Mechanisms for marine regime shifts: Can we use lakes as microcosms for oceans?

Although striking regime shifts have been observed in marine systems, mechanistic explanations for these phenomena remain scarce. Here, we review studies of regime shifts in lakes and compare them to what has been found in marine systems to explore the extent to which lakes can be viewed as microcosms for studying essential ecosystem feedbacks in marine systems. We conclude that despite obvious differences, which have been discussed by several authors, lakes are in fact quite similar to oceans in many aspects. In particular, similar mechanisms may be involved in causing alternative attractors (and thus a tendency to show occasional regime shifts) in both systems. A striking similarity exists between the mechanisms that may have caused massive marine anoxic events in the distant past, and the shift of many deep lakes to a mode of anoxic phosphorus recycling. Biotic interactions are relatively poorly understood in the oceans. However, based on what we know from lakes, we expect competitive interactions and diffuse multi-species interactions to be a common cause of alternative attractors in marine communities. In addition, overexploitation traps are an obvious cause of multiple attractors to be expected in the oceans. These should not be limited to direct effects of human overexploitation. Shifts between overexploited and under-exploited states may happen at various trophic levels. Finally, we conclude from observed patterns and theoretical results that implications of alternative attractors will be quite different in benthic and open ocean systems. Benthic regime shifts might happen easily but can be relatively local. By contrast, open ocean shifts might not arise so easily but tend to be impressive in magnitude and scale when they happen.     

Using normative evaluations to plan for and manage shellfish aquaculture development in Rhode Island coastal waters

As shellfish aquaculture activities grow in the US, researchers, practitioners, resource users, and others have questioned how much development can be accommodated by natural and social systems. In a unique application of the normative evaluation approach to shellfish aquaculture development, this study uses data from a mail survey to (1) examine Rhode Islanders’ support for aquaculture in general and in RI waters; (2) investigate how different features of an aquaculture farm influence normative evaluations; and (3) explore areas of agreement and disagreement among stakeholder groups for social carrying capacities associated with aquaculture in RI coastal waters. Findings demonstrate that respondents do not strictly support or oppose aquaculture development; instead support depends on the waterbody where the aquaculture is occurring, the amount of area used for aquaculture, and ways in which aquaculture is conducted. Social norm curves show that levels of acceptabilities for shellfish aquaculture development in two RI waterbodies decline with increasing levels of aquaculture activities. Comparisons among sub-sets of respondents highlight disagreement among groups on the level beyond which shellfish aquaculture development is no longer acceptable (social carrying capacity). Results from normative evaluation studies can be used in combination with physical, ecological, and biological carrying capacities; management goals and objectives; other resource uses and values; and desired social and ecological conditions to inform policy discussions about shellfish aquaculture development in coastal waters.     

舟山东极岛潮间带贝类生态学初步研究

为了解东极岛潮间带贝类生态状况,为浙江海洋生态系统基本群落结构提供基础资料,于2010年4月至2011年4月的大潮期间,在舟山东极岛潮间带采集贝类,调查了解贝类的种类组成、数量分布、生态特点、多样性情况。研究分析发现,东极岛潮间带贝类33种,隶属3纲7目20科。根据温度适应性质分,东极岛潮间带贝类属于3个类群：广温广布种15种,占45.5%;温带种4种,占12.1%;亚热带种14种,占42.4%。东极岛潮间带贝类四季平均生物量为1541.8 g/m2,由高潮带向低潮带呈递增趋势;四季平均栖息密度为925.2个/m2,以中潮带最高,向高潮带和低潮带递减。季节变化中生物量由大到小依次为夏季、春季、冬季、秋季,栖息密度由大到小依次为夏季、秋季、冬季、春季。多样性指数(H′)为0.9~3.0,均匀度指数(J)为0.2~0.8。结果表明东极岛种类丰富,生物量和栖息密度较高,说明东极岛地理环境较好,适宜贝类生存;物种分布均匀,生态环境稳定。     

Numerical modelling of blue mussel (Mytilus edulis) bacterial contamination

Bivalve shellfish such as oysters and mussels can concentrate human pathogens when grown in areas impacted by municipal wastewater. Under EU regulation this risk to consumers is controlled by determining the sanitary quality of bivalve shellfish production areas based on the concentration of Escherichia coli present in shellfish flesh. The authors present a modelling approach to simulate an uptake of E. coli from seawater and subsequent depuration by Mytilus edulis. The model that dynamically predicts E. coli concentration in the mussel tissue is embedded within a 3-D numerical modelling system comprising hydrodynamic, biogeochemical, shellfish ecophysiological and the newly proposed microbial modules. The microbial module has two state variables, namely, the concentrations of E. coli in water and in the mussel tissue. Novel formulations to calculate the filtration rates by mussels and the resulting uptake of bacteria are proposed; these rates are updated at every computational time step. Concentrations of E. coli in seawater are also updated accordingly taking into account the amounts ingested by mussels. The model has been applied to Bantry Bay in the south-west of Ireland. The results indicate that the model is capable of reproducing the official classification of shellfish waters in the bay based on monthly sampling at several stations. The predicted filtration rates and ratios of E. coli in water and mussels also compare well with the literature. The model thus forms a tool that may be used to assist in the classification of shellfish waters at much greater spatial and temporal detail than that offered by a field monitoring programme. Moreover, it can also aid in designing an efficient monitoring programme. The model can also be utilised to determine the contribution of individual point sources of pollution on the microbial loading in mussels and, when incorporated into an operational framework, it can provide a short-term forecasting of microbial contamination in a shellfishery. Also, the model can be easily extended to include other shellfish and pathogen species.     

The role of social norms on conservation programmes in shellfish fisheries

Ostrom (1990) has argued that in collective action problems, social factors are crucial in order to promote conservation. A survey instrument among shellfish gatherers has been used to analyse their preferences with respect to a proposed conservation management programme, assessing the effect of co-management initiatives and the impact of social norms on extraction. Results show that shellfish gatherers working in a Marine Protected Area (MPA) behave more conservatively with respect to their counterparts in terms of their current extraction patterns, promoting species conservation. With regards to social norms, expected believes about the fulfilment of the current extraction regulation in their network, allow for the acceptance of restrictions imposed by the conservation management plan without decreasing the shellfish gatherers’ utility in any significant way.     

浅海贝类养殖容量研究

贝类养殖容量概念和方法的研究开始较晚,发展较快.目前大多采用生态动力学模型的方法来研究养殖容量,它量化了贝类的生长过程,但关于贝类强烈的生理活动对环境的改造考虑不足,还不能应用于实际生产和海域使用的指导.在原有模型的基础上,导入养殖活动对自身容量反馈的模块,综合考虑影响养殖容量各个因子的权重,建立起生态效益和经济效益最优化的养殖容量模型是以后研究的重点.     

The value of marine biodiversity to the leisure and recreation industry and its application to marine spatial planning

The incorporation of the ecosystem approach into marine planning requires that all aspects of value associated with marine biodiversity are incorporated into the decision making process. An ecosystem services approach to valuing marine biodiversity is recognised as a framework by which economic, ecological and social values may be incorporated into the decision making process. There are sectors of the marine leisure and recreation industry (sub-aqua diving, sea angling and wildlife watching), which depend on the presence of natural marine resources in order to carry out their activity. Estimating the value of this direct use can provide an evidence base for the sustainable use of marine biodiversity when set against other competing economic interests in marine spatial planning. In the case study area of Lyme Bay, the marine leisure and recreation industry has been valued using both monetary and non-monetary methods. The results show that the leisure and recreation industry is dependent on the diversity of sites (many of which are currently unmanaged) and that the industry is of economic significance and an area which has recently been closed to trawling activity enables the protection of some of the most valuable sites but has limited benefits for protecting the full resource base upon which this local industry depends.     

Response of intertidal macrobenthic communities to long term human induced changes in the Eo estuary (Asturias, Spain): implications for environmental management

Long term macrobenthos data together with physical habitat parameters were analysed to investigate spatial and temporal changes at an estuary under different anthropogenic pressures, mainly increasing shellfish farming. The aim was to assess the possible impacts of these pressures on the macrobenthic communities by comparing a period before and after changes in these pressures. Benthic samples were seasonally collected in 1990 (before major anthropogenic changes), 2000 and 2005 at the same sampling stations located on three different habitats in the Eo estuary (Northern Spanish coast). Multivariate and univariate methods were used to assess spatial variability of benthic assemblages and to compare community changes over time. Data from 1990 was assumed as the reference situation to appraise the subsequent impacts. We observed a significant spatial variability of the benthic assemblages in the system as a function of habitat heterogeneity in relation to sediment composition, presence/absence and density of seagrasses, and hydrodynamic regime. Changes were detected in the community composition at all sites during this 15 year period. The extent of changes was related to initial community conditions, rather than the intensity of the pressure. The results suggest that the responses of the benthic communities to human induced perturbations occurring in the system are largely dependent on its intrinsic buffer capacity, and that these communities have been able to cope with an increasing environmental stress (organic enrichment). In conclusion, to keep shellfish farming at a sustainable level without undesirable impacts, the disturbance intensity must be kept below the system carrying capacity. This will allow natural communities to cope with pressures and thus avoid further deterioration in ecological quality.     

贻贝对麻痹性贝类毒素的蓄积代谢研究进展

麻痹性贝类毒素（paralytic shellfish toxins,PSTs）能够导致贝类、鱼类等海洋生物染毒或死亡,危害海洋生态安全及人类健康。其中,贻贝具有强蓄积性特点,在国外可作为PSTs的指示性生物。近年来,我国因食用贻贝造成多起PSTs中毒事件成为安全关注重点,因此急需弄清其风险形成机理。本文通过综述我国近海贻贝等贝类中PSTs的风险程度、贻贝对不同产毒藻来源的PSTs的蓄积作用,分析环境因子对于蓄积代谢的影响,深入挖掘贻贝蓄积代谢特异性。进而聚焦贻贝代谢阶段的表达调控过程、影响因素、转化作用及方式等。未来应侧重于摸清我国目标区域贻贝等海洋贝类中PSTs基础风险规律和变化过程,并据此建立区域性PSTs风险防控技术,提高我国贻贝中PSTs风险的主动防控能力,对于保障消费者健康和海洋生态安全具有积极意义。     

Transboundary research in fisheries

Spatial boundaries have become an indispensable part of regimes and tools for regulating fisheries, with examples including marine protected areas, regional fisheries management organizations and Exclusive Economic Zones. Yet, it is also widely acknowledged that boundaries are a social construct, which may be resisted by both fishers and fish ecology. The ensuing spatial and institutional mismatches have been shown to frustrate management efforts, exacerbating issues of non-compliance and ultimately leading to conflicts and overfishing. Interestingly, the often static and rigid nature of these boundaries has also led to a concomitant research interest in ‘transboundary’. This paradoxical situation of more boundary-setting entailing more transboundary thinking warrants a deeper understanding about boundaries and the role of transboundary research in fisheries. The aims of this review article are twofold: (1) a theoretical clarification on the meanings and uses of spatial boundaries drawing on geographical “boundary studies” literature; and (2) a construction of a typology that outlines how transboundary research is being articulated and envisioned. Together, the study reveals that transboundary scholarship in fisheries are mostly related to resources, fleets, trade and governance aspects and that dealing with the “boundary paradox” encompasses re-incorporating, re-scaling and re-imagining of boundaries. This article provides a conceptual basis for reflecting upon boundaries in world's fisheries and opens up discussions for a more nuanced boundary application that can better cope with multi-level interactions and dynamicity.     

On the large-scale variability of the circulation and heat state of the ocean and atmosphere in the North Atlantic

A conclusion about two extreme regimes existing in the large-scale circulation in the North Atlantic has been drawn based on an analysis of the inter-annual variability of the analogue to the Rossby index, as well as that of the heat and dynamic characteristics in separate areas of the north subtropical circulation. The former is defined by a high level of circulation both in the atmosphere and in the subtropical water circulation. In the current century this regime was realized mainly in the years pertaining to the middle and end of a 22-year solar activity cycle (a 22-year cycle). The relatively low level of atmospheric circulation and the slackened water mass transport are typical of the second regime. It dominated mainly during the years relevant to the beginning and second half of a 22-year solar activity cycle.Translated by Mikhail M. Trufanov.     

麻痹性贝毒毒素的应用研究进展

由于有害赤潮的发生日趋频繁，对养殖业、自然生态系统和人类健康的危害越来越大，造成的经济损失也逐渐增加，因而有害赤潮问题成为人们关注的焦点。藻毒素是有害赤潮致害的重要因子之一，而麻痹性贝毒(Paralytic Shellfish Poisoning，PSP)毒素又是藻毒素中分布最广、危害最大的一类毒素。随着科学家们对PSP毒素的来源(Steidinger，1993)、结构和作用方式(Penzotti et al.,1998)的深入研究，PSP毒素在赤潮研究、分子生物学和神经生物学基础研究、医药、军事防化等的应用也逐渐受到重视。本文作者针对这些问题进行了综合评述，以期为深入开展PSP毒素应用研究提供参考依据。     

Improving the prediction of extreme FPSO hawser tension,using another highly correlated hawser tension with a longer time record

The floating production storage and offloading unit (FPSO) is an offshore vessel that produces and stores crude oil prior to tanker transport. Robust prediction of extreme hawser tensions during the FPSO offloading operation is an important safety concern. Excessive hawser tension may occur during certain sea conditions, posing an operational risk. In this paper, the finite element method (FEM) software ANSYS AQWA has been employed to analyze vessel response due to hydrodynamic wave loads, acting on a specific FPSO vessel under actual sea conditions.In some practical situations, it would be useful to improve the accuracy of some statistical predictions based on a certain stochastic random process, given another synchronous highly correlated stochastic process that has been measured for a longer time, than the process of interest. In this paper, the issue of improving extreme value prediction has been addressed. In other words, an efficient transfer of information is necessary between two synchronous, highly correlated stochastic processes. Two such highly correlated FPSO hawser tension processes were simulated in order to test the efficiency of the proposed technique.     

Evaluating sustainability criteria for a marine protected area in Veracruz,Mexico

Marine protected areas are designed to protect natural resources within their limits. The National Park Veracruz Reef System was declared a protected area in 1992, however in the ensuing 17 years only limited measures have been taken to reduce harvesting within the area. This study was conducted as a base line to evaluate the sustainability of the park area in the present open access regime. Indicators were selected based upon sustainability attributes and criteria previously defined, patterned after a method used to evaluate sustainability in agricultural systems. To evaluate the selected indicators questionnaires were applied to the inhabitants of three fishing communities surrounding the park. Results show a precarious sustainability index for the reef system of 45.87%. We observed differences in the sustainability indices for the three communities when a classification and ordination analysis were applied. Also, applying this analysis to the indices, we found differences between social and economic criteria. The application of this kind of evaluation for the management of the area is discussed.     

贝类种群壳形态性状多态性研究进展

贝类壳形态具有丰富、复杂的多态性。壳形态作为贝类重要的数量性状是一种环境适应的进化,是不同生理功能适应其生活方式的结果,受环境和遗传因素影响,与贝类的生长、存活、代谢及繁殖等生态、生理行为密切相关。通过贝类可量可数性状建立的壳形态数值分类学方法已在贝类种群形态学比较及群体亲缘关系研究中广泛应用。本文对贝类种群壳形态性状的多态性研究进行了综述,并对壳形态分析方法在贝类种质资源评估（种群识别）及遗传育种（壳宽型/深凹型品系选育）中的应用提出展望,旨在为研究者较全面了解壳形态性状的多态性和分析方法提供参考。     

The argument for an interim arrangement

The application of an international interim regime for the ocean floor prior to the entry into force of a Law of the Sea Convention would enable timely exploitation of deep sea resources and would help towards the settlement of divergent opinions. The telecommunications organizations Intelsat and Inmarsat provide examples of how this may be successfully achieved.     

Criteria for the occurrence of wind-driven coastal upwelling associated with “Aoshio” on the southeast shore of Tokyo Bay

At the head of Tokyo Bay, coastal upwelling of oxygen-depleted bottom water, induced by northeasterly wind-driven circulation, sometimes leads to the deaths of many shellfish and other aquatic animals across large areas, resulting in substantial economic losses to coastal fisheries. One of the chemical actions associated with this dynamic process is the oxidation of hydrogen sulfide in the bottom water into a colloidal sulfur substance. When sunshine reflects off surface water containing these sulfur particles, the seawater appears milky blue. This phenomenon has been termed “Aoshio.” One of the most important issues to address concerning upwelling in relation to Aoshio is to accurately predict when it will occur as well as its area and scale. In the preliminary study described here, we propose criteria for the occurrence of wind-driven upwelling associated with Aoshio on the southeast shore of Tokyo Bay using two analytical solutions. These two solutions were derived based on some specific assumptions in the context of a two-layered fluid. Comparison with observation data suggested that the criteria were valid. The results of analyses of the sensitivity of the solutions to all of the parameters incorporated into them were also found to be in accord with our qualitative understanding of this phenomenon.     

Perspectives of the coastal and marine fisheries of the Bay of Bengal,Bangladesh

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.     

Marine systems: moving into the genomics era

The study of biological systems has been revolutionized by the use of genomic technologies. Most of the knowledge gathered over the last few years refers to terrestrial models. The study of marine systems using genomic technologies has, apart from a focus on microbial systems, been generally neglected although there are signs that this situation may be changing. This review analyses recent progress made in the field of marine genomics and identifies the broad areas in which this new technology is having the greatest impacts. These studies include comparative, functional and environmental genomics of metazoan animals. In many cases, as well as benefiting marine science, studies on marine taxa are having wide‐ranging impacts on our global understanding of genomes and genomics.     

贝类净化技术研究现状与展望

随着养殖水域环境问题日益凸显,贝类食品安全问题越来越受到重视,贝类在进入流通环节前进行净化将成为不可缺少的处理环节.本文从贝类净化工艺类型、净化用水处理技术,以及贝类净化对风味的影响等方面对当前国内外研究进展进行了总结梳理,并提出下一步贝类净化应重点解决的问题,为深入开展贝类净化相关研究提供参考.