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1.
Our GIS based project aims at producing a classification scheme to develop a typology of the bottom of the Bay of Gdansk in the southern Baltic. The typology was based on the abiotic factors which are used to define water body types by the European Water Framework Directive (WFD). Significance analysis of particular factors has shown that within the discussed area wave exposure seems to play the most important role. All other factors are to a greater or lesser degree correlated with these two. Taking into consideration the shallows and the varied coastline of the investigated area it was decided to make use of the SWAN numerical wave model to determine the influence of wave impact upon the bottom. The model was used to produce raster maps of orbital velocity near the bottom for each wind scenario. With the help of the GIS analysis the maps were turned into layers: the mean velocity and the maximum velocity at the bottom. To produce the layer of yearly amount of solar radiation a GIS model was built which main parameters were the layer of depth and three layers of turbidity for three seasons. The layers of the maximum orbital velocity and of the solar radiation at the bottom were then used in a classificatory procedure consisted in an iterative sequence of the three following steps: cluster formation, dendrogram analysis and classification using the maximum likelihood method. Ecological importance of the classification has been obtained by means of the aggregation of a part of classes based upon the statistics calculated for them within the GIS system with the help of the zonal function out of the following parameters: salinity, depth, mean and maximum orbital velocity at the bottom, temperature differences between warm and cold seasons, solar radiation, and type of sediments. The method proposed here makes it possible to produce high resolution thematic maps of the bottom even with incomplete data cover of the investigated area.  相似文献   
2.
Validation of the AZTI's Fish Index (AFI), proposed for the Basque Country (northern Spain), in assessing fish quality within the Water Framework Directive (WFD), is undertaken. The response to anthropogenic pressure is investigated, in setting the boundaries between the different quality status classes. Hence, 12 estuaries were sampled, at different frequencies, between 1989 and 2007, by means of a beam trawl. Significant (p < 0.0001) correlations were found between the AFI and oxygen saturation and ammonia. Oxygen quality standards are used to set boundaries between quality classes. Then, the AFIs obtained are compared with different anthropogenic pressures, including urban and industrial discharges, engineering works and dredging. The effects of the removal of some of these pressures are also studied. The total number of pressures within an estuary shows significant (p < 0.009) negative correlation with AFI, explaining between 51 and 62% of the variability in fish quality. The impact of pressures upon fish and demersal assemblages is detected as required by the WFD. Nonetheless, further investigation and intercalibration of the methods used, are necessary.  相似文献   
3.
The EU Water Framework Directive (WFD) requires the ecological assessment of water bodies. Since the littoral zones and the lakeshores are part of lakes as water bodies as defined by the WFD, a new scheme for ecological quality assessment of lakeshores should be established. It is proposed that this scheme should go beyond the formal requirements of the WFD, as it includes aspects of nature conservancy, landscape protection, and regional planning and development. Some of these aspects are subject to other EU legislation (e.g. Habitats Directive) and some are subject to national legislation. Ten general Quality Elements (QEs) are proposed, which can be refined and reified through several levels of detail, depending on the specific aims of a study. A list of eleven topics, which should be discussed in the establishment of the lakeshore quality assessment scheme, is given. The more complex ones are the implementation of other EU legislation, the definition of lakeshore types and reference conditions, the stipulation of best aggregation procedures, and a better understanding of the significance of hydrological and morphological impacts on the biota.  相似文献   
4.
In 1999 the Italian Parliament approved a law encompassing all the themes of the water cycle, including monitoring of groundwater. The new regulation takes into account the EU Directives, and charges the Regions to create monitoring networks, according to Art. 8 of the Water Framework Directive (WFD). The approach of the Italian regulation is, on the whole, coherent with the technical guidelines listed in annexes II and V of the WFD. On basis of the new law, the national environment agency (APAT) gathers data and produces assessment reports on the contamination of groundwater in Italy.  相似文献   
5.
This study provided evidence that Zostera noltii presence affects macrofauna community structure independently from median sediment grain-size and that the notion of ecosystem health is rather subjective: in the present case, we recorded “good health” in terms of seagrass development, “no impact” in terms of macrobenthic biotic indices and “negative effect” for a given key-population. The occurrence and development of a Z. noltii seagrass bed was surveyed at Banc d’Arguin, Arcachon Bay (France), to estimate the modification of the macrozoobenthic community and of the dynamics of a key-population for the local ecosystem, – the cockle Cerastoderma edule. Even though median grain-size of the sediment decreased only at the very end of the survey, i.e. when seagrass totally invaded the area, most of the macrofauna community characteristics (such as abundance and biomass) increased as soon as Z. noltii patches appeared. The structure of the macrofauna community also immediately diverged between sand and seagrass habitats, without however modifying the tested biotic indices (BENTIX, BOPA, AMBI). The health of the cockle population (growth, abundance, recruitment) was impacted by seagrass development. Related parasite communities slowly diverged between habitats, with more parasites in the cockles from seagrass areas. However, the number of parasites per cockle was always insufficient to alter cockle fitness.  相似文献   
6.
The status of water quality of Irish estuaries is reviewed; this sheds light on the rationale behind the design of the national monitoring programme. Relative to other EU Member States, Ireland's coastal monitoring programme is relatively young and not as advanced. The monitoring programmes in Ireland pre Water Framework Directive (WFD) were structured on a salinity-based typology, with an emphasis on quantifying the variability of the component elements. Although monitoring is a significant obligation under the WFD, there is little guidance on developing monitoring protocols; Member States are developing ad hoc monitoring programme. The Irish Environmental Protection Agency (EPA), responsible authority, undertook research programmes to assist design and implementation of the WFD. A substantial new national monitoring programme was developed. However, the Irish programme is not optimised; the programme is being refined to include elements not yet covered, notably the biota. New research, by the authors, aims to develop a robust approach towards monitoring integrating data and model results. This paper presents changes in Irish marine water quality monitoring policy and some of the associated research necessary to change policy.  相似文献   
7.
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
8.
An essential prerequisite for the assessment of the ecological quality of marine ecosystems is the understanding of the natural variability and its effect on the performance of quality indices. This study is focused on the long-term natural variability of diversity, biotic and multimetric indices by using long-term macrofauna data of a coastal area in the southern North Sea (1978-2005). The univariate and most biotic and multimetric indices respond significantly on specific natural disturbance events such as cold winters, but the strength of response varied between indices as well as between events. As a result, the ecological quality status can decrease over a range of 3 (out of 5) classification units. The overall ecological quality was good to high, but an increase of indices occurred from the mid 1980s onwards due to changes in the climate regime. This long-term variability has to be considered within ecological quality assessment schemes.  相似文献   
9.
The political dimension of water becomes highly important not only because of its scarcity, but also as a result of its sharing across national boundaries. Approximately 40% of the global population lives in transboundary water basins, 55% of which are located in Europe, emphasizing the need for cooperation and harmonization of policies. In order to better handle major water problems Europe have adopted the new EU Water Framework Directive 2000/60 the implementation of which is further discussed. Especially in Greece, management of transboundary rivers is of major importance, since roughly 25% of the country’s renewable resources are “imported”. However, lack of integrated approaches and legal agreements as well as administrative shortcomings, make transboundary cooperation and management a hard task. This study refers to 4 shared basins in Northern Greece and demonstrates the problems that occur for their sustainable management.  相似文献   
10.
A comprehensive study aimed at evaluating the occurrence, significance of concentrations and spatial distribution of priority pollutants (PPs) along the Comunidad Valenciana coastal waters (Spain) was carried out in order to fulfil the European Water Framework Directive (WFD). Additionally, PP concentrations were also analysed in the effluent of 28 WWTPs distributed along the studied area. In coastal waters 36 organic pollutants of the 71 analysed, including 26 PPs were detected although many of them with low frequency of occurrence. Only 13 compounds, which belong to four different classes (VOCs, organochlorinated pesticides, phthalates and tributyltin compounds (TBT)) showed a frequency of occurrence above 20% in coastal waters. In the results obtained until now, octylphenol, pentachlorobenzene, DEHP and TBT exceeded the annual average concentration (EQS-AAC), and only TBT surpassed the maximum allowable concentration (EQS-MAC). The most frequent contaminants determined in coastal waters were also present in WWTP effluents.  相似文献   
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