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Marc Metian Max Troell Villy Christensen Jeroen Steenbeek Simon Pouil 《Reviews in Aquaculture》2020,12(2):1090-1100
Aquaculture is the world's most diverse farming practice in terms of number of species, farming methods and environments used. While various organizations and institutions have promoted species diversification, overall species diversity within the aquaculture industry is likely not promoted nor sufficiently well quantified. Using the most extensive dataset available (FAO‐statistics) and an approach based on the Shannon Diversity index, this paper provides a method for quantifying and mapping global aquaculture species diversity. Although preliminary analyses showed that a large part of the species forming production is still qualified as undetermined species (i.e. ‘not elsewhere included’); results indicate that usually high species diversity for a country is associated with a higher production but there are considerable differences between countries. Nine of the top 10 countries ranked highest by Shannon Diversity index in 2017 are from Asia with China producing the most diverse collection of species. Since species diversity is not the only level of diversity in production, other types of diversity are also briefly discussed. Diversifying aquatic farmed species can be of importance for long‐term performance and viability of the sector with respect to sustaining food production under (sometimes abrupt) changing conditions. This can be true both at the global and regional level. In contrast, selection and focus on only a limited number of species can lead to rapid improvements in terms of production (towards sustainability or not) and profitability. Therefore, benefits and shortcomings of diversity are discussed from both economical and social‐ecological perspectives that concurrently are shaping the expanding aquaculture industry. 相似文献
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All‐male monosex culture of Macrobrachium rosenbergii (De Man) has emerged as a popular practice in India, especially in the state of Andhra Pradesh. A study was conducted to compare the economics of all‐male, mixed and all‐female culture in 15 adjacent, rectangular ponds of 4000 m2 each by stocking juveniles previously reared in a nursery for 60 days. The experiment was conducted using a completely randomized design with three treatments; T1 (all male), T2 (mixed) and T3 (all female), and five replicates for a period of 5 months after the nursery phase. Statistical analysis showed highly significant (P<0.01) differences among the three types of culture. The cost of production was estimated and the economic feasibility of the culture methods was evaluated by cost‐return and partial budgeting analysis. The average weight, productivity and specific growth rate were the highest for all male culture, being 80.92±2.41 g, 1532 kg ha?1 and 1.97±0.02 respectively. All‐female culture registered significantly higher survival (89.16±0.77%) and the best apparent feed conversion ratio of 1.26±0.02. The economic analysis revealed that all‐male monosex culture of M. rosenbergii was 63.13% and 60.20% more profitable than mixed and all‐female cultures respectively. 相似文献
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Pedro E. Saucedo Douglas McLaurin César Lodeiros Luis Freites Luis León Jorge I. Cáceres-Puig Marcos C. P. Albuquerque Paul C. Southgate Héctor Acosta-Salmon 《Reviews in Aquaculture》2023,15(1):242-260
Globally, pearl culture is a profitable sector generating significant export incomes for producer countries, as well as livelihood opportunities for local communities. Latin America has a long history as a pearl producer from extensive fisheries that date back to the 15th century. The presence of pearl oyster beds on the Pacific and Caribbean coasts of many Latin American countries was a major incentive for colonisation of the region and subsequent social and economic development of areas in the Gulf of California and the Caribbean. This review presents the historic background of the pearl fishery in this region since the arrival of the Spanish in the 16th century, describes the current status of pearl culture in Latin America, and outlines future opportunities for sector development. Information on the current status of pearl culture in Latin American countries is divided between two major categories: commercial and pilot-scale. Commercial pearl production currently occurs only in Mexico and production updates are provided for bead-nucleated, half pearls (mabé) and non-nucleated (keshi) pearls from the two pearl farms operating in the Gulf of California. The second category comprises countries whose pearling activities were relevant in the past (Venezuela, Panama) and others that are emerging, but still maintain pilot-scale production of mabé pearls using Pteria sterna (Ecuador, Peru), Pinctada mazatlanica (Panama) and Pteria hirundo (Brazil). Finally, this review discusses future prospects for pearl culture in Latin America, analysing technology gaps and challenges to be addressed if the cultured pearl sector is to achieve its full potential in this region. 相似文献
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以马氏珠母贝(Pinctada martensii)速长系F2为材料,分析了贝龄对植核贝生长、成活率和育珠性状影响。实验设2.0龄贝植核组(A)、2.0龄贝对照组(B),1.5龄贝植核组(C)和1.5龄贝对照组(D),按照常规技术进行插核手术与海区养殖,育珠期为450 d。在插核后第15、30、60、180、270和450天,比较各组的平均体质量和成活率差异;在插核后270 d和450 d,比较A和C组留核率、珍珠层厚度、优质珠率和珍珠产量的差异。结果表明,在插核后第15、30、60、180和270和450天,4个组的平均体质量和成活率均存在显著性差异(P<0.05),C和D组的成活率显著大于A和B组(P<0.05),C和D组的体质量日增长率显著大于A和B组(P<0.05)。在插核后第270天,A和C组的留核率、珍珠层厚度和珍珠产量均存在显著性差异(P<0.05),A和C组间优质珠率差异不显著(P>0.05);在插核后第450天,C组留核率、珍珠厚度、优质珠率和珍珠产量均显著大于A组(P<0.05)。结论认为,利用低龄贝进行插核育珠明显提高植核贝的留核率、成活率和珍珠层厚度,从而能够提高珍珠质量。本研究旨在为合理设计马氏珠母贝的养殖模式提供科学依据。 相似文献
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The promotion of Blue Growth in aquaculture requires an understanding of the economic drivers influencing the sector at farm level, but the collection of reliable and comparable data at this level is time‐consuming and expensive. This study suggests an alternative strategy for qualitative sampling of freshwater trout farms in Germany, Denmark and Turkey, using a combination of existing data, group discussions and interviews with trout farmers, consultants and researchers. Nine ‘typical’ trout farming models are described, focusing on profitability, productivity and energy efficiency and allowing in‐depth comparative economic analyses of different production systems at farm level, across regions. Our results show that the majority of the farms investigated have been profitable. Turkish farms benefit from competitive advantages due to low wages, low capital investment and favourable climate conditions. Large German farms profit from local market prices and advanced farm management. Danish farms using recirculating techniques remain competitive thanks to enhanced productivity and economy of scale. However, small traditional farms in Germany and Denmark may struggle to stay competitive in the long term. Organic farms in both countries face challenges of high feed costs and comparatively low productivity with mixed success. Using edible protein energy return on investment (epEROI) as an indicator of ecological sustainability, all surveyed farms compared very favourably with the terrestrial systems of animal meat production were investigated so far. 相似文献
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Marisol Beltran‐Gutierrez Sebastian CA Ferse Andreas Kunzmann Selina M Stead Flower E Msuya Thomas S Hoffmeister Matthew J Slater 《Aquaculture Research》2016,47(5):1549-1559
Commercially valuable sea cucumbers are potential co‐culture species in tropical lagoon environments, where they may be integrated into established aquaculture areas used for seaweed farming. In the current study, wild‐caught juvenile sea cucumbers, Holothuria scabra, and red seaweed Kappaphycus striatum were co‐cultured on Zanzibar, United Republic of Tanzania. Sea cucumbers (97 g ± 31 SD, n = 52) were cultured in mesh enclosures at initial cage stocking densities of 124 ± 21 SD and 218 ± 16 SD g m?2 under seaweed culture lines. Over 83 days, individual growth rate (1.6 g d?1 ± 0.2 SD) of sea cucumbers at low stocking density was significantly higher (χ2 = 8.292, d.f. = 1, P = 0.004) than at high‐stocking density (0.9 g d?1 ± 0.1 SD). Seaweed individual growth rates [6.27 (±0.3 SE) g d?1] were highest in co‐culture with sea cucumber at low density but did not differ significantly from high sea cucumber density or seaweed monoculture treatments (χ2 = 3.0885, d.f. = 2, P = 0.2135). Seaweed growth varied significantly (χ2 = 35.6, d.f. = 2, P < 0.0001) with sampling period, with the final sampling period resulting in the highest growth rate. Growth performance for seaweed and sea cucumbers (χ2 = 3.089, d.f. = 2, P = 0.21 and χ2 = 0.08, d.f. = 1, P = 0.777 respectively), did not differ significantly between monoculture and co‐culture treatments, yet growth in co‐culture was comparable with that reported for existing commercial monoculture. Results indicate H. scabra is a highly viable candidate species for lagoon co‐culture with seaweed. Co‐culture offers a more efficient use of limited coastal space over monoculture and is recommended as a potential coastal livelihood option for lagoon farmers in tropical regions. 相似文献
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幼蚌实行强化培育,植珠工艺改为“三小”,调整嫁接季节和适时调节育珠蚌的吊养深度,可使优质珍珠培育周期缩短为二夏一冬,优质珍珠比率由原来的8％上升到20％以上。 相似文献
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The winged pearl oyster, Pteria penguin, is cultured primarily to produce half‐pearls (mabé). The mabé quality is influenced by culture techniques, but there is limited information in this field. P. penguin with mean (±SE) dorso‐ventral height of 250 ± 6.5 mm were used to investigate the influence of culture period and nucleus position on mabé quality. Oysters were relaxed using 1‐propylene phenoxetol, and five nuclei were glued at different positions to the inner surfaces of the oyster shells; three on the more concave left valve and two on the right valve. Nucleated oysters were then cultured for 10 months under commercial pearl farming conditions at Savusavu in Fiji. Nacre deposited at the base and top of the nuclei was measured monthly, from the 6th to the 10th months of culture and the different qualities of mabé produced at different positions were scrutinized. Nacre thicknesses at the base and top of the resulting mabé were significantly different at different months (P < 0.05) and the rate of nacre deposition was highest during the warmer months. The different positions of nuclei on the valve greatly affected the quality of mabé formed. After a 10‐month culture period, around 1 mm of nacre covered the nuclei although the best quality mabé were obtained after 9 months. 相似文献
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黑蝶贝养殖现状与前景初步分析 总被引：1，自引：0，他引：1
黑蝶贝是目前唯一能批量生产黑珍珠的珍珠贝类。20世纪70年代以来,国内开始进行黑蝶贝的研究和培育,在人工育苗、苗种中间培育、插核术前处理、关键插核技术及术后休养等方面取得了一定的研究进展,但目前还没有达到规模化生产程度。在养殖及珍珠培育过程中遇到的主要问题是:苗种培育阶段暴发的外套膜流行病;海洋环境恶化导致的高死亡率;插核后死亡率、脱核率高,造成存珠率不高等。针对黑蝶贝繁育、培育、插核等技术的研究进展及养殖现状与问题进行述评,为黑蝶贝健康养殖的进一步研究及黑珍珠的规模化生产提供参考。 相似文献
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G. Syda Rao R. Narayana Kumar 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):130-144
Land-based marine pearl culture is a novel technological concept suitable for all three important species of pearl oysters. Advantages include lack of fouling and avoidance of boring and predation. An economic evaluation of onshore marine pearl culture production was conducted to provide basic information about the practice. The average annual cost of production over the estimated 10-year period was $158,127 (U.S.), net operating income was $159,197 (U.S.) and the net income was $49,244 (U.S.). The average annual pearl production of 28 kg was higher than the break-even production of 15 kg. The break-even price was estimated at $6.60 (U.S.) per gram of pearl. Net Present Value (NPV) was estimated at $137,416 (U.S.) and the Benefit Cost Ratio (BCR) at 1.20 (20% discount rate). The Internal Rate of Return (IRR) was estimated at 28%. 相似文献
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Farming of the striped catfish, Pangasianodon hypophthalmus, is a major aquaculture activity in Bangladesh, particularly in the district of Mymensingh. However, pangasius farm management practices and the socio‐economic impacts of pangasius farming systems in Mymensingh have not yet been adequately described in the literature. This article provides an overview of the present status and characteristics of pangasius culture in Bangladesh based on data from a study conducted in Mymensingh district during 2009. The mean productivity of pangasius was 36.9 MT ha?1, where 87.9% of the farms produced between 15 and 65 MT ha?1 of pangasius, with an additional 10–20% Indian major and Chinese carps and Nile tilapia. Pangasius aquaculture in Bangladesh has improved the economic and social status of a variety of stakeholders in communities where the fish is farmed. 相似文献
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Christopher Mulanda Aura Safina Musa Ernest Yongo John K. Okechi James M. Njiru Zachary Ogari Robert Wanyama Harrison Charo‐Karisa Henry Mbugua Samson Kidera Veronica Ombwa Jacob Abwao Oucho 《Aquaculture Research》2018,49(1):532-545
Mapping of lacustrine aquaculture and socio‐economic assessment of cage farmers operations can be employed as decision support tools in an integrated fashion for fisheries management. We simultaneously mapped and reported the location of cages and characterized socio‐economic and indicators of cage farming in Lake Victoria, Kenya. Structured questionnaires and interviews from cage farmers generated socio‐economic data and management information. Vital water quality parameters were analyzed in selected sampling sites. Cage culture was found to be a male‐dominated activity with the majority of owners aged <45 years (n = 23; 59%). Siaya County had the highest cage establishments (n = 20) and number (n = 1,343). Proximity to Dominion Farm, pioneers of cage culture, as well as decreased presence of water hyacinth (Eichhornia crassipes) coverage may have contributed to high cage numbers in Siaya County. The only species cultured was Oreochromis niloticus. Most cage establishments (n = 30; 76%) were located within 200 m from the shoreline. Total operational costs for a cycle (8 months) amounted to USD 465,250 worth a total production value of USD 8,827,000, farmers often realizing a mark‐up of >100%, indicative of its robust viability within “The Blue Economy” concept. With the increasing number of cages in the lake, there is the need for policy and regulations to guide its investment, both to protect local economies through improved business practices and to ensure sustainability for the lake ecosystem due to the likelihood of exacerbation in water quality deterioration in cage culture sites. 相似文献
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Panagiotis Varvarigos 《Aquaculture International》1994,2(3):197-205
The production economics of the emerging Bulgarian private carp and trout farming industry were assessed by surveying a representative sample of 20 private and state-controlled farms as well as visiting the National Fresh Water Fish Research Institute, the state-owned fish feed production plant and a fish processing plant.The major constraints for the development of profitable fish farming were found to be the lack of capital and the insecurity of tenure, which nonetheless, do not serve to discourage new entrants into the industry. The expected gross margin per tonne of carp produced in reservoirs or earth ponds is USD 487, while a tonne of trout farmed in concrete raceways shows a gross margin figure of USD 525. State-owned trout farms are only available for outright purchase at auctions, whereas carp farms may be rented, but only for a short term.Fish farmers could benefit from organizing themselves into producer groups in order to improve marketing and secure quality inputs. In particular, there is scope to source quality dry fish diets on both economic and environmental grounds.An extension advisory service is needed to support inexperienced new entrants and researchers should urgently evaluate what seem to be the most cost-effective methods of production. 相似文献
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Asael Greenfeld Nir Becker Jennifer McIlwain Ravi Fotedar Janet F. Bornman 《Reviews in Aquaculture》2019,11(3):848-862
Aquaponics, which integrates hydroponic farming and aquaculture, has the potential for sustainably producing high‐quality food, but has yet to achieve commercial success. In recent years, however, commercial‐scale aquaponics has received considerable attention from the scientific community, with the current literature covering many aspects of aquaponic production. We reviewed this literature and classified the specific areas covered by each paper and its contribution to either cost reduction or benefit enhancement. The literature regarding the economic benefits of aquaponics was summarised, and despite contradicting views of current profitability, there is a consensus that (i) larger systems are economically superior to smaller ones; (ii) profitability is sensitive to retail prices; and (iii) commercial aquaponics are more profitable through improved business plans. This review provides a quantitative scientific analysis of the bioeconomics and potential of commercial aquaponics, useful for both researchers and practitioners. We argue for greater focus on three understudied aspects that could each be a ‘game changer’ for commercial aquaponics. These include the following: (i) grower considerations such as financial planning and risk management that affect potential growers’ initial engagement in aquaponics; (ii) consumer perception of aquaponic products including the willingness to pay more for its added value; and (iii) the economic value of the environmental benefits of aquaponic systems and ways to internalise them for profit. Further study of each of these aspects, along with the ongoing improvement of production systems, will support the establishment of large‐scale aquaponics as an economically sustainable industry. 相似文献
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三角帆蚌筛选及其产珠量分析 总被引：1，自引：0，他引：1
为了提高珍珠产量,降低生产成本,建立生产上简便易行的选蚌方法。通过三角帆蚌池塘养殖试验表明,三角帆蚌的主要生长期为4月—10月中,此期间的平均水温>20℃。对415只体长(a)(7.74±0.42)cm,体宽(b)(1.69±0.14)cm,体高(h)(3.98±0.22)cm的三角帆蚌育珠蚌进行分类统计,分析其体形与产珠量之间的关系。结果表明,三角帆蚌群体的体积(V)大于1.29■或者体长大于(1.29·(ā)~3)～1/3时,珍珠产量高于平均值50%以上。 相似文献