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1.
Henrice M. Jansen Sander Van Den Burg Bas Bolman Robbert G. Jak Pauline Kamermans Marnix Poelman Marian Stuiver 《Aquaculture International》2016,24(3):735-756
Following the Blue Growth ambition of the European Commission, the interest in the potential of offshore is growing. This paper aimed to contribute to the discussion on the feasibility of offshore aquaculture development and its potential for multi-use with other maritime activities. A review of national and international projects forms the basis of the paper, where the Dutch North Sea is used as a case-study area. Analysis of technical, economic and ecological boundaries indicated that the potential of fish culture is limited, that seaweed cultivation is likely to gain potential when challenges related to processing will be overcome and that mussel culture has the highest potential in the near future. The North Sea is an area where many stakeholders claim space, which might set boundaries to the number of sites available for mussel culture. Competing claims are a potential source of conflict but may also lead to mutual benefits when smart combinations are sought, e.g. with wind parks, fisheries and nature conservation; especially, the possibility of combining mussel culture in or around wind parks is worthwhile to be further explored. A spatial distribution model adapted for the Dutch North Sea conditions demonstrated that offshore mussel production in wind farms can be profitable. Yet, the commercial interest for offshore development of mussel culture is still limited. Actions required to stimulate further development of the offshore mussel industry are presented for the government, the private sector, research institutes and civil society organizations. 相似文献
2.
JOACHIM MAES KARIN E. LIMBURG ANTON VAN DE PUTTE FRANS OLLEVIER 《Fisheries Oceanography》2005,14(1):17-31
Herring (Clupea harengus) enter and remain within North Sea estuaries during well‐defined periods of their early life history. The costs and benefits of the migrations between offshore spawning grounds and upper, low‐salinity zones of estuarine nurseries are identified using a dynamic state‐variable model, in which the fitness of an individual is maximized by selecting the most profitable habitat. Spatio‐temporal gradients in temperature, turbidity, food availability and predation risk simulate the environment. We modeled predation as a function of temperature, the optical properties of the ambient water, the time allocation of feeding and the abundance of whiting (Merlangius merlangus). Growth and metabolic costs were assessed using a bioenergetic model. Model runs using real input data for the Scheldt estuary (Belgium, The Netherlands) and the southern North Sea show that estuarine residence results in fitter individuals through a considerable increase in survival probability of age‐0 fish. Young herring pay for their migration into safer estuarine water by foregoing growth opportunities at sea. We suggest that temperature and, in particular, the time lag between estuarine and seawater temperatures, acts as a basic cue for herring to navigate in the heterogeneous space between the offshore spawning grounds at sea and the oligohaline nursery zone in estuaries. 相似文献
3.
DoHoon Kim 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):103-117
The economic performance of the current inshore rock bream aquaculture industry conducted in Yeosu, Korea was compared with a pilot commercial scale offshore aquaculture farm in Jeju, Korea. Data was collected from 12 inshore farms and two production cycles of the offshore farm for use in Monte Carlo simulations run over a ten year time horizon. Net present value was compared for the inshore farms and two survival rate scenarios for the offshore farm. The offshore farm is expected to have a higher survival rate if it can withstand tsunamis and avoid pollution, disease and red tide impacts that are prevalent inshore. When the offshore farm was modeled with its observed higher survival rate, its average net present value ($1,016,483) significantly outperformed the inshore farms average net present value ($182,153). In the second scenario, the offshore farm survival rate was lowered based on performance data from the inshore farms. Not surprisingly, given the higher investment costs, the offshore farm performed poorly in terms of average net present value ($-137,142) compared to the inshore farms when it no longer had the advantage of high survival rates. 相似文献
4.
实验以2005—2014年我国浙江省和江苏省沿海的养殖海藻为研究对象,利用替代成本法和机会成本法对海藻养殖直接与间接生态系统服务价值进行评价。研究结果表明,养殖海藻场产生的直接生态服务价值主要包含三项:海藻固碳价值、海水富营养化调节价值和重金属移除价值;间接生态服务价值包括避免森林转化价值、避免淡水资源、减少化肥和农药使用价值。2014年,浙江省海藻养殖的三项直接生态服务价值分别达到了40.96万元、196.55万元、60.71万元,江苏省则分别为25.83万元、123.98万元、38.29万元;浙江省海藻养殖的四项间接生态服务价值则分别达到46 487.04万元、1 160.78万元、308.52万元、1 176.71万元,江苏省为29 321.52万元、732.15万元、194.60万元、742.21万元。海藻养殖的生态服务价值远大于海藻的直接经济价值。我国海岸带面积广阔,海藻养殖潜力巨大。发展海藻养殖不仅可以部分缓解全球粮食危机,而且对减少碳排放、减少营养盐污染和应对全球变化也具有积极意义。 相似文献
5.
Around the world there is strong interest in the aquaculture of spiny lobsters (family Palinuridae). However, there is little published information about the economic feasibility of spiny lobster aquaculture. For more than 20 yr there has been experimental grow out of the spiny lobster Jasus edwardsii in New Zealand in land-based systems using seed animals (puerulus) taken from the wild. These studies provide sufficient information on growth, mortality, food conversion, handling and capital costs to enable an assessment of the economic feasibility of the commercial culture of spiny lobsters in temperate waters. This assessment suggests that profitable spiny lobster aquaculture will rely on greatly reducing the infrastructure and operating costs of land-based farming operations, as well as lowering feed and labor costs. Financial simulations suggest that increasing productivity through faster growth rates and lowered culture mortalities will only have a minor effect on profitability unless infrastructure and operating costs can be reduced significantly. Seacage culture or sea ranching of spiny lobsters may offer a means of avoiding high infrastructure costs associated with land-based farming operations. The development of a cost-effective artificial feed would also appear to be a priority for improving the economic outlook for culturing spiny lobsters. The results of this study are relevant to the economics of spiny lobster culture developments in other temperate regions of the world. 相似文献
6.
Sununtar Setboonsarng Peter Edwards 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):151-162
Abstract This paper uses a linear programming model to examine the economic viability of four fish production strategies in the context of rainfed farming systems in the north‐eastern region of Thailand. The four systems are rice bran feeding system, pond fertilization using buffalo manure, fish production recommendations developed by the Asian Institute of Technology (AIT) Recommendations and an integrated duck/fish production system. These systems have been introduced into North‐eastern Thailand where the main obstacles to fish production are the lack of indigenous knowledge offish culture and a shortage of water. While technical feasibility studies are needed to evaluate the practical viability of aquaculture technologies, economic assessment is required to assess their commercial viability. The objective of this paper is to examine whether or not these fish production systems can contribute to, and integrate with, the prevailing farm system in the North‐east of Thailand. The linear programming model is used to determine the optimum on farm product mix that maximizes net returns under each of the four production systems. Among different resources, labour requirement in the fish‐stocking month appeared to be the first binding resource, while capital requirement was not a constraint for an average farming household of the region. A sensitivity analysis is presented to show how each of the fish production systems operates with different levels of pond size, labour and capital availability. The results of the study show that these aquaculture systems are economically attractive and can contribute significantly to the livelihood of the small‐scale farmers of North‐east Thailand. 相似文献
7.
8.
This study aimed to analyze the economic effect of the red sea bream Pagrus major offshore aquaculture production system in Korea. Based on the data collected, revenue and expenses throughout the culture period were calculated, and the net present value and internal rate of return of the ten-year cash flow and cash outflow were estimated in order to determine the economic validity of red sea bream offshore aquaculture production. Results showed that the red sea bream offshore aquaculture production system had high profitability based on the current production and market conditions. This is because of its relatively high survival rate, relatively low feed conversion ratio, and good market price level. However, sensitivity analyses of the main variables indicated that the profitability of red sea bream offshore aquaculture is highly vulnerable to production conditions and market condition changes. 相似文献
9.
Georgia M. Ward Joseph P. Faisan Jr Elizabeth J. Cottier-Cook Claire Gachon Anicia Q. Hurtado Phaik E. Lim Ivy Matoju Flower E. Msuya David Bass Juliet Brodie 《Journal of the World Aquaculture Society》2020,51(4):815-828
Seaweeds have been used as a food for centuries in Asia and are increasingly exploited as a source for dietary supplements, animal feed, chemicals, and biofuels. In recent years, there has been an increase in the prevalence of diseases and pests in these aquaculture crops, with a subsequent reduction in their quantity and commercial value. In this article, we review diseases that have been reported in the scientific literature for species of red and brown seaweeds. We have focused on the major seaweed crops grown in Asia, where much of this production is centered. We also provide information on disease management and biosecurity and some observations on future directions. 相似文献
10.
Pham Thi Anh Ngoc Miranda P. M. Meuwissen Le Cong Tru Roel H. Bosma Johan Verreth Alfons Oude Lansink 《Aquaculture Economics & Management (Blackwell Science)》2016,20(2):185-200
This study aims to analyze the economic feasibility of recirculating aquaculture systems (RAS) in pangasius farming in Vietnam. The study uses a capital budgeting approach and accounts for uncertainty in key parameters. Stochastic simulation is used to simulate the economic performance of medium and large farms operating with a traditional system or RAS. Data are obtained through structured surveys and a workshop in the Mekong River Delta. Results show that for large farms, net present value increases from an average of 589,000 USD/ha to 916,000 USD/ha after implementing RAS. Overall, the probability that RAS is a profitable investment is found to be 99% for both farm sizes. With RAS, the crucial parameters determining profitability are price, yield, costs of fingerling, feed, and initial investment. Findings on the robustness of the economic performance of RAS are useful to support public and private decision making towards increasing the sustainability of pangasius production. 相似文献
11.
An economic analysis of tray cultured oysters in Dongonab Bay, Red Sea was conducted based on production costs collected by the Red Sea Fisheries Research Centre. The analysis showed that oflbottom oyster farming was economically attractive at a price around 1.5 Sudanese pounds (US $0.75) per kilogram of shell and discount rates of 40% or less. 相似文献
12.
Diego Valderrama Junning Cai Nathanael Hishamunda Neil Ridler Iain C. Neish Anicia Q. Hurtado 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):251-277
The farming of the red seaweed Kappaphycus alvarezii and related species as raw material for the hydrocolloid carrageenan rapidly spread from the Philippines in the late 1960s to Indonesia, Tanzania, and other tropical countries around the world. Although numerous studies have documented positive socioeconomic impacts for seaweed farming, factors such as diseases and distance to export markets have led to an uneven development of the industry. Using standard budgeting techniques, this study adapted production and market data from a FAO-led global review of seaweed farming to develop comparative enterprise budgets for eight farming systems in six countries (Indonesia, the Philippines, Tanzania, India, Solomon Islands, and Mexico). Although the basic technology package is the same across countries, the study revealed large differences in the economic performance of systems due to wide variations in farm prices and the scale of operations. Although seaweed farming is a suitable activity for small-scale producers, a minimum of 2,000 m of cultures lines are still necessary to ensure adequate economic returns. Greater farming plots may be needed if farm prices are well below the average farm prices paid in Indonesia and the Philippines. Policy recommendations are made to improve the economic potential of underperforming systems. 相似文献
13.
Hasmadi Mamat Jahurul Md. Haque Akanda Mohamad Khairi Zainol Yu Ai Ling 《Journal Of Aquatic Food Product Technology》2018,27(5):635-642
Seaweed has a great potential to be used as an important ingredient in food processing, as it contains a significant content of soluble polysaccharides and has a potential function as a dietary fiber. In this study, seaweed powder (Kappaphycus alvarezii) was incorporated (2–10%) with wheat flour for the production of muffins. The effect of seaweed composite flour on the quality of muffins was investigated using various techniques, such as texture profile and proximate analyses, as well as sensory evaluation. Modification of the muffin formulation to include seaweed powder improved the composition of ash, crude fiber, and moisture content, while the protein and carbohydrate levels decreased, compared to the control sample. An increase in the seaweed component reduced the muffin height, volume, and specific volume. According to the experimental texture profile analysis data, the seaweed affected the textural characteristics of the muffins, increasing the hardness and decreasing the springiness. Sensory evaluation revealed that seaweed powder could be used in the muffin formulation up to 6%, without significantly impacting the color, aroma, and taste attributes relative to the control sample. For overall acceptability, however, the panelists preferred muffins without seaweed powder. 相似文献
14.
Thales Ramon Q. de Bezerra Ernesto C. Domingues Luiz Flávio A. Maia Filho Artur N. Rombenso Santiago Hamilton Ronaldo O. Cavalli 《Aquaculture International》2016,24(2):609-622
Economic feasibility studies regarding aquaculture systems are relatively scarce, but they are important to potential investors and for the allocation of resources for research and technological development. This study evaluated the economic viability of cobia cage culture from the actual investment and operational costs of a large-scale operation off Recife, northeastern Brazil (industrial system; IS), and a family-run farm located in a near-shore area of Rio de Janeiro (familiar system; FS). The IS had twenty-four 1607 m3 floating cages deployed at a depth of 24 m, while the FS had six 75 m3 wooden cages installed in a sheltered 6- to 7-m-deep area. Analyses of profitability (gross revenue, operational profit, cost price and break-even production) and investment (net present value—NPV; and payback time) were performed. An analysis of sensitivity was also carried out. The IS required an initial investment of approximately US$ 1.5 million dollars and was more sensitive to FCR, selling price and productivity fluctuations than the FS. The FS required a relatively small initial investment (US$ 16,000 dollars), which makes it more flexible to variations in production parameters and market fluctuations. The NPV was positive for both systems, and the payback times were estimated to be 3.88 years for the IS and 2.07 years for the FS. Therefore, given the assumptions of this study, cage culture of cobia in Brazil may be considered economically feasible in offshore production systems and in near-shore, FSs. Governmental support through decreased import taxes is recommended as a way to accelerate the early development of the cage culture of marine fish in Brazil. 相似文献
15.
为掌握黄海北部辽宁近岸海域鳀(Engraulis japonicus)产卵场的分布特征及其关键环境因子,基于2021年4—12月开展的产卵场综合调查获取的鳀样品及其鱼卵密度数据,运用Garrison重心分布法阐释鳀产卵洄游分布特征及其主产卵期;通过基于Tweedie分布的广义可加模型(generalized additive model, GAM)的构建,分析主产卵期内鳀卵密度与同步获取的海水表层温度(SST)、海水表层盐度(SSS)、海水表层叶绿素浓度(Chla)、浮游动物丰度(Fd)、浮游植物丰度(Fz)和深度(Depth)等6个环境因子,以及时间(月份,Month)和空间(经纬度、Lon和Lat)因子之间关系,并识别主控因子。结果显示,海域内鳀产卵期较长,由4月持续至11月,5—8月为主产卵期,其中,5—6月为产卵盛期。鳀产卵场规模和位置时空变化明显,时空因子与鳀卵密度分布呈密切非线性相关(累积偏差解释率为48.1%),(SST, SSS) (18.7%)和Depth (5%)次之。鳀产卵期适温范围较广,产卵场分布表现出高温高盐(低温低盐)增效作用和高温低盐限制作用。产卵初期(4月),鳀产卵场规模和鱼卵密度均较低,产卵重心位于海洋岛东南侧深水区;盛期(5月底—6月初)在SST主导下,鳀产卵场规模和鱼卵密度均至年内最高值,核心产卵场位于石城岛–庄河河口一带海域;此后,随着辽南沿岸水系盐度的下降,高温低盐的抑制作用使SSS因素主导产卵鱼群避开沿岸海域,鳀产卵场迁移至外海深水区,7月后位于30~50 m等深线之间;9—10月鳀繁殖活动基本结束,10月鳀卵仅零星分布于调查海域,直至12月未有鳀卵采获。研究可为黄海北部辽宁近岸海域鳀产卵场研究及鳀资源合理开发利用提供参考依据。 相似文献
16.
Carbon and nitrogen stable isotope ratios in the muscle of Dall’s porpoises were measured. Samples were collected from the catches of the hand harpoon fishery, incidental catches of drift net, and scientific research on the use of drift nets. Samples were from the North Pacific, Sea of Japan, Sea of Okhotsk, and Bering Sea. Although no variation in δ15N was observed, δ13C was significantly different between population groups near Japan and the oceanic North Pacific and Bering Sea. The difference may be due not only to local variation in prey species, but also to an overall difference in carbon stable isotope ratios that originate from coastal benthic or oceanic pelagic‐based food webs. We differentiated Dall’s porpoise population groups from both areas using carbon stable isotope ratios with an error rate of <5%. Although further study is needed, our results suggest that carbon stable isotope ratios could possibly be an indicator of whether a Dall’s porpoise belongs to a coastal benthic or oceanic pelagic food web. 相似文献
17.
B. BRAATEN 《Aquaculture Research》1994,25(1):129-129
Abstract. The concept of farming Atlantic salmon, Salmo salar L., beyond smolt stage in sea water started in Norway and Scotland in 1967–1968, using natural enclosures or sea water ponds. Cage culture has since 1969 developed to be the dominating method. Atlantic salmon is cultivated in more than nine countries with a production of 235400t in 1990. Incubation of eggs, hatching, first feeding and smolt production have to a large degree been standardized. Various types of incubator systems and holding units are briefly presented and discussed. There has recently been a trend to move ongrowing cage farms from inshore and sheltered waters to more open and offshore locations. The various types of cages and supplemental equipment for the two options are compared and evaluated. The offshore trend is a more expensive and difficult technology than existing inshore farming methods. Sea enclosures and net enclosures are less attractive. There is new interest in pump ashore systems. Large land-based farms have been built in six countries with varying success. The amounts of water required are enormous and constructions costs are high, but running costs are comparable to cage culture. Great improvements have taken place for both smolt farms and pump ashore farms in treatment of water, use of heat exchangers, filtration of water, disinfection, aeration, oxygenation, photoperiod and light control, automatic feeding, internal transport, handling of fish and surveillance and control systems for fish and water. The problems and prospects of farming are discussed in relation to new and old technology. 相似文献
18.
We present a new, intuitive approach for the representation of fisheries catches within profiles perpendicular to coast of the Exclusive Economic Zones (EEZ) of countries, or of Large Marine Ecosystems (LME). These ‘catch transects’ show where catch is extracted in the water column and near the sea bottom on plots of log‐bathymetry versus log‐distance offshore and thus allow for representation of the catch density of pelagic and benthic fisheries. Hence, they also allow direct visual comparison of the intensity of fishing through time and space. The California Current, North Sea and the South China Sea LMEs and the EEZs of Australia, Canada, Chile, China, India and Thailand are presented as examples, revealing the general intensification and extension of fishing offshore and into the depths over the decades from the 1950s. Catch transects reveal how these trends have accelerated in some areas, but surprisingly have reversed themselves in some others. It is proposed that these catch transects will be particularly useful for communicating the results of large‐scale fisheries studies to a wide spectrum of groups ranging from the fishing industry to the general public. 相似文献
19.
海藻中无机砷超标问题研究 总被引：8，自引：0，他引：8
我国是海藻生产大国,藻类是人们喜爱的健康食品.但新的海藻制品卫生标准和食品中无机砷检测方法标准实施后,依照该标准检测发现海藻中的无机砷超标问题十分严重.为探讨其原因,调查了国内外的紫菜、海带等产品总砷、无机砷含量,分析了不同收割期的鲜紫菜及其加工制品以及养殖区域水质中无机砷变化情况.结果发现:按新的卫生标准及其检验方法检测,海藻中无机砷普遍超标;紫菜中的无机砷与养殖区水质中无机砷含量的变化并非成线性关系;GB/T 5009.11中的两种测定方法对海藻中无机砷的检测结果有明显差异,不适用于海藻中的无机砷检测. 相似文献
20.
Abstract. In aquaculture experiments of only a few months'duration, fish can approach their asymptotic size and growth rates may change greatly. One objective of aquaculture is to obtain a maximum economic return, and a growth model is needed to relate rate of growth to food consumption and other costs to find the optimum duration of growth cycles. Von Bertalanffy's equation is an asymptotic growth model which can be used for this purpose. A variable growth rate model was developed to describe fish growth oscillations observed in aquaculture experiments. This growth model provides improved estimates of von Bertalanffy's equation in aquaculture and can be used for an efficient evaluation of fish production during production cycles. 相似文献