns, particularly for plant establishment, are discussed in relation to the relative relief of the active zone, and the highly variable hydrological and climatic regime along the river. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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