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341.
The designation of marine protected areas (MPAs) may have intense social and economic effects on human communities. Driven by overarching global and European policies and national legislations, current systematic conservation planning in the UK and France requires an ecosystem approach that takes into account not only nature but also the human activities that take place in an area. Here, we identified a set of 64 socioeconomic variables potentially relevant for marine and coastal stakeholders in a European context and a comprehensive set of 20 marine and coastal stakeholder categories. Ninety national organisations in the UK and France belonging to those categories and potentially affected by/interested in the designation of multiple-use MPAs were identified and surveyed. Results show that environmental NGOs, research centres, local councils, managing agencies and statutory nature conservation bodies perceived that they are positively affected by these MPAs, whereas fishers’ organisations, shipping and aggregate industrial organisations and recreational organisations perceived to be chiefly negatively affected by MPAs. On average, the ecological effects of multiple-use MPAs are perceived as ‘largely positive’, though 30% of respondents did not perceive any positive ecological effects from these MPAs. The social, economic and cultural effects of such MPAs are perceived as ‘moderately positive’. Most respondents perceived broad range (>10 km) and permanent ecological, social, economic and cultural effects from multiple-use MPA designation suggesting high societal expectations towards these areas. However, only five variables were perceived to vary in intensity after the designation of multiple-use MPAs: ‘research’, ‘environmental performance by citizens, businesses and towns’, ‘number of green businesses’, ‘tourism’ and ‘economic activities’. The most important ‘social’ variables for stakeholder organisations referred to local populations’ engagement with the MPA, tourism and research. The most important ‘economic’ variables were linked to fishing, shipping and aquaculture activities. These variables highlight relevant topics to be considered in MPA planning, designation and management processes, especially in the UK and France. There were statistically significant differences in the ratings of socioeconomic variables between many organisations belonging to the same intuitive stakeholder categories, suggesting the importance of including as wide a range of stakeholder organisations as feasible in MPA socioeconomic-related processes. Our methods and findings can help to inform and streamline ongoing and future participatory MPA planning, management and monitoring processes in Europe and in other regions with similar socioeconomic characteristics.  相似文献   
342.
黄俊  衣俊  强丽媛  程金平 《环境科学》2016,37(5):1968-1977
纳米银由于其独特的抗菌特性广泛应用于工商业领域.通过研究3种不同粒径和包裹物的纳米银对典型海洋微藻中肋骨条藻(Skeletonema costatum)的毒性效应,进一步丰富纳米银对藻类毒性效应及其作用机制的认识.结果表明3种纳米银对硅藻细胞生长都有不同程度的生长抑制效应,其毒性大小依次为10 nm-OA10 nm-PVP20 nm-PVP.在细胞毒性方面,相同粒径的聚乙烯吡咯烷酮(PVP)包裹的纳米银比油胺包裹(OA)的纳米银毒性更小;而相同包裹物的10 nm和20 nm两种尺寸的纳米银的毒性效应主要取决于其在水环境中的粒径和浓度,在浓度小于500μg·L~(-1)时,大粒径的纳米银毒性更大;在浓度≥500μg·L~(-1)时,小粒径的纳米银毒性更大.在光合毒性方面,50μg·L~(-1)的10 nm-PVP显著上调3Hfcp A的表达(P0.05)和显著下调D1的表达(P0.05),10 nm-OA在浓度为500μg·L~(-1)显著上调3Hfcp A的表达(P0.05),而20nm-PVP处理组没有显著性变化,说明光合作用相关基因的表达对小粒径PVP包裹的纳米银更敏感.本研究结果表明,纳米银对海洋微藻的毒性是由粒径大小、包裹物类型、暴露介质以及暴露浓度等多方面因素共同决定的.纳米银的粒径越小毒性越大,粒径对纳米银的毒性效应影响很大;而包裹物通过影响纳米银在水介质中的粒径大小间接影响纳米银的毒性效应.  相似文献   
343.
福建省九龙江江东库区沉积物微藻分布研究   总被引:1,自引:0,他引:1  
沉积物既是营养盐的储存库,也是藻类的休眠场所.本研究以九龙江北溪江东水库为研究对象,于2011年4月、6月、9月、12月采集表层沉积物,对其营养盐含量、表层沉积物微藻分布及丰度进行分析.结果表明,沉积物大部分为粉砂质粘壤土,该区域沉积物总碳含量为9140.2~17760.4 mg·kg~(-1),总氮含量为950.0~1600.4 mg·kg~(-1),总磷含量为483.7~856.2 mg·kg~(-1).库区表层沉积物微藻细胞丰度范围在7.41×105~2.17×106cells·g~(-1)底泥(以干重计),主要为硅藻门和绿藻门,分别占微藻比例的45.52%~86.42%和5.96%~35.55%.沉积物微藻总丰度与上覆水体浮游植物总丰度及隐藻、裸藻丰度呈显著负相关,反映了沉积物微藻对上覆水体浮游植物的影响.沉积物中蓝藻、隐藻、甲藻孢囊丰度分别与水温呈显著负相关,分别与溶解氧呈显著正相关,因而冬季沉积物中有相对高的微藻丰度.沉积物微藻丰度与含水率、粉粒分别呈显著性正相关,反映了沉积物微藻沿着水流方向的积累.  相似文献   
344.
Climate change science can trace its origins back to the early 19th Century although interest really took off in the 1980s, when public interest and research activity proliferated as the potential negative effects of global warming became clear. The impacts of climate change on the marine environment was receiving little attention at this time, but in recent years has started to “catch up” both in terms of research activity and public and policy interest. In the UK, the Marine Climate Change Impacts Partnership (MCCIP) has played a key role in transferring the emerging evidence base on marine climate change impacts to decision makers through the development of climate change report cards. Since publishing its first card back in 2006, the MCCIP cards have become established as the principal source of marine climate change impacts evidence for policy makers in the UK, and similar approaches have been adopted elsewhere. Here we broadly describe how the climate change evidence base has evolved over time, with a focus on the marine evidence base, and the approach adopted in the UK by MCCIP to rapidly transfer this evidence to end users. The SIIRMS model developed by MCCIP to ensure integrity and independence in the scientific translation process is explored, along with wider lessons learnt along the way (e.g. about communicating uncertainty) and the impact MCCIP has had on informing decision making.  相似文献   
345.
采用普通小球藻(C.vulgaris)作为实验藻种,搭建缺氧MBR-微藻膜反应器(缺氧MBR-MMR)耦合系统处理海水养殖废水,前置缺氧MBR用于有机物、NO-3-N和NO-2-N的降解,释放的NH+4-N进入MMR用于微藻生长而得到去除,考察协同处理效能和微藻采收情况,探究膜污染行为.反应系统共运行91 d,对NO-3-N和NH+4-N的去除率分别达到90.0%和88.0%以上,对PO3-4-P和TOC的平均去除率分别为49.4%和84.7%.普通小球藻在进行连续采收的情况下,能以平均浓度为9×107个·mL-1的生物量稳定运行,实现了较好的去除效能和资源化利用.通过红外光谱和三维荧光光谱分析,MMR内造成膜污染的主要物质是色氨酸类蛋白质和腐殖酸类物质,与缺氧MBR内膜组件相比污染...  相似文献   
346.
汪芳  葛蔚  柴超  孟祥霞 《环境科学》2013,34(8):2992-3001
以东海原甲藻为优势种群的浮游微藻作为研究对象,在不同氮浓度(0、128、512μmol·L-1)和磷浓度(0、8、32μmol·L-1)下培养,研究了氮、磷浓度对东海原甲藻优势种群生化组成和吸附2,4,4’-三溴联苯醚(BDE28)和2,2’,4,4’-四溴联苯醚(BDE47)的影响,分析了东海原甲藻优势种群对BDE28和BDE47的吸附量与生化组成的相关性.结果表明,氮浓度为0μmol·L-1时,单位细胞对BDE28和BDE47的吸附量分别为2.2 ng·(106cells)-1和2.9 ng·(106cells)-1,是氮为128μmol·L-1和512μmol·L-1浓度的1.3~1.9倍.不同氮浓度之间单位体积藻液吸附量和对BDE28和BDE47的吸附百分数均没有显著差异,单位体积藻液吸附量范围为0.160~0.184 ng·mL-1,吸附百分数为80.2%~92.1%.磷浓度为0μmol·L-1时,单位细胞BDE28和BDE47的吸附量分别为7.6 ng·(106cells)-1和8.4 ng·(106cells)-1,是磷为8μmol·L-1、32μmol·L-1浓度时的5.4~6倍,单位体积藻液吸附量和吸附百分数在不同磷浓度间未出现显著差异,单位体积藻液的吸附量为0.167~0.194 ng·mL-1,吸附百分数为80.2%~93.2%.相关性分析表明,氮浓度与单位细胞BDE28和BDE47的吸附量呈负相关,磷浓度与单位体积吸附量和吸附百分数呈正相关;同时,吸附量与总脂呈正相关关系.氮、磷浓度导致东海原甲藻优势种群细胞的生化组成发生变化,进一步引起对BDE28和BDE47吸附的变化.  相似文献   
347.
Mankind needs to use the resources and opportunities offered by the marine environment while protecting ecological processes and systems. This is the foundation for sustainable development, which can only be achieved by adopting an appropriate management approach. Whether internationally or at a regional scale, successful management of marine ecosystems needs to be based on a scientifically robust approach to monitoring environmental change. Within such a framework, the conservation of marine biological diversity is problematic, as many conventional measures of diversity are not appropriate for measuring the types of change that require management. New indicators are required and in this paper we summarise some of the current methodology being used to derive such indices, which may be used to evaluate the effectiveness of marine stewardship initiatives. Through a series of examples we demonstrate the application of the taxonomic distinctness indicator of biodiversity to marine environmental assessment and its development towards becoming an operational tool.  相似文献   
348.
Increased development pressures on the marine environment and the potential for multiple use conflicts, arising as a result of the current expansion of offshore wind energy, fishing and aquaculture, dredging, mineral extraction, shipping, and the need to meet international and national commitments to biodiversity conservation, have led to increased interest in sea use planning with particular emphasis on marine spatial planning. Several European countries, on their own initiative or driven by the European Union's Marine Strategy and Maritime Policy, the Bergen Declaration of the North Sea Conference, and the EU Recommendation on Integrated Coastal Zone Management, have taken global leadership in implementing marine spatial planning. Belgium, The Netherlands, and Germany in the North Sea, and the United Kingdom in the Irish Sea, have already completed preliminary sea use plans and zoning proposals for marine areas within their national jurisdictions. This paper discusses the nature and context of marine spatial planning, the international legal and policy framework, and the increasing need for marine spatial planning in Europe. In addition, the authors review briefly three marine spatial planning initiatives in the North Sea and conclude with some initial lessons learned from these experiences.  相似文献   
349.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years, the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences of development plans are seldom considered). Some international conservation organizations are testing promising new approaches to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources, they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major role in the design and implementation of any fishing management actions.  相似文献   
350.
N  = 1475) traveling with tourism operations of different sizes who traveled to different sites completed surveys. Results indicated that snorkelers who traveled with larger operations (more people and infrastructure) differed from those traveling with smaller operations (few people and little on-site infrastructure) on benefits received and in the way that specific conditions influenced their enjoyment. Benefits related to nature, escape, and family helped to define reef experiences. Conditions related to coral, fish, and operator staff had a positive influence on the enjoyment of most visitors but, number of people on the trip and site infrastructure may have the greatest potential as setting indicators. Data support the potential usefulness of visitor input in applying the LAC concept to a marine environment where tourism and recreational uses are rapidly changing.  相似文献   
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