An investigation into intersex amphipods and a possible association with aquaculture

The amphipod, Echinogammarus marinus, is common in sheltered coastal inlets, such as estuaries and sea lochs, in Scotland and exhibits increased levels of intersex in some contaminated areas. Sea lochs are commonly the location for coastal aquaculture development, and some chemicals used in fish-farming are specifically designed to target the crustacean nervous system. Therefore it was hypothesised that these chemicals may also affect neuro-endocrine pathways, causing morphological and reproductive abnormalities in non-target Crustacea. Based upon this hypothesis, Echinogammarus marinus amphipods from two different Scottish sea lochs containing salmon farms were investigated. Morphology, intersexuality, and the incidence of microsporidian parasites were recorded at sites close and at distance from fish-farms. Results suggest a higher incidence of intersexuality at sites within sea lochs, comparable to that observed in industrially contaminated sites elsewhere in Scotland. The data suggest that fish farming activity may influence the observed distributions of intersexuality within lochs. Intersex specimens were more likely to be infected by microsporidian parasites than non-intersex specimens. Normal females were found more likely to be infected by microsporidian parasites at sites associated with high intersexuality, suggesting the parasite as the probable feminiser. The cause(s) for the observed patterns of intersexuality are unclear, although suggestions relating to discharges from fish farms are discussed.     

Identification of specific malformations of sea urchin larvae for toxicity assessment: Application to marine pisciculture effluents

Standard toxicity screening tests are useful tools in the management of impacted coastal ecosystems. To our knowledge, this is the first time that the sea urchin embryo development test has been used to evaluate the potential impact of effluents from land-based aquaculture farms in coastal areas. The toxicity of effluents from 8 land-based turbot farms was determined by calculating the percentage of abnormal larvae, according to two criteria: (a) standard, considering as normal pyramid-shaped larvae with differentiated components, and (b) skeletal, a new criterion that considers detailed skeletal characteristics. The skeletal criterion appeared to be more sensitive and enabled calculation of effective concentrations EC₅, EC₁₀, EC₂₀ and EC₅₀, unlike the classical criterion. Inclusion of the skeleton criterion in the sea urchin embryo development test may be useful for categorizing the relatively low toxicity of discharges from land-based marine fish farms. Further studies are encouraged to establish any causative relationships between pollutants and specific larval deformities.     

The long and bumpy journey: Taiwan׳s aquaculture development and management

This paper presents an overview of Taiwan׳s aquaculture development and management, focusing on the transition of the industry and the current management measures that particularly address environmental effects, ecolabels and diversification into tourism and ornamental fish business. Since the late 1980s when Taiwan׳s aquaculture in its heyday was pounded by emergent environmental problems, a policy was established on enhancing governance over aquaculture, in seeking to transform it towards an environmentally, economically and socially sustainable industry. The paper shows that positive outcomes have been achieved after the policy measures have been implemented over the past two decades. However, potential challenges of ongoing environmental impacts, conflicts regarding multiple sea uses, concerns on seafood safety, lack of management of “black” farms, low market penetration of ecolabeled products and lack of participative management were identified. It argues for the need to encourage ICZM programs to solve sea use conflicts and minimize environmental impacts, reduce “black farms” to fill the management gap, enhance market shares of ecolabeled products and a transition to a more participative mode of governance.     

基于Sentinel-2影像的围海养殖信息提取

为了能够利用遥感图像快速准确地提取围海养殖矢量信息,本文选取养殖水体、堤坝及育苗室等交错分布的海参围海养殖区域作为研究区域,根据研究区域Sentinel-2遥感影像的光谱特征,选用归一化差异水体指数（Normalized Difference Water Index,NDWI）、改进归一化差异水体指数（Modified Normalized Difference Water Index,MNDWI）和增强水体指数（Enhanced Water Index,EWI）三类水体指数,分别进行提取实验,利用同时期高空间分辨率的高分二号卫星（GF-2）影像作为参考,验证不同方法的提取精度,精度评价结果表明：相较MNDWI和EWI两类水体指数,NDWI的分类精度更高,且利用NDWI提取研究区域的围海养殖信息的效果更好,所以该方法可在养殖区域的动态监测和规划管理中发挥数据支撑作用。     

Business case for mussel aquaculture in offshore wind farms in the North Sea

The European Blue Growth strategy aims to expand the new maritime sectors of aquaculture, energy, biotechnology, coastal tourism and mineral mining. Growth of these sectors will increases pressure on the seas, particularly on those areas that are densely used by traditional sectors such as fisheries and transport. This has triggered interest in developing multiuse of space and multiuse platforms at sea. This paper assesses the feasibility of offshore mussel production project in wind farms by design and ex-ante evaluation of a mussel aquaculture system in the North Sea. A system for mussel cultivation in the Dutch Borssele offshore wind farm was designed, producing both mussel seed and consumption-sized mussels with semi-submerged longlines. Based on the economic model and the risk assessment, this paper concludes that mussel aquaculture is an appealing commercial model for increased returns in offshore wind farms. The economic models shows that the internal rate of return and net present value are positive and based on the sensitivity analysis, it can be concluded that these results are robust.     

A GIS modelling framework to evaluate marine spatial planning scenarios: Co-location of offshore wind farms and aquaculture in the German EEZ

The concept of co-location of marine areas receives an increased significance in the light of sustainable development in the already heavily used offshore marine realm. Within this study, different spatial co-location scenarios for the coupling of offshore aquacultures and wind farms are evaluated in order to support efficient and sustainable marine spatial management strategies. A Geographic Information System (GIS) and multi-criteria evaluation (MCE) techniques were combined to index suitable co-sites in the German exclusive economic zone of the North Sea. The MCE was based on criteria such as temperature, salinity or oxygen. In total, 13 possible aquaculture candidates (seaweed, bivalves, fish and crustaceans) were selected for the scenario configuration. The GIS modelling framework proved to be powerful in defining potential co-location sites. The aquaculture candidate oarweed (Laminaria digitata) revealed the highest suitability scores at 10–20 m depth from April to June, followed by haddock (Melanogrammus aeglefinus) at 20–30 m depth and dulse (Palmaria palmata) and Sea belt (Saccharina latissima) at 0–10 m depth between April and June. In summary, results showed several wind farms were de facto suitable sites for aquaculture since they exhibited high suitability scores for Integrated Multi-Trophic Aquaculture (IMTA) systems combining fish species, bivalves and seaweeds. The present results illustrate how synergies may be realised between competing needs of both offshore wind energy and offshore IMTA in the German EEZ of the North Sea. This might offer guidance to stakeholders and assist decision-makers in determining the most suitable sites for pilot projects using IMTA techniques.     

陆海统筹背景下海域综合管理探析

文章分析当前海域管理面临的形势,并剖析当前存在的管理问题,提出管理的总体目标和改革意见措施,同时对当前海域使用管理法修订、新一轮国土空间规划制定、围填海管控、海岸线保护与利用管理、养殖用海管理等主要工作提出管理建议。建议包括：构建基于生态系统的海域综合管理机制,深入落实生态文明建设总要求;开展海域资源本底调查,为深化综合管理奠定基础;整合涉海规划,发挥陆海统筹作用;发挥指标调控作用,实施市场化配置;调控产业用海,充分发挥海域资源最大效益;加大整治修复力度,恢复区域生态功能;打破部门间壁垒,形成监管闭环。     

海域使用权立体分层确权及管理配套制度探讨

由于社会经济的不断发展和科技的快速进步,我国对海域空间资源的开发利用已从二维平面转向三维立体空间开发,但随之也对我国海域空间范围界定和权属管理提出了更高的要求。文章从海域立体空间分层特性出发,对我国海域使用权立体分层确权的内涵、基本原则、考虑因素进行了深入剖析,并对我国海域三维立体开发利用中面临的困境和管理配套制度的设计进行了综合探讨。研究结果表明：海域空间可以分为水面上方、水面、水体、海床和底土5个部分,海域使用权立体分层确权则是在同一海域多层次利用中,对基于特定功能用途所占用的特定海域空间开展使用权确权的过程,在海域使用权管理的过程中,必须构建和完善海域空间三维产权法律制度体系,以确保海域使用权立体分层确权的实施。     

Cypermethrin induces glutathione S-transferase activity in the shore crab,Carcinus maenas

Cypermethrin is a synthetic pyrethroid that is particularly toxic to crustacea. It is therefore applied as a chemotherapeutant in the salmonid aquaculture industry for the treatment of sea lice infestations. After use, cypermethrin is released directly into the marine environment, to be diluted by fresh seawater. The shore crab, Carcinus maenas is found in the vicinity of fish farms, and may come into contact with released cypermethrin. The detoxification enzyme, glutathione S-transferase (GST) has been implicated in cypermethrin metabolism in terrestrial arthropods, but this has not yet been demonstrated in crustacea. In this paper we investigate the response of GST activity in Carcinus to cypermethrin exposure, and also the time course of the induction process. GST activity is significantly increased in Carcinus exposed to nominal concentrations of 50 and 500 ng/l of water-borne cypermethrin. Carcinus demonstrate a significant elevation in GST activity following intra-cephalothoracic injection with 10 ng of cypermethrin. GST activity returns to basal levels after 36 h. The potential application of GST activity in Carcinus as a biomarker of cypermethrin exposure is discussed.     

GIS for land evaluation for shrimp farming in Haiphong of Vietnam

This study was conducted to identify appropriate sites for shrimp farming development in Haiphong province of Vietnam using geographical information systems (GIS). Thirteen base layers (thematic maps) were grouped into four main land use requisites for aquaculture, namely, (1) potential for pond construction (slope, land use type, soil thickness, elevation), (2) soil quality (soil type, soil texture, soil pH), (3) water availability (distance to sea, and water source), and (4) infrastructure and socio-economical status (population density, distance to roads, local markets, and hatcheries). A constraint layer was used to exclude areas from suitability maps that were not allowed to implement shrimp farming. A series of GIS models was developed to identify and prioritize the most suitable areas for shrimp farming.This study shows that the land evaluation model is useful for identifying suitable areas for shrimp farming and for allocating land for efficient income generation, effective conservation, and sustainable land management. It was estimated that about 31% (2604 ha) of the total land area (8281 ha) in Haiphong was highly suitable for shrimp farming. Since existing shrimp farms cover only 1690 ha of land in the study area, the potential for expanding shrimp farms should take into consideration further political and environmental issues.     

Escaped introduced sea bass (Dicentrarchus labrax) infected by Sphaerospora testicularis (Myxozoa) reach maturity in coastal habitats off Canary Islands

Aquaculture activities have introduced European sea bass (Dicentrarchus labrax) along the coasts of some of the Canary Islands. We present the first record of simultaneous male and female gonad maturation of escaped sea bass in the wild, indicating that this species is finding its essential fish habitat (EFH). Individuals with ripe gonads were only caught during January and February 2009, although the maturation and spawning season may last from November to February in the studied area (Tenerife island). Bass infected by Sphaerospora testicularis were found and the incidence of the parasite was checked. This represents the southernmost record of the parasite, probably introduced together with sea bass stock. The results are discussed from the point of view of risk assessment and the ecology of invasions being valuable for aquaculture management in Central North Atlantic and Mediterranean areas.     

Environmental consequence analyses of fish farm emissions related to different scales and exemplified by data from the Baltic--a review

The aim of this work is to review studies to evaluate how emissions from fish cage farms cause eutrophication effects in marine environments. The focus is on four different scales: (i) the conditions at the site of the farm, (ii) the local scale related to the coastal area where the farm is situated, (iii) the regional scale encompassing many coastal areas and (iv) the international scale including several regional coastal areas. The aim is to evaluate the role of nutrient emissions from fish farms in a general way, but all selected examples come from the Baltic Sea. An important part of this evaluation concerns the method to define the boundaries of a given coastal area. If this is done arbitrarily, one would obtain arbitrary results in the environmental consequence analysis. In this work, the boundary lines between the coast and the sea are drawn using GIS methods (geographical information systems) according to the topographical bottleneck method, which opens a way to determine many fundamental characteristics in the context of mass balance calculations. In mass balance modelling, the fluxes from the fish farm should be compared to other fluxes to, within and from coastal areas. Results collected in this study show that: (1) at the smallest scale (<1 ha), the "footprint" expressing the impact areas of fish cage farm often corresponds to the size of a "football field" (50-100 m) if the annual fish production is about 50 ton, (2) at the local scale (1 ha to 100 km2), there exists a simple load diagram (effect-load-sensitivity) to relate the environmental response and effects from a specific load from a fish cage farm. This makes it possible to obtain a first estimate of the maximum allowable fish production in a specific coastal area, (3) at the regional scale (100-10,000 km2), it is possible to create negative nutrient fluxes, i.e., use fish farming as a method to reduce the nutrient loading to the sea. The breaking point is to use more than about 1.1 g wet weight regionally caught wild fish per gram feed for the cultivated fish, and (4) at the international scale (>10,000 km2) related to the Baltic Proper, the contribution from fish farms to the overall nutrient fluxes are very small. We have also given two case-studies at the local scale where the impact of the fish farm emissions are greatest and the idea is to identify coastal areas unsuitable and suitable for fish cage farms and the reasons why. It should also be stressed that the results presented here are exemplified using emissions from fish farms, but that the underlying principles to evaluate the ecosystem effects of nutrient discharges from point source emissions are valid in a wider and more general perspective.     

ScotMap: Participatory mapping of inshore fishing activity to inform marine spatial planning in Scotland

A detailed understanding of fishing activity in Scottish waters is required to inform marine spatial planning. Larger fishing vessels are fitted with Vessel Monitoring Systems (VMS) offering spatial information on fishing activity. VMS does not cover smaller vessels (under 15 m), which fish predominantly in inshore waters where the competition for space is often greatest. To improve knowledge of the distribution of fishing activity and value of fisheries in Scotland's inshore waters, Marine Scotland conducted a participatory fisheries mapping project, known as ScotMap. The data were collected during face-to-face interviews with 1090 fishermen of Scottish registered commercial fishing vessels under 15 m in overall length and relate to fishing activity for the period 2007–2011. Interviewees were asked to identify the areas in which they fish, estimate the contribution these areas make to vessel earnings, and to provide associated information. The majority of interviews relate to creel fishing. The data collected were aggregated to provide mapped outputs of the monetary value, relative importance to fishermen and the usage of the seas around Scotland (number of fishing vessels and number of crew). ScotMap outputs provide information on the locations of inshore fishing activities and the economic importance of different sea areas at a much higher spatial resolution than was previously possible. Outputs have informed marine policy development, provide a valuable resource for marine spatial planning in Scotland and illustrate how participatory mapping can generate useful resources on the location and importance of inshore fishing areas.     

海域使用活动对海湾生态环境的压力评估——以莱州湾为例

以莱州湾为例,基于GIS和地理空间模拟框架,结合海洋生态红线区分布,建立了海域使用活动对海洋生态环境的潜在压力评估模型,空间量化评估多种海域使用活动对海洋生态环境的潜在影响。结果显示,多种海域使用活动的潜在压力总体呈近岸高于远岸、湾顶>东部>西部的分布特征;压力高值区集中于距岸10 km以内海域和5 m水深以内海域;海洋特别保护区、海洋自然保护区及重要河口生态系统等类型的海洋生态红线区受到开放式养殖、围海养殖、盐业用海活动的压力较大,需要对其进行重点监控。研究揭示了莱州湾海域使用活动对海洋生态环境潜在压力的空间分布格局,为海洋生态红线落地实施和海域使用管理提供决策依据。     

An evaluation of the relative risks of infectious salmon anaemia transmission associated with different salmon harvesting methods in Scotland

In aquaculture, harvesting presents an unavoidable risk of disease transmission. The spread of the disease infectious salmon anaemia appears to have been associated with harvesting in both Scotland and Norway. An assessment is made of the relative risks of disease transmission associated with various different means of harvesting farmed salmon based on the assumption that best practice is followed for each harvest method. The assessment is qualitative, quantitative data being absent for most of the processes involved. Slaughter on the farm risks the spread of infection to adjacent farms, whereas, infection at a processing plant may be rebroadcast by well-boats. The risks associated with transporting live fish in cages and of storing live fish near centralised processing plants are discussed. Provided the vessel does not release contaminated water in the vicinity of salmon farms, transport of live fish directly to the processing plant for immediate slaughter by sea may be the safest means of collecting harvest.     

基于地租理论的养殖用海海域使用金定价机制探讨

为进一步推动我国海域有偿使用制度的顺利实施、促进海域资源市场化的有效运作以及提升海洋资源的开发利用效率,文章以养殖用海海域为例,概述地租理论的发展历程、我国养殖用海海域使用金征收现状和海水质量状况以及基于地租视角的养殖用海海域使用金制定标准。研究结果表明:我国养殖用海海域使用金的制定存在年代久远、现势性较差以及不同地区差别较大等问题;为在经济层面上实现海域所有权,国家应向海域使用者征收绝对海租;由于海水质量和地理位置等因素直接影响养殖用海等海域开发利用活动的整体效果和经济利益,也应根据不同资源禀赋收取级差海租。因此,从地租角度考察养殖用海海域使用金的制定,应是绝对地租和级差地租的综合体现。     

江苏近海紫菜养殖区的空间扩张模式研究

为精准实施海域使用现状的动态监测与有效管理,开展了江苏近海紫菜养殖区空间扩张模式研究.选取1990年、2000年、2013年和2018年四个时相的Landsat遥感影像为数据源,采用面向对象分类方法提取江苏近海紫菜养殖区的空间分布信息,分别计算1990年、2000年、2013年和2018年江苏近海紫菜区养殖面积并分析其...     

区域养殖用海集约利用评价方法及应用

对于养殖用海集约利用评价,目前国内相关研究还非常缺乏。文章借鉴现阶段耕地集约利用的研究方法,结合养殖用海特征,对养殖用海集约利用内涵进行了界定,从海域利用程度、海域投入强度、海域利用效益、海域利用可持续性4个层面遴选10项指标建立了养殖用海集约利用评价指标体系,并以2016年为数据年份,选取我国9个沿海省、市、自治区进行区域养殖用海集约利用评价分析。结果显示,我国养殖用海集约利用整体处于较低水平,暂无高度集约利用省份,福建、广西、天津、山东等地处于相对集约状态,并从各准则维度进行了细化分析,提出优化利用方向。     

海域使用权立体分层设立若干问题探究

海域使用权立体分层设权是国家鼓励探索的一种用海新模式,海域空间的立体化开发利用已成必然趋势,但海域管理领域真正涉及海域使用权立体分层管理机制的系统性研究几乎没有。研究表明：国家是海域使用权立体分层设立的唯一主体;同一宗海区块空间已设定水体用海使用权可开发利用的海域空间边际外部分为客体范围;无偿划拨和有偿出让是两种常见设立方式;迭代升级行政审批程序应增加海域立体空间规划、创新空间管理体系,同时要考虑线性用海动态性;从登记客体、观测技术、登记制度、登记方法和登记内容5个维度改革创新权属登记模式;可通过研制海域使用权立体分层开发规划,赋予已设定海域使用权人优先权,支持相邻海域使用权人设立海域役权等方式协调与已设定海域使用权人权益。     

Assessment of aquaculture impact on mangroves of Mahanadi delta (Orissa), East coast of India using remote sensing and GIS

Aquaculture is one of the fastest growing food industries. However, the rapid growth of aquaculture worldwide has resulted in growing concerns about its impact on important ecosystems. The expansion of aquaculture farms in the coastal areas has led to conversion of mangroves, more rapidly. To assess the impact of aquaculture on mangroves, the present study has been undertaken in Mahanadi delta of Orissa, East coast of India which is famous for its distinctive mangrove ecosystem. It has undergone tremendous changes due to the development of aquaculture and agriculture activities during last two decades. For this, satellite data of different time periods (Landsat MSS of 1973, Landsat TM of 1990 and IRS P6 LISS III of 2006) were used. It was found that the delta was occupied by dense mangrove (12.6%), open mangrove (3.3%), aquaculture (12.9%) and agriculture (30.9%) in 2006. A loss of 2606 ha mangrove area and an increase of 3657 ha aquaculture area was observed from 1973 to 2006 clearly depicts the augment of aquaculture industry. It is suggested that, regular monitoring of the mangroves and effective implementation of coastal management laws be strictly undertaken to prevent the further loss mangroves in Mahanadi delta.