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1.
本文以2013-2017年我国鱼类、甲壳类、贝类、藻类、其他类产品海水养殖规模及产量的分析为基础,有别于现有文献关于我国海水养殖业发展现状的分析,创新性地使用比较优势模型并测算专业化系数,分析我国海水养殖结构特点,明确10个沿海省市的优势海水养殖产品及其养殖专业化程度,从而有针对性地指出我国海水养殖结构的优化方向。文章结果表明:(1)我国五类海水养殖产品的产量均呈上升趋势,且贝类的产量始终最高;海水养殖总面积有所下降,其中贝类产品的养殖面积虽逐年减少,但始终位于第一。(2)山东、福建、广东三省的海水养殖总产量、养殖规模和单产均位于全国10个沿海省市的前列。(3)10个沿海省市分别拥有自己的优势海水养殖产品,但只有海南充分发挥优势实现专业化生产。对此,我国应继续优化海水养殖产品布局,促进各省市对自身比较优势产品的规模化生产,从而推动全国海水养殖产业的高效专业化发展。  相似文献   

2.
海上养殖业对粮食安全有着至关重要的作用。然而,海上养殖的无序扩张和开发,阻碍了海上交通,同时也造成了海洋环境问题。为及时、准确地获取海上养殖信息,满足海岸带调查以及推进海上养殖规范化、科学化,提出一种基于谷歌地球引擎(Google Earth Engine, GEE)平台实现长时间序列下海上养殖区信息快速提取的方法。本研究构建了一个基于随机森林分类的海上养殖区信息提取模型,该模型综合利用了Sentinel 1卫星SAR影像数据的VV和VH极化波段,以及Sentinel 2卫星的多光谱影像数据。此外,模型还融合了4个用于增强养殖区特征的指数,以提高养殖区域信息提取的准确性和效率。这种方法的应用旨在优化海上养殖区的识别过程,通过精确分析和利用不同数据源的互补优势,展现了〖JP2〗遥感技术在海洋养殖监测领域的巨大潜力。本研究对2017—2021年平潭县海上养殖区域进行判定与提取,实验结果表明,以养殖密度较低,养殖特征不明显为特征的海上养殖区,基于GEE平台的海上养殖区信息提取方法精度在90%以上,表明在复杂水体背景下对养殖区快速识别取得较好的效果,可为海上养殖科学规划与规范化管理提供有效的参考依据。  相似文献   

3.
This paper reviews the principal marine and coastal policy changes in England since 1999. The key changes identified are the establishment of a strategic national marine and coastal policy direction, new marine legislation and institutions, the emergence of a marine planning framework, the consolidation of Integrated Coastal Zone Management approaches to coastal governance, the establishment of a Marine Protected Area network, and the decline of coastal partnerships. The European Union, UK National Government, and devolved administrations are identified as key influences on the governance evolution and their relative contributions are discussed. It is concluded that the English marine and coastal governance context has evolved significantly since 1999 and that the new framework, if implemented successfully, represents a genuine step towards an integrated governance framework for England's coasts and seas.  相似文献   

4.
Recently, aquaculture has generated worldwide interest as a result of the overexploitation of wild stocks combined with a growing international demand for fish and seafood products. Wild fish attracted to the marine fish farms, together with the presence of the farmed fish, are powerful attractants to predators that normally feed on similar or identical fish stocks in nature. This 9‐year study describes for the first time in Mediterranean waters the temporal variability of mammalian and avian predators in a coastal fin fish farm. In all, 99 months (1062 days during 36 consecutive seasons) were spent in the field. By examining the results of this study, it is clear that species as seagulls, shags, bottlenose dolphins and grey herons (considered to cause economic loss in aquaculture owing to direct predation) interact regularly with the fish farm. Although bottlenose dolphins and grey herons were not the most important of all predator species, predatory interactions with the fish farm occurred with what seems to be increasing regularity. Another result observed is the possible bottlenose dolphins’ attraction caused by the harvesting operations in the fish farm. The fish farm offers an alternative food source for predators; hunting at fish farms usually requires less effort on the part of the predator, and becomes a more attractive option than hunting wild fish over wide ranges. During the period of this study, individually identified dolphins feeding were regularly observed feeding on discarded fish from fish farm workers during harvesting operations, supporting the possibility that some individuals are habituated to this food supply. Based on the evidence presented in this paper, it is recommended that strategies for the management of both the aquaculture industry and marine mammal populations should take the results of this study into consideration.  相似文献   

5.
环境因子对海蜇生长发育影响的研究进展   总被引:1,自引:0,他引:1  
<正>海蜇(Rhopilema esculenta Kishinouye)隶属于刺胞动物门(Cnidaria),钵水母纲(Scyphozoa),根口水母目(Rhizostomeae),根口水母科(Hizostomadae),海蜇属(Rhopilema)[1]。海蜇为进化比较保守的两胚层动物[2]。丁耕芜等[3]首次报告了海蜇的整个生活史。海蜇生活史具有刺胞动物门典型的世代交替特征,分为两个世代:水螅体世代和水母体世代。在水螅体世代整个过程中,海蜇螅状体于海底基质上营固着生活,以无性生殖  相似文献   

6.
While several studies point at off-shore aquaculture as a possible source of impacts on the local marine environment, very few have analysed its effects at large scales such as at the bay, gulf or basin levels. Similar analyses are hampered by the multiple sources of disturbance that may concomitantly affect a given area. The present paper addresses these issues taking the Gulf of Castellammare (Southern Tyrrhenian Sea) as an example. Nitrogen (N) and phosphorous (P) loads were calculated for the period 1970-2007, and compared to chlorophyll-a concentration as measured inside and outside the Gulf over the same period. Results indicate that N and P catchment loading has constantly decreased because of improved environmental management. Nevertheless, nutrient concentration in the Gulf has steadily increased since the establishment of aquaculture facilities in 1999. Chlorophyll-a concentration followed this trend, showing a marked increase from 2001 onwards. In the same period, chlorophyll-a concentrations measured inside and outside the Gulf have significantly diverged. As all the other possible causes can be ruled out, aquaculture remains the sole explanation for the observed situation. This paper demonstrates for the first time ever that off-shore aquaculture may affect the marine ecosystem well beyond the local scale and provides an additional element of concern to be kept into consideration when allocating oceans' space for new fish-farming activities.  相似文献   

7.
Bangladesh has vast coastal and marine resources along its south edge. Due to the geographical position and climatic condition, the coastal area of the country is known as one of the highly productive areas of the world. Bangladesh is rich not only in terms of its vast water areas but also in terms of the biological diversity. One of the unique features of the coastal areas is the influence of the mangrove forests, which support a high number of fishes and other commercially important aquatic organisms. The biological and ecological values of the Bay of Bengal have been pointed out by many authors. The coastal and marine fisheries have been playing considerable roles not only in the social and economic development of the country but also in the regional ecological balance. A large number of commercially important fishes have long been exploited which are of high export values. Shrimp aquaculture has become a highly traded export-oriented industry for the last few decades. In spite of having bright prospects, marine aquaculture on a commercial basis as well as marine stock enhancement and sea ranching are yet to be developed. The marine fisheries sector has been suffering from chronic disintegration and mismanagement that have led to many consequences. Most of the commercially important fish stocks are either overexploited or under threat. Marine pollution has reached a level that could create an unmanageable situation in the near future; coastal shrimp farming has generated considerable debates due to its adverse environmental and socioeconomic impacts. The Bay of Bengal and its coastal areas are one of the most poorly studied areas of the world although it possesses high potential for further stock improvement. Proper attention is needed in every aspect of exploitation, handling and processing, export and marketing as well as in biological and institutional management strategies. The Bay of Bengal has been increasingly important for local development as well as for a global perspective. The coastal and marine fisheries of the Bay of Bengal are briefly reviewed in this paper to provide a salient feature of the available information and resource base and to identify future research and management needs.  相似文献   

8.
The growing aquaculture industry is projected to feature ever more prominently in the lives and economies of rural coastal communities in Atlantic Canada and around the world. Both private industry and government have a responsibility to ensure employment opportunities created in aquaculture take place in healthy, safe environments. However, systematic occupational health and safety (OHS) research within this industry, an important prevention tool, is still in its infancy. With particular emphasis on marine aquaculture in Atlantic Canada, we provide a detailed outline of the structure of the industry from feed production through to processing, identify potential OHS hazards associated with each of these activities and make recommendations for future research and action.  相似文献   

9.
Guatemala's rich coastal and marine biodiversity provides essential ecosystem goods and services to local residents and the national economy through artisanal and commercial fisheries, aquaculture, port exports and, to a lesser extent, tourism. As in many other countries, national policies emphasise the significance of marine conservation and marine resources, primarily through implementing marine protected areas (MPAs). However, this assumes that governance, as reflected in legal, institutional and organizational frameworks, political capacity and human resources is sufficiently developed to ensure MPAs meet these goals. These issues are explored through presenting the first detailed analysis of coastal and marine governance in Guatemala. The research highlights a range of barriers to good governance which restrict the extent to which MPAs can function effectively. Recommendations are made which can capitalise upon the potential for locally managed marine areas as a means to facilitate the improved governance of coastal and marine resources in Guatemala.  相似文献   

10.
本研究选取海洋渔业固定资产投资额、海洋渔业劳动力数量、海洋捕捞生产率和海水养殖生产率4个变量,提出影响因素假设;选取我国沿海地区海洋渔业的面板数据,进行模型设定和数据检验。通过确定变截距固定效应的回归模型形式,对模型进行估计和分析,结果表明:海洋渔业固定资产投资额、海洋渔业劳动力数量和海水养殖生产率与海洋渔业经济呈正相关,影响度由大到小依次为劳动力因素、资本因素和生产率因素,而海洋捕捞生产率的影响基本不显著;各地区海洋渔业经济发展程度不一,且差距明显。在此基础上,提出促进我国海洋渔业经济发展的对策建议:加强专业人才集聚;提高资本投入,完善资本市场建设;提高海水养殖生产率,数量和品质兼备;推动区域一体化联动发展。  相似文献   

11.
This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%–28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of coastal management regulation, for instance in the implementation of the European Marine Strategy Framework Directive.  相似文献   

12.
The effects of recreational fishing on marine stocks and ecosystems have raised global concern in recent years. In Argentina, Southwest Atlantic, angling, netting and spearfishing of coastal bony fishes, sharks, rays and chimaeras are very popular pastime activities with more than 50 years of history. Despite the perceived traditional and economic relevance of these activities in the country, marine recreational fisheries were largely unregulated, and no official fisheries monitoring programs at the national level have been ever put in place. Except for a few particular systems for which some catch-and-effort data were collected by research institutions and non-governmental organizations, no comprehensive surveys aimed at describing the ecological, social or economic aspects of these fisheries have been made. Here, an updated review of the regulations in place for marine recreational fisheries along the Argentine coastline is presented. Of the five coastal provinces encompassing ca. 8400 km and about 20 latitude degrees (~36°S to 55°S) of coastline, only Buenos Aires province has a thorough legislation for its whole territory, which includes 15 protected areas. In the remaining provinces, the regulations for marine recreational fisheries are limited to a few protected areas (seven out of 37 coastal areas under provincial, national or shared jurisdiction). This lack of legislation encourages alleged recreational fishers to develop small-scale commercial fishing operations that are neither controlled nor monitored as such, contributing to the overexploitation of some key coastal stocks.  相似文献   

13.
Biological invasions continue to increase around the world, with impacts on many coastal marine systems. Here we review the South African marine invasion literature which, despite the field being relatively new, has grown to have significant presence in both the local and international arenas. Of the 79 papers reviewed, 70% focused on the establishment and spread of alien species, with modes of transport and introduction largely overlooked. An emphasis was also apparent towards field studies, in particular survey work, with few experimental studies. The overwhelming majority of papers focused on a single species, the Mediterranean mussel Mytilus galloprovincialis, reflecting the scale of this invasion and the tractable nature of rocky shores as study systems. With the exception of this one species, the impacts of marine alien species have rarely been quantified. We suggest that future research extends the taxonomic coverage of present work and develops a better understanding of the mechanisms of introduction, establishment and spread of marine alien species. Through an experimental approach, the drivers of altered ecological patterns and processes resulting from invasions should be addressed, providing insight into associated impacts. This approach will maintain the local applicability and international relevance of South African marine invasion research.  相似文献   

14.
海岸线作为海洋与陆地的分界线,是海域管理的重要界限和基础地理数据,也是地图编绘、海洋调查和海岸带演变研究的重要内容,准确掌握其位置、长度等信息,是提高海域管理科学化水平的必不可少的环节。文章结合广东省海岸线修测实际工作中发现的问题,对围海养殖区海岸线界定方法进行探讨。针对养殖区已进行土地确权的情况进行深入分析,并提出:以自然属性为主要依据判定海岸线位置;承认土地权利人的权利在先;围海养殖区的海岸线统一以靠陆一侧的外边缘线进行界定等解决方案。期望可以为海岸线修测和海域管理提供有益的参考。  相似文献   

15.
The management of marine ecosystems requires adequate knowledge of both environmental and human dimensions, as well as their interrelationships. In this study, the aquaculture and fisheries activities are analyzed in one of most important fishing regions in Europe, Galicia (NW Spain). In particular, the intensity and characteristics of the fishing dependency are evaluated in terms of income and employment. Thus, nine marine economic activities for nine Maritime Zones have been defined, considering the social and economic relevance of the provided ecosystem services to these communities. This paper highlights the entire Galician coast as fishing-dependent, independently of the urbanization level. Furthermore, the contribution of different fishery segments to the income and employment of these coastal communities is reviewed, including fluctuations on whether the activity is small or large-scale. Finally, this study establishes a strong relationship among the marine activities, which generate most employment, and the regulatory framework of the Regional Government. Therefore, the conclusions are relevant to design and implement policies that affect Galicia׳s Region and all its related marine ecosystems.  相似文献   

16.
Benefits humans rely on from the ocean – marine ecosystem services – are increasingly vulnerable under future climate. This paper reviews how three valued services have, and will continue to, shift under climate change: (1) capture fisheries, (2) food from aquaculture, and (3) protection from coastal hazards such as storms and sea-level rise. Climate adaptation planning is just beginning for fisheries, aquaculture production, and risk mitigation for coastal erosion and inundation. A few examples are highlighted, showing the promise of considering multiple ecosystem services in developing approaches to adapt to sea-level rise, ocean acidification, and rising sea temperatures.Ecosystem-based adaptation in fisheries and along coastlines and changes in aquaculture practices can improve resilience of species and habitats to future environmental challenges. Opportunities to use market incentives – such as compensation for services or nutrient trading schemes – are relatively untested in marine systems. Relocation of communities in response to rising sea levels illustrates the urgent need to manage human activities and investments in ecosystems to provide a sustainable flow of benefits in the face of future climate change.  相似文献   

17.
South Australia is among the regions internationally, where there are currently strong drivers for anthropogenic and ecosystem marine planning decisions. Specifically, South Australia, in both State and adjacent Commonwealth Waters, is currently accommodating increasing interests such as oil exploration by multi-national companies in the Great Australian Bight, implementation of recently declared State Marine Parks, an increased public awareness of marine developments, commissioning of a desalinisation plant, government-focused marine science initiatives, long-standing commercial fisheries, a transparent legislative and political stage, and a relatively new aquaculture industry. Amongst this growing diversity in marine-based activities, a dedicated aquaculture legislative framework was created in South Australia with the commencement of the Aquaculture Act 2001 (the Act) to centralise the legislative processes required to underpin aquaculture regulation and administration. This centralisation has helped to create an effective platform to streamline administrative processes, reduce duplication between various government agencies such as planning authorities and environment protection agencies, and ultimately fostered investment in, and growth of, the South Australian aquaculture industry. As such Aquaculture zone policies are a key strategic management tool for sustainable aquaculture development in South Australia into the future. This paper provides a case study (Aquaculture (Zones – Lower Eyre Peninsula) Policy 2013) of the legislated regional marine planning framework for aquaculture development used in South Australia, with a focus on the key functions and processes that may have broader applications.  相似文献   

18.
The increasing global demand for animal protein is a major ecological concern due to its impacts on land use, climate change, global grain supply and fisheries. One method for harvesting animal protein is to grow marine fish. This is widely practiced in coastal environments, but also leads to environmental problems associated with habitat loss and nutrient loading. One alternative is to move marine aquaculture further offshore, away from coastal land-use conflicts and towards ocean currents, which can efficiently dispose wastes. This concept creates a logistical challenge, however, since operators have to transport large amounts of food, fish and fuel to and from offshore cages on a regular basis and in varied weather conditions. In this paper, we discuss the economic feasibility of using offshore oil and gas platforms as bases for open ocean aquaculture in the Gulf of Mexico. We develop net-present value models of a platform-based operation and describe sensitivity analysis of the model output. We conclude that offshore platform-based mariculture may be commercially viable under favorable assumptions, that its viability requires economies of scale and depends principally on the yield per unit of cage volume achieved. The limitations of the analysis are described.  相似文献   

19.
Marine and coastal policy in the UK has faced a number of significant changes in recent years, most notably the passing of the Marine and Coastal Access Act in 2009. These changes have brought significant challenges and opportunities for all those involved in the management and use of the UK's marine and coastal environment. This new era of marine policy inspired the UK's first Marine and Coastal Policy forum held in June 2011. In this introductory paper the global context of marine policy changes and the themes which emerged from the forum, forming the basis of the articles in this special issue, are outlined. It is concluded that there is a high level of engagement, capacity and willingness of key stakeholders to work collaboratively to address the environmental, social and economic complexities of managing the marine and coastal environment. It is both evident and encouraging that progress is being made and the many challenges faced in this new era give rise to a number of opportunities to develop new ideas and effective mechanisms for finding solutions.  相似文献   

20.
The EU Blue Growth Agenda targets maritime economic activities that have the sea and the coasts as drivers. These activities are supported by marine Ecosystem Services (ES) in combination, or not, with abiotic outputs from the marine natural capital. This paper analyses Blue Growth activities with regards to the demand and supply of marine ES and Good Environmental Status (GES). The results show that marine provisioning ES support aquaculture and blue biotechnology, while blue energy is supported by marine provisioning ES and by abiotic provisioning, and abiotic provisioning supports extraction of marine mineral resources. Maritime, coastal and cruise tourism is supported by cultural marine ES and cultural settings dependent on marine abiotic structures. All these multi-sectoral economic activities depend on healthy marine and coastal ecosystems that are provided by regulating and maintenance ES combined with the abiotic regulation and maintenance by natural marine physical structures and processes. In order to balance concurrent sectoral interests and achieve sustainable use of marine resources there is the need to consider indicators for demand for ES, which are social and economically driven, and for the supply, which are dependent on ecosystems capacity to provide the required marine ES. Some of the actions foreseeing GES are already anticipated in legislation that underpin Blue Growth, whilst others could benefit from additional regulation, particularly in what concern the exploration and exploitation of marine mineral and biological resources. Blue Growth options require navigating trade-offs between economic, social and environmental aspects.  相似文献   

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