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121.
海洋生态损失补偿指用海者履行海洋生态环境资源有偿使用责任,对因开发利用海洋造成的海洋生物资源价值和生态系统服务价值损失进行的资金补偿。文章介绍了海洋生态补偿制度的建立过程,梳理了山东省海洋生态补偿新旧标准的演变过程,对山东省海洋生态补偿标准的实施进行了探讨,并分析了山东省海洋生态补偿资金征收的经济效率。结果表明,按照旧标准,只考虑对海洋生物资源损失的补偿,每公顷用海所缴纳的生态补偿资金为8.143 3万元;按照新标准,考虑对经济生物资源和生态系统服务损失的补偿,每公顷用海应缴纳的生态补偿资金为12.043 9万元,比旧标准提高了48%。补偿标准提高,虽然增加了企业的用海成本,但还只是补偿了企业用海所造成生态损失的1/4左右,还有3/4的生态损失没有要求企业补偿,需要国家财政增加生态修复投入。山东用海生态损失补偿政策的实施,很好地发挥了环境经济政策的效果;企业主动缩减围填海等用海面积,采用环境友好的用海方式,既节约了企业用海成本,又减轻了对海洋生态环境的损耗。在全国推广山东的开发用海生态补偿制度和标准,可以有效地引导企业理性用海、集约高效用海,助力海洋产业绿色转型,体现生态文明入宪的重大意义。  相似文献   
122.
This paper examines key factors used in protecting the migratory North Atlantic right whale within the context of a marine protected area (MPA) system, using the Grand Manan Whale Conservation Area, in New Brunswick Canada, as a case study example. Designated as a conservation area in 1993, before the Oceans Act came into effect, the Grand Manan conservation area currently does not form part of the Canadian network of MPAs. Given the possibility that MPA designation may occur, the paper examines factors that should be considered in meeting International Union for Conservation of Nature (IUCN) MPA design criteria and IUCN evaluation model requirements. An MPA evaluation framework based on an IUCN evaluation model (Hockings et al., 2000 [1]) is designed to assess the effectiveness of an MPA in protecting a migratory right whale. Case study results indicate that current management and research activities for the Grand Manan conservation area address most governance, biophysical and socio-economic issues under an IUCN evaluation framework. On a site basis, it is recommended that the Grand Manan conservation area be designated as a component of the Canadian network of MPAs and that regulations be developed and implemented under the Species at Risk Act to clearly define activities considered damaging or destructive to right whale critical habitat. Recommendations also suggest the preparation of a combined site management-action plan for the Grand Manan conservation area indicating how activities specified in North Atlantic Right Whale Recovery Strategy will be implemented locally. On a regional and international basis, recommendations call for an internationally coordinated and integrated approach to right whale protection within the context of a network of designated critical habitat areas. Recommended activities include: continued Canadian participation in cross-border research and actions to mitigate threats to the right whales over their migratory range; development of a regional right whale management and monitoring strategy; and designation of additional critical habitats in national/international waters. It is further recommended that the evaluation framework developed by this paper be used as a model in assessing the conservation and management effectiveness of MPAs protecting other migratory marine species.  相似文献   
123.
This paper reviews the evidence of the impacts of marine management interventions on human development and well-being reported in marine management literature in the past two decades. Documents dealing with fisheries, aquaculture, marine conservation and coastal zone management are assessed in terms of the methodologies used, the human development dimensions considered, and the results reported. The choice of dimensions for defining human development in this literature is contrasted with proposals from the literature on the capability and human development approaches. Possible areas for future research are discussed.  相似文献   
124.
The Padu system of South Asia has received growing attention as an example of customary marine tenure that has survived despite rapid development and change throughout the region’s fisheries. This paper describes the Padu system as it functions at Pulicat lagoon, India, where it has enjoyed decades of legitimacy amongst its members, and has contributed to sustainable fishing. Recently, however, the Padu system has become unstable, driven by pressures of an expanding fishing population, reduced access to fishing grounds and a growing ‘shared poverty’. In spite of this, fisher loyalty to uphold the Padu system remains strong. This raises questions about the broader social, political and cultural meanings of Padu, which extend beyond access to a lucrative fishery. The paper highlights a trade-off between the benefits received through Padu membership at a societal level through collective action, and the individual costs of partaking in ‘shared poverty’, which is inherently distributed unequally amongst fishing families. The paper concludes with a discussion on the future of the Padu system in Pulicat, drawing from evolutionary pathways of other Padu systems in the region. It is suggested that, in the Pulicat case, the high social values attributed to the Padu system, alongside complex power structures, may hinder institutional adaptation.  相似文献   
125.
Responses of governance systems to change in coastal and marine ecosystems vary from country to country around the globe. Lessons can be learned from country specific case studies, as national governments strive to adapt and respond to issues of concern. This short paper highlights the benefits of a country-specific, special edition of Marine Policy, with a focus on Ireland. Despite the uniqueness of socio-ecological setting, many of the issues faced by policy makers in Ireland, such as the reconciliation of economic development and conservation needs, are shared elsewhere. This special edition was produced at the end of the ‘Celtic Tiger’ in Ireland. As a result, it reflects an era when economic development was very much a priority. The same period represented an unparalleled investment in marine science since the foundation of the State in 1922. Despite this, the papers in the Special Edition point to varying degrees of progress in policy integration and implementation. Papers covering a range of sectors (fisheries, ocean energy, conservation and fisheries) and disciplines (economics, science and management) will be of interest to academics, policy makers, students and practitioners of marine policy.  相似文献   
126.
Islands are often considered to be a priority for conservation, because of their relatively high levels of biodiversity and their vulnerability to a range of natural and anthropogenic threats. However, the capacity of islands to conserve and manage biodiversity may depend upon their governance structures. Many island states are affiliated to other countries through an ‘overseas territory’ status, which may provide them with access to resources and support mechanisms, but which may also influence the capacity for local-scale management of environmental issues. The United Kingdom has 12 island Overseas Territories (UKOTs), most of which support biodiversity of high conservation concern. This study investigates perceptions of current and future threats to marine ecosystems and constraints to environmental protection on the six Caribbean UKOTs, through semi-structured interviews with officials from UK and UKOT government departments and non-governmental organisations. Coastal development, pollution and over-fishing were perceived as threats of most concern for the next decade, but climate change was perceived as by far the greatest future threat to the islands' marine ecosystems. However, a series of common institutional limitations that currently constrain mitigation and conservation efforts were also identified, including insufficient personnel and financial support, a lack of long-term, sustainable projects for persistent environmental problems and inadequate environmental legislation. These findings highlight the need for regional cooperation and capacity-building throughout the Caribbean and a more concerted approach to an UKOT environmental management by the UK and UKOTs' governments.  相似文献   
127.
Abstract

The distributions of infaunal Peracarida (Crustacea) and their correlation with sediment type, tidal height, and degree of exposure were studied in winter (June) at five beaches on Stewart Island, New Zealand. The beaches were selected lo cover a range of exposures to wind and wave action and substrate sorting. Substrate and infauna samples were taken at four tidal levels from each, with a 0.0625 m2 quadrat.

Sieve separation and statistical analysis of the substrate samples indicated predominantly sand‐sized particles from all beaches, with median diameters in the range +1.52 to +2.92 ? (phi) units. Substrates were well sorted throughout the size range: ? quartile deviation ranged from 0.26 to 0.71, skewness from —0.18 to +0.07 ?.

Peracarid fauna was generally abundant, with a maximum of 29 136 per m2sampled in a more sheltered beach. Cumacea was the most abundant group, followed by Amphipoda, Isopoda, and Tanaidacea; dominance followed a similar sequence, being 78%, 19%, 2% and 1% respectively. Frequency of occurrence at the 19 stations was headed by Amphipoda (100%), with Isopoda 53%, Cumacea 32% and Tanaidacea 11%.  相似文献   
128.
根据2009-04—2010-02隔月6个航次桑沟湾9个调查站位贝类养殖区有机氯(OCPs)、有机磷(OPPs)农药残留和麻痹性贝毒(PSP)的调查资料,分析了它们在该海域海水中、表层沉积物中和主要贝类(栉孔扇贝、太平洋牡蛎和菲律滨蛤仔)体内的含量水平,就农药残留及贝毒污染对海洋环境质量的影响进行综合评价和类别划分,并对主要食用贝类中农药残留和贝毒的暴露水平进行健康风险评估。结果表明,桑沟湾贝类养殖区海水质量、沉积物质量和养殖贝类质量水平范围为1~2级,平均分别为2级、1级和1级,养殖生态环境综合质量水平为2级;总体上,该海域海洋环境综合质量处于良好水平,贝类产区生态环境质量为1类区(清洁区)。即该海域农药残留及贝毒污染对海洋环境质量影响较小或无明显影响。另外,针对食用桑沟湾贝类水产品的消费人群进行了农药残留及贝毒污染的健康风险评估,结果表明调查人群食用贝类中OCPs中的HCHs和DDTs、OPPs中的马拉硫磷和甲基对硫磷、PSP的日摄入量分别为0.75,2.11,0.19,0.09和1.22μg/(人·d),其摄入量低于ADI的推荐限值,因此桑沟湾主要食用贝类中农药残留及贝毒污染的健康风险处于安全范围。  相似文献   
129.
Recent changes in marine policy in Panama are closely related to sustained expansion of the Panamanian economy in the past ten years. Important drivers of economic growth such as the Panama Canal expansion, tourism, and real estate development directly involve marine and coastal areas. Therefore, maintaining the quality of these environments, as well as the sustainability of the human communities that depend on them, calls for the implementation of adequate management and planning policies. In light of a complex history of marine and coastal policy in Panama, current institutional restructuring processes, and a growing recognition of the importance of marine and coastal geographies, the authors aim to document the current status of, and community response to, marine and coastal policy in Panama, analyzed in terms of three important cross-cutting sectors: tourism, fishing, and conservation. To do so, the authors introduce two case studies: one in the Pearl Islands Archipelago and one in Bocas del Toro, each with varying degrees of participation or involvement in each sector, to illustrate the range of adaptations to change occurring in coastal communities. Based on an in-depth policy analysis and the case studies, the authors suggest that there are important administrative and structural gaps in the legislation and institutions that enforce them, as well as a lack of integration across institutions. In particular, the authors highlight the lack of clear marine and coastal property regimes as an obstacle to the implementation of integrative marine policies in Panama.  相似文献   
130.
Luminescence dating has long been used for chronological constraints on marine sediments due to the ubiquitous dating materials (quartz and feldspar grains) and its applicability over a relatively long time range. However, one of the main difficulties in luminescence dating on marine sediments is partial bleaching, which causes age overestimations. Especially, partial bleaching is typically difficult to be detected in the fine grain fraction (FG) of marine sediments. The recently developed feldspar post-IR IRSL (pIRIR) protocol can detect non-fading signals and thus avoid feldspar signal instability. In the current study, fine grains were extracted from a gravity core in the northern Sea of Japan, and the aim is to test the feasibility of using different luminescence signals with various bleaching rates to explore the bleaching conditions of fine grain fraction in marine sediments. The results suggest that the quartz OSL signal and polymineral pIRIR signals at stimulation temperatures of 150 °C and 225 °C (pIRIR150 and pIRIR225) of FG were well bleached prior to deposition. The OSL ages were used to establish a chronology for this sedimentary core and the resulting age-depth relationship is self-consistent and comparable with radiocarbon dates. We conclude that different luminescence signals with various bleaching rates can be used to test the bleaching conditions of fine grain fraction in marine sediments; and the luminescence dating can be applied to marine sediments with great potential.  相似文献   
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