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431.
A comprehensive list of planning criteria for optimizing compliance in Marine Protected Areas (MPAs) was compiled and used to compare the views of recreational fishers and compliance officers for facilitating voluntary compliance in the Port Stephens - Great Lakes Marine Park (PSGLMP). Expert working groups were tasked separately with: 1) criteria identification and weighting; 2) scoring of no-take zones; 3) prioritizing and determining uncertainty; and 4) analysis of results and sensitivity testing. Multi-Criteria Analysis (MCA) revealed that both groups had similar perspectives and recommendations, despite weighting the individual planning criteria differently. Significantly, "manageability" scores for no-take zones from MCA appeared to correlate well with past numbers of enforcement actions recorded for each zone. This provides empirical evidence that adopting manageability criteria during the planning of MPAs could lead to a marked increase in voluntary compliance. As a result, greater consideration to compliance planning during MPA design and zoning is recommended in order to optimize voluntary compliance. Whilst the majority of no-take zones in the PSGLMP case study were evaluated as being relatively effective in terms of optimizing voluntary compliance, there remains considerable potential to improve design, management and use of the poorer performing zones. Finally, the study highlighted the value of recreational fisher engagement in MPA planning processes to maximize voluntary compliance and manageability.  相似文献   
432.
研究三丁基氯化锡(TBT)对中国近海常见5种硅藻和甲藻(硅藻中丹麦细柱藻(Leptocylindrus danicus)、派格棍形藻(Bacilaria paxillifera)、聚生角毛藻(Chaetoceros socialis),甲藻中微型原甲藻(Prorocentrum minimum)、简裸甲藻(Gymnodinium simplex))的毒性效应,考察了有机锡对浮游藻光合活性(Fv/Fm)、粒径、生长的影响。结果表明:派格棍形藻、聚生角毛藻、简裸甲藻的光合活性(Fv/Fm)受TBT影响较显著;微型原甲藻、丹麦细柱藻的光合活性受TBT影响较小。高质量浓度TBT胁迫下海洋微藻峰值粒径显著减小,低质量浓度TBT对峰值粒径影响不显著。低质量浓度TBT对派格棍形藻、聚生角毛藻、简裸甲藻、微型原甲藻均有较强的毒性作用,非检测毒性浓度(NDEC)分别为1.17、1.07、0.23、3.73μg.L-1,丹麦细柱藻对TBT具有很强耐受性,NDEC为112.62μg.L-1。  相似文献   
433.
In order to better understand the effects of biostimulation and bioaugmentation processes on a marine microbial community, three different mesocosm experiments were planned. Natural seawater(10.000 L) was artificially polluted with crude oil(1 L) and(1) inorganic nutrients(Biostimulating Mesocosm, BM),(2) inorganic nutrients and an inoculum of Alcanivorax borkumensis SK2(Single Bioaugmentation Mesocosm, SBM),(3) inorganic nutrients and inoculums of A. borkumensis SK2 and Thalassolituus oleivorans MIL-1(Consortium Bioaugmentation Mesocosm, CBM). During the experimental period(20 days), samples were taken from each mesocosm and the community structure was analyzed by PCR–DGGE. The 16 S r RNA gene DGGE banding patterns and sequence analysis demonstrated that biostimulation had the lowest effect on microbial biodiversity in the mesocosms; however, the biodiversity of the marine microbial community dramatically decreased in the CBM(Shannon index was 0.6 in T3). The community structures among the three mesocosms were also markedly different,and major bacteria derived from DGGE bands were related to uncultured Gamma Proteobacteria. The biodegradation results show that the Single Bioaugmentation Mesocosm(SBM) system had the highest percentage of degradation(95%) in comparison to the BM mesocosm(80%) and CBM(70%).  相似文献   
434.
This paper presents a hypothesis that could explain why blue light appears to dominate non-image-forming (NIF) ocular photoreception in marine as well as terrestrial vertebrates. Indeed, there is more and more evidence suggesting that 'novel' retinal photoreceptors, which are sensitive to blue light and were only discovered in the 1990s, could be a feature shared by all vertebrates. In our view, blue light photoreception evolved and persisted as NIF photoreception because it has been useful in the colonisation of extensive photo-dependent oceanic habitats and facilitated the move of vertebrates from an aquatic to a terrestrial environment. Because the available scattered evidence is compatible with the validity of our hypothesis, we hope that our rationale will be followed up. Indeed, it (1) involves testable predictions, (2) provides plausible explanations for previous observations, (3) unites phenomena not previously considered related to one another and (4) suggests tests that have not been carried out before. Overall, our approach not only embraces cross-disciplinary links; it, moreover, serves as a reminder of an all-embracing evolutionary history, especially with regard to a ubiquitous photoreceptive 'clockwork-blue' in marine and terrestrial vertebrates.  相似文献   
435.
Society's growing interest in environmental issues requires the production of reliable information for policy-makers, stakeholders and society in general. This information must be based on accurate data produced by qualified laboratories and data need to be comparable between numerous laboratories for joint assessments, e.g. in International Conventions. The Marine Environment Laboratories of the International Atomic Energy Agency has been providing Quality Assurance services to laboratories involved in marine radioactivity studies for the past 30 years. This has included training, organization of laboratory intercomparison exercises, production of Reference Materials (RMs) and more recently, production of Certified Reference Materials (CRMs) that comply with relevant ISO standards. Here, the overall process of Certification of Reference Materials is reviewed, past work summarized and future needs of marine radioactivity laboratories briefly discussed.  相似文献   
436.
Despite the popularity of marine protected areas (MPAs) as a management tool, increasing evidence shows that many fail to achieve conservation objectives. Although several MPAs exist in Sri Lanka, most are not managed, and resource extraction and habitat degradation continue unabated. At present, the declaration and management of MPAs is carried out without adequate consideration of the ecology, socioeconomic realities, or long-term management sustainability. Managers have focused more toward the creation of new legislation and protected areas rather than ensuring the implementation of existing regulations and management of existing protected areas. Poor coordination and a lack of serious political will have also hindered successful resource management. As in other developing countries, MPA managers have to contend with coastal communities that are directly dependant on marine resources for their subsistence. This often makes it unfeasible to exclude resource users, and MPAs have failed to attract necessary government support because many politicians are partial toward the immediate needs of local communities for both economic and political reasons. A more integrated approach, and decisions based on the analysis of all relevant criteria combined with a concerted and genuine effort toward implementing strategies and achieving predetermined targets, is needed for effective management of MPAs and the sustainable use of marine resources in Sri Lanka.  相似文献   
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