Changes in blade morphology of Saccharina latissima may be of importance for its commercial cultivation. Blade features were compared between the cultivation in horizontal rope and in hanging rope during its reproduction period (early autumn and early spring of next year). Cultivation experiments were conducted from February on a sheltered coastal area of a bay of Galicia (N.W. Spain). According to the results, the morphological differences were significant in area of blade which affected to blade biomass, although only significantly during the reproduction period of early spring. Moreover, the cultivation method significantly affects always significantly to “substantiality value”, an index that express the blade quality for human consumption. The variation in morphological features of S. latissima blade seems that were caused by different hydrodynamics of both cultivation methods.
Digital library
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The U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), is focused on creating domestic seafood supply to meet the growing demand for all seafood products. Currently, over 70% of the seafood Americans consume is imported, and at least 40% of those imports are farmed seafood. Domestic aquaculture can be an effective option to reduce dependence on seafood imports, provide jobs for economically depressed coastal communities, and increase regional food supply and security. As it develops, offshore aquaculture will be one component of the broader NOAA Aquaculture Program, which currently addresses coastal and onshore marine shellfish and finfish farming. NOAA’s Aquaculture Program also includes stock enhancement research and hatchery activities that support commercial and recreational fishing, endangered species restoration, and habitat restoration.
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The U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), is focused on creating domestic seafood supply to meet the growing demand for all seafood products. Currently, over 70% of the seafood Americans consume is imported, and at least 40% of those imports are farmed seafood. Domestic aquaculture can be an effective option to reduce dependence on seafood imports, provide jobs for economically depressed coastal communities, and increase regional food supply and security. As it develops, offshore aquaculture will be one component of the broader NOAA Aquaculture Program, which currently addresses coastal and onshore marine shellfish and finfish farming. NOAA’s Aquaculture Program also includes stock enhancement research and hatchery activities that support commercial and recreational fishing, endangered species restoration, and habitat restoration.
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Twenty years ago, offshore aquaculture – fish and shellfish farming in U.S. federal waters – was an emerging technology with tremendous potential. The United States and other countries were at the forefront of an engineering and technology revolution, much like the old race to the moon. Bit by bit, scientists, engineers, and researchers began to figure out the “how” for this type of aquaculture. They developed dependable cage systems, remote feeders, monitoring systems, and broodstock for species that would thrive in the open ocean environment. Every success fueled more interest. The potential for this type of seafood production was obvious – so were the challenges. Could this type of aquaculture be brought online safely as a way to complement wild harvest? Would it be economically viable? What about license to operate?
Today, aquaculture in federal waters is among the most talked-about technologies associated with the future of seafood production in the United States. This recent wave of interest in the offshore has strong roots in Chapter 24 of the U.S. Commission on Ocean Policy’s September 2004 report to Congress, An Ocean Blueprint for the 21st Century. In its report, the Commission recommended that the National Oceanic and Atmospheric Administration (NOAA) develop a comprehensive, environmentally sound permitting and regulatory program for marine aquaculture.
In December 2004, the Administration responded to Commission recommendations with the President’s Ocean Action Plan. That plan specifically called for national legislation to allow aquaculture in U.S. federal waters. The Administration’s legislative proposal to establish a regulatory framework was submitted to Congress in 2005 and again in 2007. The latter proposal also calls for an expanded research program for all of U.S. marine aquaculture.
The introduction of national legislation for marine aquaculture garnered attention in the media and spawned a useful and ongoing national debate about the role of domestic aquaculture in America’s seafood supply. That debate centers around a host of marine management, economic, environmental, conservation, health, social, and regulatory issues. It also includes the eventual design of aquaculture regulations for federal waters and associated federal programs. As the agency at the center of the debate, and the one that would likely be tasked with developing and implementing any new federal regulations, NOAA commissioned a study group composed of fisheries resource economists and business experts to address key economic issues associated with offshore marine aquaculture. That effort resulted in this report, Offshore Aquaculture in the United States: Economic Considerations, Implications & Opportunities.
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The U.S. Department of Energy Advanced Research Projects Agency for Energy (ARPA-E) funded our team to grow seaweed-for-biofuel inexpensively and sustainably. We also found a way to feed the world with shellfish and finfish grown on huge floating flexible reefs without using fishmeal and while simultaneously growing seaweed. I'm Kelly Lucas, Director of the Thad Cochran Marine Aquaculture Center, Gulf Coast Research Laboratory, at the University of Southern Mississippi. I will :
• Introduce our team
• Explain our aquacultural revolution
• Describe how nutrient cycling sustains the revolution
• The features of the reef designed for the Department of Energy
• Benefits of the revolution and the
• Economics.
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The red algae Gracilaria edulis, Hypnea valentiae, Acanthophora spicifera and Sarconema indica have been observed to occur and grow in a culture pond. Over a period of eight months, the algae grew to 104 kg in the pond of 800 sq m. The hydrological conditions in the pond are compared to those in the sea containing natural beds of these algae during the period of observations. This occurenceand growth may open up the possibility of growing thses algae in culture ponds providing the requisite hydrological and nutrient conditions.
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In terrestrial plants, it is well known that genetic diversity can affect responses to abiotic and biotic stress and have important consequences on farming. However, very little is known about the interactive effects of genetic and environmental factors on seaweed crops. We conducted a field experiment on Gracilaria chilensis to determine the effect of heterozygosity and nutrient addition on two southern Chilean farms: Ancud and Chaica. In addition to growth rate and productivity, we measured photosynthetic responses, photosynthetic pigment concentration (chlorophyll a and phycobiliproteins), C:N ratio (C:N), and epiphytic load. Nutrient addition affected the growth rate, productivity, phycobilin and C:N content, but not the epiphytic load. These results were independent of the heterozygosity of the strains used in the experiments. Interestingly, depending on the sampled sites, distinct photosynthetic responses (i.e., maximal quantum yield, Fv/Fm and maximal electron transport rate, ETRmax) to nutrient addition were observed. We propose that thallus selection over the past few decades may have led to ecological differentiation between Gracilaria chilensis from Chaica and Ancud. The lack of effect of heterozygosity on growth and physiological responses could be related to the species domestication history in which there is a limited range of genetic variation in farms. We suggest that the existing levels of heterozygosity among our thalli is not sufficient to detect any significant effect of genetic diversity on growth or productivity in Metri bay, our experimental site located close to the city of Puerto Montt, during summer under nitrogen limiting conditions.
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Genetic study of haploid organisms offers the advantage that mutant phenotypes are directly displayed, but has the disadvantage that strains carrying lethal mutations are not readily maintained. We describe an approach for generating and performing genetic analysis of diploid strains of Chlamydomonas reinhardtii, which is normally haploid. First protocol utilizes self-mating diploid strains that will facilitate the genetic analysis of recessive lethal mutations by offering a convenient way to produce homozygous diploids in a single mating. Second protocol is designed to reduce the chance of contamination and the accumulation of spontaneous mutations for long-term storage of mutant strains. Third protocol for inducing the meiotic program is also included to produce haploid mutant strains following tetraploid genetic analysis. We discuss implication of self-fertile strains for the future of Chlamydomonas research.
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Aquaculture continues to be the fastest-growing food production sector with great potential to meet projected protein needs. The scientific and business communities are responding to the challenges and opportunities inherent in the growing aquaculture sector with research efforts generating novel technologies that mirror the diversity of the industry. In genetics and breeding, the pace of advancement and innovation has been increasing exponentially.
The number of breeding programmes, diversity of species, target traits and efficiency and sophistication of techniques applied continues to expand and advance. However, the pace of scientific development has at times outdistanced our ability to analyze risks and benefits, develop appropriate culture and containment technologies, educate and communicate, and reach policy and regulatory consensus. Now, more than ever, efforts must be made for society to accurately analyze and understand risks, to capture opportunities to raise healthier aquatic organisms faster with less environmental impact, while improving economic stability and providing associated social benefits. Disease outbreaks continue to constrain aquaculture sustainability. Improvements in aquatic animal and plant health are coming from new technologies, improved management strategies and better understanding of the genetic and physiological basis of immunity. Vaccine development is benefiting from better specific antigen determination, more efficacious adjuvants and enhanced vaccine delivery.
Traditional diagnostic technologies and newer methods have greatly improved speed, specificity and sensitivity. Research on improving oral delivery and disease management strategies that focus on prevention offer opportunities for improved control of pathogens and parasites in the future, obviating the use of antibiotics and chemotherapeutants. An important key to culture of any fed species is the development of sustainable, cost-effective and nutritionally complete feeds, along with efficient feed management systems. Current research is focusing on improved understanding of nutritional requirements, nutrient availabilities and cost-effective formulations designed to maximize food conversion efficiency. Continuing cost pressures and the acute need to find additional protein and lipid sources to augment limited fishmeal and fish oil supplies is driving an increased understanding of how different nutrients are utilized and how to use increasing amounts of terrestrial ingredients. New sources of proteins and lipids from algae and microbes can offer alternatives, as cost efficiencies improve.
Use of enzymes, probiotics and prebiotics, phytogenic compounds and organic acids are being shown to change gut microflora and improve health, digestibility and performance. Improved pelleting and extrusion technologies allow the production of top-quality feeds. Advancements in production systems, including recirculation technologies, cages and integrated multi-trophic aquaculture, are also contributing to industry expansion and sustainability. All of these production system technologies are benefitting from expanding information and communication systems which are enabling advances in every stage of production. These and other examples suggest some of the benefits that future scientific-based innovation will contribute towards meeting increasing food demands, while improving social, environmental and financial sustainability of the global aquaculture industry.
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The ammonium (NH4+) and nitrate (NO3−) uptake responses of tetrasporophyte cultures from a Portuguesepopulation ofGracilaria vermiculophyllawere studied. Thalli were incubated at 5 nitrogen (N) levels, includingsingle (50μM of NH4+or NO3−) and combined addition of each of the N sources. For the combined additions,the experimental conditions attempted to simulate 2 environments with high N availability (450μM NO3−+150μM NH4+; 250μM NO3−+ 50μM NH4+) and the mean N concentrations occurring at the estuarineenvironment of this population (30μM NO3−+ 5μM NH4+). The uptake kinetics of NH4+and NO3−weredetermined during a 4 h time-course experiment with N deprived algae. The experiment was continued up to48 h, with media exchanges every 4 h. The uptake rates and efficiency of the two N sources were calculated foreach time interval. For thefirst 4 h,G.vermiculophyllaexhibited non-saturated uptake for both N sources evenfor the highest concentrations used. The uptake rates and efficiency calculated for that period (V0–4 h),respectively, increased and decreased with increasing substrate concentration. NO3−uptake rates weresuperior, ranging from 1.06± 0.1 to 9.65± 1.2μM g(dw)−1h−1, with efficiencies of 19% to 53%. NH4+uptakerates were lower (0.32± 0.0 to 5.75± 0.08μM g(dw)−1h−1) butG. vermiculophyllaremoved 63% of theinitial 150μM and 100% at all other conditions. Uptake performance of both N sources decreased throughoutthe duration of the experiment and with N tissue accumulation. Both N sources were taken up during darkperiods though with better results for NH4+.Gracilaria vermiculophyllawas unable to take up NO3−at thehighest concentration but compensated with a constant 27% NH4+uptake through light and dark periods. Ntissue accumulation was maximal at the highest N concentration (3.9± 0.25% dw) and superior under NH4+(3.57± 0.2% dw)vsNO3 (3.06± 0.1% dw) enrichment. The successful proliferation ofG. vermiculophyllainestuarine environments and its potential utilization as the biofilter component of Integrated Multi-TrophicAquaculture (IMTA) are discussed.
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Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
Contact: Marine.Agronomy.Group@gmail.com
Funding for this web portal is provided by the World Wildlife Fund and the University of Hawaii-Hilo.