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151.
Because seas and coastlines are shared between states, the formulation and implementation of marine spatial planning (MSP) should be transboundary by nature. The main argument of this paper is that MSP should be organized as a transboundary policy-making process, but this is hampered by the conceptual and institutional fragmentation MSP is facing. Based on an analysis of four transboundary planning processes in different European seas, the paper gives insight into the possibilities to develop and implement transboundary marine spatial planning (TMSP). To overcome the conceptual and institutional challenges, TMSP should be developed as a reflexive governance arrangement, in which the actors involved are able to change the rules of the game and to challenge the existing (national-oriented) MSP discourses. The paper develops four forms of reflexivity (unreflectiveness; performative reflectiveness; structural reflectiveness; and reflexivity) to assess TMSP processes and to formulate conditions which are crucial to develop TMSP as a reflexive marine governance arrangement.  相似文献   
152.
Harbour porpoises (Phocoena phocoena) and harbour seals (Phoca vitulina) were found to differ in the ability to metabolize polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Biomagnification factors (BMFs), calculated between both predators and their prey (sole - Solea solea and whiting - Merlangius merlangus), had a large range of variation (between 0.5 and 91 for PCBs and between 0.6 and 53 for PBDEs). For the higher chlorinated PCBs and the highest brominated PBDEs, the BMF values in adult males were significantly higher than in the juvenile individuals of both species. BMF values of hexa- to octa-PCBs were the highest, suggesting reduced ability to degrade these congeners. Harbour porpoises had higher BMFs for lower chlorinated PCBs and for all PBDEs compared to harbour seals. Other factors, which may influence biomagnification, such as the octanol-water partition coefficients and the trophic level position measured through stable isotope (δ15N) analysis, were found to be of lesser importance to predict biomagnification in the studied food chain.  相似文献   
153.
We determined egg concentrations of organochlorines and thickness of eggshells from brown boobies at eight colonies ranging from the northern Gulf of California to southern Mexico. The only common residue was that of DDE, which was found in almost all eggs. DDE content apparently reflected pre-1990 DDT use in nearby agricultural areas and, at one site, intensive mosquito control for high-end tourism development. There were no inter-colony differences in eggshell thickness, and variation in this variable likely reflected individual bird characteristics and/or individual feeding source. This variable was not a good proxy to DDE exposure of brown boobies, under current DDE levels in the brown booby trophic chain. In the northern Gulf of California, eggshell thickness has recovered to pre-DDT conditions. Our data indicate that the Gulf of California and southwestern coast of Mexico have a healthy near-shore marine environment, as far as organochlorines are concerned.  相似文献   
154.
The biosorption of the heavy metals Cu2+ and Zn2+ by dried marine green macroalga (Chaetomorpha linum) was investigated. The biosorption capacities of the dried alga for copper and zinc were studied at different solution pH values (2–6), different algal particle sizes (100–800 μm) and different initial metal solution concentrations (0.5–10 mM). An optimum pH value of 5 was found suitable for both metal ions biosorption for both metal ions. At the optimum particle size (100–315 μm), biosorbent dosage (20 g/l) and initial solution pH (pH 5), the dried alga produced maximum copper and zinc uptakes values (qmax) of 1.46 and 1.97 mmol/g respectively (according to the Langmuir model). The kinetic data obtained at different initial metal concentrations indicated that the biosorption rate was fast and most of the process was completed within 120 min. This study illustrated an alternative technique for the management of unwanted biological materials using processed algal material. C. linum is one of the fast-growing marine algae in the lake of Tunis and could be utilized as a biosorbent for the treatment of Cu2+ and Zn2+ contaminated wastewater streams.  相似文献   
155.
A group of 26 European ports was interviewed to understand their requirements for environmental information and to establish how widespread the use of Earth Observation (EO) data was amongst them. Aspects covered by the research included port profile characterisation, environmental management activities, environmental needs and current monitoring practices. The study reflected the diversity amongst European ports and their environmental performances. Most of the ports were publicly owned and located in estuaries and rivers. General cargo was the most popular commodity handled. Practically all the ports had an environmental policy in place and half of them had been accredited by an external body. The main environmental parameters that ports required to be monitored were marine related issues (currents, waves and tide), water quality, meteorological parameters, turbidity and sediment processes. The principal driver for monitoring was maintaining key port operations, followed by legislation, and local responsibilities. Ports in general collected their own data in situ and only one-third had used remotely sensed data (data from Earth Observation satellites or from airplane mounted sensors) for environmental purposes. Half of them used computer modelling. This study was conducted within the framework of the European funded port environmental information collector project (PEARL).  相似文献   
156.
Rapid growth in marine sand mining for construction and other uses poses environmental challenges to coastal nations virtually worldwide. Yet the development of management policies, such as a system of fees imposed on operators for damage caused by mining, has been frustrated by a lack of studies to support such measures. Adapting a Beverton-Holt bioeconomic model, this paper attempts to contribute to the estimation of external costs to commercial fisheries due to marine mining. Using the major mining area of Ongjin in Korea as a case study, we estimate economic losses in use value of commercial fisheries through the time to recovery of the injured resource stocks. Present value of lost catch over a 1-year period from mining to resource recovery is estimated at $38,851 for a single “prototype” mining site. Estimated cumulative damages due to recurring mining for 5 and 10 years are $1.5 million and $2.2 million, respectively, at 20 mining sites. Sensitivity analyses are used to examine the effects of alternative assumptions to assess the many sources of uncertainty. Using a form of meta-analysis, dose-response information is used to assess the excess mortality the mining sediment plume has on eggs and larvae and, ultimately, on the value of lost catch ($841). Also addressed is the importance of specifying the appropriate “premining” conditions against which to assess environmental losses at the mining site. Damages estimated with premining fish populations are $23,066 higher than is the case using postmining conditions. Overall, the illustrative results suggest the variety of complex conditions which influence damage to fisheries from mining and which can benefit from further study to improve management guidelines. An erratum to this article can be found at  相似文献   
157.
During the past 25 years, the management of marine ecosystems has evolved significantly. Due to the increased use of the sea and the increased awareness of adverse impacts of certain human activities in and around the sea, which has been a common good for a long time—‘Mare Liberum’—an international and integrated approach has become increasingly important to regulate the use of our common seas. From the late 1960s onwards, intergovernmental meetings have taken place in order to tackle the problems of international pollution of seas and oceans. One reason for this attention was the Torrey Canyon accident in 1967, which triggered the start of the Bonn Agreement in 1969 for coordinating the combat mission against oil and chemical spills in the North Sea. After the 1972 United Nations Conference on the Human Environment in Stockholm, with the involvement of the European Union, the International Council for Exploration of the Sea (ICES) and Non-Governmental Organizations (NGOs), other regional and global Conventions, as well as the North Sea Ministerial Conferences were established. These continuous international efforts have resulted in a considerable reduction of the input of certain contaminants and of nutrients (in particular phosphate) into the marine environment. However, not all problems have yet been solve. The North Sea Ministers agreed at the Conference in Esbjerg (1995) to aim at a reduction of the input of all hazardous substances within one generation, in order to reach the goal of negligible risks of pollution. Furthermore, there is a general aim to minimize adverse effects of disturbing activities. The challenge, now and in the future, is to find a balance between economic development and environmental protection of our international marine waters aiming at a sustainable development of the marine resources by employing scientifically based measures and, in situations where there are reasonable grounds for concern but no conclusive links between cause and problem, applying the precautionary principle with respect to pollution and disturbing activities.  相似文献   
158.
选择出11项评价因子,采用单项分指数法和平均分指数法,在涨潮、落潮、涨落潮时分别对伶仃洋东部海域水质进行监测,并与历史资料进行对比,对评价因子超标进行评价和原因分析,提出了补救与预防措施.  相似文献   
159.
海洋大气腐蚀性分类分级   总被引:6,自引:0,他引:6  
本文介绍了国内外大气腐蚀性分类分级的主要方法和发展状况,论述了在我国沿海开展大气腐蚀性研究的重要性,并提出了开展该项研究着重需要考虑的几个问题。  相似文献   
160.
• Reclamation projects are important disturbances on microplastic risk in coasts. • Tidal-flat reclamation area is a large storage medium for sedimentary microplastics. • Aging and distribution features of soil microplastics show spatial heterogeneity. • Coastal weathered engineering geotextiles are a significant threat to marine health. Coastal tidal flats have received considerable attention in recent years, as they provide a direct channel for the discharge of terrestrial microplastics into the ocean. Land reclamation is occurring increasingly frequently in coastal tidal-flats; however, the environmental impacts of these activities remain unclear. Therefore, this pioneering study assessed the microplastic emission characteristics of reclamation geotextiles and performed a risk assessment accordingly. Morphological characterization of geotextile samples collected from five sites in Dongtai, China, provided evidence of sedimentary weathering. Based on several assumptions, the average abundance of microplastics in soil covered by geotextiles was estimated to reach 349±137 particles/kg dry weight, with the total microplastic load in the reclaimed area estimated to be 20.67±8.06 t. Compared with previous studies, this research demonstrates that coastal reclamation areas store a high concentration of microplastics, aggravating marine microplastic pollution. Moreover, conditional fragmentation model results revealed that the weathering and distribution characteristics of soil microplastics in coastal tidal-flat areas exhibit spatial heterogeneity, being more easily affected by natural factors (such as tides) than those in inland areas. As a result of tides, the annual discharge of geotextile-originating microplastics from the studied areas into the ocean was approximately 2465.52±960.77 t. These findings prove that the risks posed by engineering-microplastics are significant, indicating that further investigations are required on the precise laws of transfer and migration, as well as the toxicity mechanisms, in order to improve analytical techniques and policies in this field.  相似文献   
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