Offshore Farming Research Articles

Offshore Aquaculture: I Know It When I See It

Offshore aquaculture is increasingly viewed as a mechanism to meet growing protein demand for seafood, while minimizing adverse consequences on the environment and other uses in the oceans. However, despite growing interest in offshore aquaculture, there appears to be no consensus as to what measures commonly define an offshore site or how effects of offshore aquaculture – relative to more nearshore practices – are assessed. This lack of agreement on what constitutes offshore aquaculture has the potential to convolute communication, create uncertainty in regulatory processes, and impede understanding of the ecological implications of offshore farming. To begin addressing these issues, we reviewed and analyzed biologically-focused primary and gray literature (Ntotal = 70) that categorize and quantify characteristics of offshore aquaculture from around the world. We found that many ‘offshore’ descriptions are relatively close to shore (< 3 nm) and significantly shallower (minimum depth ≤ 30 m) than may be assumed. We also uncovered an overall lack of consistent reporting of even the most common location-focused metrics (distance from shore, depth, current), a dearth of impact related studies (n = 17), and narrow scope of the studies themselves (i.e., 82% nutrient pollution). Of the finite subset of articles that investigated negative ecological impacts of offshore aquaculture, we found the probability of any measurable impact from an offshore farm appears to significantly decrease with distance from the farm (probability of measurable response at 90 m ± SE = 0.01 ± 0.03). Such general, but informative points of reference could be more robustly quantified with better systematic and standardized reporting of physical farm characteristics and a broader scope of ecological investigation into the effects of marine aquaculture. With offshore aquaculture still in its infancy, consistent metrics are needed for a comparable framework to guide sustainable offshore aquaculture research and development globally.

Potential, constrains and solutions for marine aquaculture in Kiel Bay &amp; Fjord

Marine aquaculture is facing a variety of competing uses in densely populated coastal areas such as the coast of Kiel Bay. Thus, a major barrier for extending the marine aquaculture business could be the lack of suitable space for “offshore farming”. Moreover, in public opinion the aquaculture sector is often associated with a negative image derived from environmental concerns. It might therefore be expected that planning aquaculture installations in Kiel Bay & Fjord would face resistance both from other offshore stakeholders and the public. This study therefore addressed the question whether arguments and criteria can be found that may contribute to a greater support and positive image of local aquaculture enterprise, thus fostering political support for this sector as well. Indeed, a widespread regional survey showed less public reservation towards aqua-cultural business in Kiel Fjord than initially expected. However, expanding the entrepreneurship in the regional aqua-cultural sector will only be successful if the installations can avoid a significant deterioration of the water quality in Kiel Fjord, e.g. through excessive emissions of nutrients from net cages. An important step forward toward this goal is the concept of IMTA = Integrated Multi-Trophic Aquaculture. The IMTA concept spatially integrates nutrient emitting installations such as fish net cages with installations of nutrient extracting organisms, e.g. mussels and algae. Based on spatial analyses of marine environmental parameters and through modelling of nutrient mass balances (emitted versus extracted nutrient quantities) possible locations, types and sizes of aquaculture installations can be determined.

Preliminary Assessment of Biofouling on Offshore Mussel Farms

AbstractBiofouling is a significant operational problem for the aquaculture industry globally; however, options for on‐farm management are limited. In New Zealand, the green‐lipped mussel,Perna canaliculus, has historically been cultivated at inshore locations, but increased competition for space has led the industry to develop offshore farming sites several kilometers from the coast. We hypothesize that the distance to these farm sites from coastal locations, and their placement over extensive soft‐sediment habitats, may provide a barrier to colonization by biofouling species with limited natural dispersal abilities. A study of two offshore mussel farms revealed that they supported relatively impoverished biofouling communities by comparison with inshore mussel farms and other artificial structures. Offshore sites had a relatively low number of taxa and a low prevalence of short‐dispersing organisms such as ascidians, which are a problematic group of fouling organisms in aquaculture. We suggest that newly established offshore marine farms have the potential to be kept free of a range of problematic fouling organisms, provided the introduction of such species via human transport pathways can be mitigated.

Development of a Simple and Innovative Wave Energy Harvester Suitable for Ocean Sensor Network Application

The article represents a new idea about an innovative, simple and cost effective marine energy harvester for powering offshore sensor nodes working as part of Ubiquitous Sensor Network (USN). Betterment of these aqua farms by including these into wireless sensor network so that they could be remote controlled from far land, is needed to make this offshore farming more popular. For this step to be done one major concern is the powering process of the sensor nodes used as the key part of sensing or monitoring purpose of the offshore projects. So our study focuses on the design and numerical study of a wave energy harvesting device for supplying uninterrupted electric power to offshore sensor nodes serving as part of ocean environment monitoring network or any marine aquaculture farm. Analysis of the environmental and device sizing factors that makes the efficiency to deviate, have been discussed here. It is a novel, floating type, double chambered wave energy converter that uses the Oscillating Water Column technology for conversion of wave power into electrical power.

ECONOMIC EVALUATION OF AQUACULTURE INVESTMENTS UNDER CONDITIONS OF RISK AND UNCERTAINTY IN THE MEDITERRANEAN SEA

This study aims to analyze, from a technical and ec onomic point of view, the choice between alternative investments in aquaculture under condit ions of risk and uncertainty. In particular, a comparative analysis has been conducted between an inshore and an offshore farm producing European sea bass in the Mediterranean Sea. The app lied model refers to the theory of subjective probability, assigning a different probability to e xpected incomes during the investment period. Resul ts show an economic convenience of inshore with respect to offshore farming.

Outplanting time and methodologies related to mariculture of the edible kelp Undaria pinnatifida in the Atlantic coast of Spain

Little is known about offshore cultivation of the edible seaweed Undaria pinnatifida outside Asian waters. However, currently its commercial cultivation is being considered in the North Western Atlantic coast of Spain (Galicia). The effect of outplanting time and methodologies related to the cultivation of U. pinnatifida in this area was studied. Biomass yield, morphological features, and growth rate were examined on sporophytes outplanted from October to December at the same site in a coastal bay. Experiments were conducted over two years, applying different harvesting and cultivation methods. Results indicate that the most suitable months for outplanting were October and November, with larger biomass production as well as improved sporophyte quality (i.e., morphology). Cultivations from October to December ended when most of the sporophytes had developed sporophylls (reproductive structures) and this occurred between early and late April in all the outplanting trials. The similar harvest time for all plants suggests that harvesting time is not related to outplanting period but should be mainly influenced by the photoperiod. These results suggest a single harvest as the most appropriate method. Moreover, results also showed that cultivation was successful using the two tested methods: seedling string all along the culture rope and seedling strings inserted at regular intervals into the rope. Finally, this paper also discusses the suitability of two different systems of offshore farming: in long-line and in vertical rope.

Chemometric data analysis application to Sparus aurata samples from two offshore farming plants along the Apulian (Italy) coastline

The levels of polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (DL-PCBs), non-dioxin-like polychlorobiphenyls (NDL-PCBs), and polybromodiphenyl ethers (PBDEs) in fish collected from two marine offshore farming plants were determined. Each sample was constituted by specimens of the same size collected at the same time in four different seasons along the farming year. The feeds given were of industrial origin and the plants were positioned in two different sites respectively exposed to different environmental characteristics. A chemometric approach was applied to interpret the subtle differences observed in fish body burdens across the three chemical groups taken into consideration. The approach consisted in a stepwise multivariate process including a hierarchical cluster analysis (CA) and a linear discriminant analysis (DA). The two main clusters determined by CA were subjected to the canonical DA, backward and forward selection procedures to select the best discriminative functions. A clear temporal and spatial discrimination was found among the samples. Across the three chemical groups, the monthly separation seemed to depend on the growth process and the main exposure was due to the feed. In addition, the two plants differed significantly from the environmental point of view and the most important discriminating group of chemicals were the NDL-PCBs. The approach resulted really effective in discriminating the subtle differences and in individuating suggestions to improve the quality of culturing conditions.

Environmental issues of fish farming in offshore waters: perspectives, concerns and research needs

Offshore fish farming is predicted to increase in the near future driven by the lack of coastal space. In this review I discuss the environmental issues of offshore farming from experience in coastal farms. Even more so than in coastal farms, a rapid and wide dispersal of dissolved waste prod- ucts is predicted for offshore farms. Despite wider dispersal of particulate waste products, fast sinking rates of feed pellets and faeces suggest organic enrichment of the bottom sediments in farm vicinities (hundreds of meters), although at lower loading rates than coastal farms. The benthic response to organic enrichment is unpredictable due to lack of knowledge from shelf areas. Most shelf sediments are considered carbon limited and fish farm waste products may stimulate the benthic communities, but due to the sparse abundance and absence of pollutant-tolerant benthic fauna, the capacity of ben- thic communities to assimilate organic matter may be limited. Instead, microbial decomposition of waste products could become important, leading to increased oxygen demand and accumulation of sulfides in the sediments. This may negatively affect benthic biodiversity. Interactions with wild fish (aggregation, genetic impacts, spreading of disease and parasites) are expected, but difficult to pre- dict, as the composition of species attracted to offshore farms will be different from that of species attracted to coastal farms. Escapees are potentially a high risk due to farm failure under rough weather conditions in the open sea. The carbon footprint of farming offshore will increase (transportation) and the ecological footprint (fishing feed) will remain a severe constraint, as in coastal farming. Offshore farming is subject to high costs of operation, including those for monitoring environmental conditions. Research should focus on interactions with wild fish populations, mapping of sensitive benthic habitats and experimental studies of the response of benthic habitats to organic enrichments.

The role of marine aquaculture in meeting the future demand for animal protein

AbstractFarm‐raised seafood is expected to play a major role in meeting the future demand for animal protein; however, the growth of marine aquaculture as currently practiced is constrained by space, economics and environmental concerns. For aquaculture to continue to expand, the potential of farming offshore ocean waters must be explored. Over the past decade, there has been worldwide interest in exploring the potential for offshore production, and the USA has emerged as one of the leaders in developing and demonstrating technologies for farming in the open ocean culture. Offshore research and development projects in New Hampshire, Hawaii and Puerto Rico have led to small‐scale commercial production, demonstrating that open ocean culture is indeed feasible and has great potential for future expansion. Despite the evidence that offshore farming is possible, a number of technical, economic and political challenges must be addressed before large‐scale production can be realized.

Organic waste impact of capture-based Atlantic bluefin tuna aquaculture at an exposed site in the Mediterranean Sea

A variety of pelagic and benthic parameters were measured at an aquaculture farm used for the fattening of Atlantic bluefin tuna ( Thunnus thynnus) which is located at an exposed site (700 m from the coast, average bottom depth of 45 m and average current speed of 6 cm s −1) in the Mediterranean Sea. The objective was to test whether modern off-shore tuna fattening industries can exert a sustainable organic waste impact on the receiving environment as has been reported for the offshore culture of more traditional Mediterranean species such as sparids. In the water column, the concentration of phytopigments, organic matter, heterotrophic bacteria and the taxonomic abundance of mesozooplankton (at the species level) were assessed. In the sediment, we assessed the concentration of reduced sulphur pools, phytopigments, organic matter, heterotrophic bacteria and the taxonomic abundance of meiofauna (at the taxa level) and nematodes (at the genus level). For most parameters, we found no substantial differences between farm and control sites. Deviations of farm values from control values, when they occurred, were small and did not indicate any significant impact on either the pelagic and benthic environment. Deviations were more apparent in the benthic compartment where lower redox potential values, higher bacterial production rates and a change in nematode genus composition pointed out to early changes in the sediment's metabolism. In addition, indigenous potential pathogenic bacteria showed higher concentration at the fish farm stations and were a warning of an undesirable event that may become established following aquaculture practice in oligotrophic environments. The overall data from this study provide extensive experimental evidence to support the sustainability of modern offshore farming technology in minimizing the hypertrophic-dystrophic risks associated with the rapidly-expanding tuna-fattening industry in the Mediterranean Sea.

Export Performance and Enterprise Reform in China's Coastal Provinces

Previous articleNext article No AccessExport Performance and Enterprise Reform in China's Coastal ProvincesF. C. PerkinsF. C. PerkinsEast Asia Analytical Unit, Australian Department of Foreign Affairs and Trade Search for more articles by this author East Asia Analytical Unit, Australian Department of Foreign Affairs and TradePDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Economic Development and Cultural Change Volume 45, Number 3April 1997 Article DOIhttps://doi.org/10.1086/452289 Views: 14Total views on this site Citations: 18Citations are reported from Crossref © 1997 by The University of Chicago. All rights reserved.PDF download Crossref reports the following articles citing this article:Emanuele Felice, Iacopo Odoardi, Dario D’Ingiullo The Chinese Inland-Coastal Inequality: The Role of Human Capital and the 2007–2008 Crisis Watershed, Italian Economic Journal 2 (Sep 2021).https://doi.org/10.1007/s40797-021-00169-wJaya Prakash Pradhan, Mohammad Zohair Subnational Export Performance and Determinants, Review of Market Integration 7, no.22 (Jul 2016): 133–174.https://doi.org/10.1177/0974929216653631Dr Mo Yamin, Prof Rudolf R Sinkovics, Jaya Prakash Pradhan, Keshab Das Regional export advantage of rising power SMEs, critical perspectives on international business 11, no.3/43/4 (Jul 2015): 236–258.https://doi.org/10.1108/cpoib-10-2013-0040Elisha P. Renne The Changing Contexts of Chinese-Nigerian Textile Production and Trade, 1900‒2015, TEXTILE 13, no.33 (Jan 2016): 212–233.https://doi.org/10.1080/14759756.2015.1054105Ward Warmerdam Beyond the Debates of Which is Best: Investigating the Complementarity of Chinese and Western Aid, and Possible Lessons from China’s Development, Fudan Journal of the Humanities and Social Sciences 7, no.11 (Jan 2014): 77–117.https://doi.org/10.1007/s40647-013-0005-8Joshua Abor Do export status and export intensity increase firm performance?, Thunderbird International Business Review 53, no.11 (Dec 2010): 9–18.https://doi.org/10.1002/tie.20386Lingwen Huang, Yang Yao Impacts of privatization on employment: evidence from China, Journal of Chinese Economic and Business Studies 8, no.22 (May 2010): 133–156.https://doi.org/10.1080/14765281003750199Zhibiao LIU, Qiang WU Product Quality Preference, Machinery Import and Import-induced Export, Studies in Regional Science 40, no.44 (Jan 2010): 963–975.https://doi.org/10.2457/srs.40.963A. AZADEH, G. H. ATAEI A PRINCIPLE COMPONENT ANALYSIS — NUMERICAL TAXONOMY APPROACH FOR EXPORT PERFORMANCE ASSESSMENT: THE CASE OF IRANIAN CHEMICAL UNITS, The Singapore Economic Review 54, no.0404 (Dec 2009): 689–707.https://doi.org/10.1142/S0217590809003446Robert G. Wallace Breeding Influenza: The Political Virology of Offshore Farming, Antipode 41, no.55 (Nov 2009): 916–951.https://doi.org/10.1111/j.1467-8330.2009.00702.xZhang Xiaohe The Impact of Globalisation and Labour Market Reforms in China, (Jan 2007): 49–66.https://doi.org/10.1016/B978-1-84334-217-5.50003-4Yifei SUN, Hongyang WANG DOES INNOVATION MATTER FOR EXPORT IN CHINA'S RURAL ENTERPRISES? EMPIRICAL EVIDENCES FROM JIANGSU, Asian Geographer 24, no.1-21-2 (Jan 2005): 1–15.https://doi.org/10.1080/10225706.2005.9684119Jang C. Jin On the Relationship Between Openness and Growth in China: Evidence from Provincial Time Series Data, The World Economy 27, no.1010 (Nov 2004): 1571–1582.https://doi.org/10.1111/j.1467-9701.2004.00667.xJianshu Deng, Bulent Menguc, John Benson The impact of human resource management on export performance of Chinese manufacturing enterprises, Thunderbird International Business Review 45, no.44 (Jun 2003): 409–429.https://doi.org/10.1002/tie.10088Jang C. Jin Exports and growth: is the export-led growth hypothesis valid for provincial economies?, Applied Economics 34, no.11 (Oct 2010): 63–76.https://doi.org/10.1080/00036840010025632David L Dean, Bülent Mengüç, Christopher Paul Myers Revisiting Firm Characteristics, Strategy, and Export Performance Relationship:, Industrial Marketing Management 29, no.55 (Sep 2000): 461–477.https://doi.org/10.1016/S0019-8501(99)00085-1W NAUDe The Determinants of South African Exports: An Econometric Analysis*(1), The South African Journal of Economics 68, no.22 (Jun 2000): 103–113.https://doi.org/10.1111/j.1813-6982.2000.tb01167.xMauricio Jenkins, Felipe Larrain, Gerardo Esquivel Export Processing Zones in Central America, SSRN Electronic Journal (Jan 1999).https://doi.org/10.2139/ssrn.168174

Strategies and technologies in offshore farming

A more restrictive attitude to inshore farming, in addition to positive biological findings among offshore farmed fish, have increased the demand for suitable offshore fish farming cages/systems. To develop such a cage/system, the requirements of the fish, the fish farmer, the insurance companies, the authorities and the moorings must be considered. The existing offshore concepts can be classified into: (1) simple flexible one-net bag cages; (2) integrated stiff semi-submersible one-net bag constructions; (3) simple stiff poly-net bag cages; (4) integrated stiff poly-net bag constructions; (5) submersible and submerged cages. An example from each group is described. The Bridgestone cage and the Farmocean system, the only offshore concepts that have been in commercial use for some years, are compared with respect to strength and management. The other concepts are evaluated in various parts. A suitable offshore concept should, in general, consist of a stable, strong and safe platform that should be easy and safe to tow, moor and board. It should allow a proper attachment of the net bag (preferably round, ∼15 m deep and 5000 m 3 in volume), and guarantee its strength and shape during all weather conditions. The fish should be fed by means of a computer-controlled automatic feeder. Faster growth, lowered mortality and reduced visceral fat content are reported among offshore farmed fish compared with those farmed inshore. A lower degree of self-pollution will also be a consequence of moving larger and deeper cages/systems offshore. The tentative rules for the type approval of floating fish farming units that have been presented by “Det norske Veritas” (DnV) in Norway will be positive for the fish farming business if it starts to be valid and cover the rest of the fish farming countries. Despite the higher investment required for the offshore cages/systems, it has been indicated that there is a better economic result and that the cost of producing 1 kg of fish is lower than in conventional fish farms. As the single-net bag concept represents a lower risk for the fish farmer, insurance company and veterinary authority, it will probably be the preferred concept.

Inshore versus offshore farming

In an effort designed to detect differences between manually fed inshore farmed rainbow trout ( Salmo gairdneri R.) and automatically computerfed offshore farmed rainbow trout, an experiment (1986) was conducted at Karlshamn, Sweden, using two different sites, one inshore and one offshore. At the sheltered inshore site traditional JAMEK † † JAMEK is a trade name for a Norwegian designed square cage (system of cages). Because of its robust and simple design it has come to be one of the most popular systems in Scandinavia. (Jamek Industry A/S, Norway) cages were used, while at the exposed off-shore location a large single unit fully automated Farmocean PLAT-FARM 3500 (Farmocean AB, Sweden) was used. Out of the same population a significant number of fish were removed from the two different farms and examined for: (1) standard length vs. weight, (2) standard length vs. circumference, (3) total weight vs. viscera weight. A comparing analysis indicates that offshore farmed rainbow trout get a significantly higher ratio of useful flesh vs. viscera fat, a slimmer and more salmon-like body and in general a superior appearance. The results also indicate a lower rate of mortality amongst computerfed offshore farmed fish. Increased activity among these fish in a turbulent environment, coupled with uninterrupted feeding seems to account for these positive findings.