Aspects of the nutrient-uptake physiology of Porphyra dioica (Brodie et Irvine) from Porto, Portugal were investigated under laboratory conditions. The capacity for uptake and accumulation of nitrogen (N) by P. dioica was determined for two different N sources, ammonium 
and nitrate (
). The influence of the light–dark cycle and of the simultaneous presence of 
and 
, as well as the effects of phosphorus (P) enrichment, on the growth, nutrient uptake, and accumulation were also evaluated. Porphyra dioica was able to take up, accumulate, and grow equally well using both sources of nitrogen when presented separately. The photosynthetic pigment levels increased significantly with the increase of the availability of N, for both sources. The chlorophyll a content was higher in thalli that used 
as source of N, while this difference was not seen for phycobiliprotein content. When both N sources were available (NO3 : NH4 = 6 : 1), P. dioica preferentially removed 
, with a clear diurnal difference. During the light period, the algae removed 70% of the 
available, while only 35% was removed during the dark period. Phosphorus enrichment did not influence the growth rate or the amount of P removed from the medium, suggesting a limited capacity to store P. These results indicate that P. dioica is a good candidate for application in an integrated multi-trophic aquaculture (IMTA) system.
Digital library
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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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Accurately determining protein content is important in the valorization of algal biomass in food, feed and fuel markets. Conversion of elemental nitrogen to protein is a well-accepted and widely practiced method, but depends on developing an applicable nitrogen-to-protein conversion factor. The most complete method to determine this factor takes six different hydrolyses of the subject material and these are not always carried out in reported literature studies. We report new data for conservative conversion factors determined from 21 algae samples along with over 50 amino acid profiles from the literature, representing distinct cultivation conditions for fresh and marine algae. We find that the amino acid profile among different algae samples is consistent, however the large variability between strains in non-protein nitrogen (up to 54% in microalgae) causes variability in the calculated conversion factor. We include our calculated novel nitrogen-to-protein conversion factors for model and commercially relevant biofuel algal strains and compare these with the literature.
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The oceans and Great Lakes support the lives, lifestyles, and livelihoods of all Americans. We fish from their waters, vacation on their edges, ship cargo on their surface, and extract oil, gas, sand, and gravel from their seafloors.
Ocean and Great Lakes-dependent activities are important contributors to the nation’s economy. Oil and gas production provides energy. Seafood production and processing meet the demands of restaurants and seafood markets. Tourism and recreation support millions of part-time and entry-level jobs. Marine construction, marine transportation, and ship building provide access to global markets.
The oceans and Great Lakes also provide a wide range of benefits that, although real and fitting for economic consideration, do not lend themselves to traditional measures of jobs, wages, and gross domestic product. Coastal and ocean ecosystems sequester carbon from the atmosphere, protect communities from the harmful effects of coastal storms, and provide myriad other benefits that support human life and well-being.
This report provides insights into the benefits derived from the oceans and Great Lakes that result in jobs and wages and that contribute directly to the nation’s gross domestic product. This focus should not be understood to mean that the benefits whose footprints show up well in market data are the largest or most important ones. Instead, data presented in this report should be taken for what they are—indicators of the impacts that oceans and Great Lakes resources and ecological systems have on the market economy of the United States, viewed through the lens of nationally consistent data produced by federal agencies.
Data presented in this report are from the National Oceanic and Atmospheric Administration’s Economics: National Ocean Watch (ENOW) data set. ENOW data are produced by NOAA in partnership with the Bureau of Economic Analysis, Bureau of Labor Statistics, and Bureau of the Census, and are derived from some of these agencies’ most respected and commonly used data.
The consistency of ENOW’s representation of the ocean economy with these data sets is one of its primary advantages. Another is the fact that it is produced in a manner that yields results that are comparable across time and from place to place. ENOW data are available for the years 2005 through 2014 for about 400 coastal counties, 30 coastal states, 8 regions, and the nation.
The ocean economy, as represented in the ENOW data, includes six economic sectors that depend in various ways on the oceans and Great Lakes:
- living resources
- marine construction
- marine transportation
- offshore mineral extraction
- ship and boat building
- tourism and recreation
A review of this list underscores the complexity and importance of effective use, management, and governance of the oceans and Great Lakes. Some economic activities, like commercial fishing (part of the living resources sector), depend on the health of coastal and ocean ecosystems. Yet all of the sectors include activities that have the potential to harm these ecosystems, putting jobs, wages, and gross domestic product (as well has human life and wellbeing) at risk.
Maintaining the strength and sustainability of these ocean-based activities requires that we exercise good stewardship and care for the systems that support them.
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The Hawaiian green turtle, Chelonia mydas Linnaeus, is a marine herbivore known to feed on sea grasses and seaweeds. On the east side of the island of Hawai‘i, at high tide, green turtles have been observed feeding on a terrestrial, salt-tolerant turfgrass: seashore paspalum, Paspalum vaginatum Swartz, first introduced to the Hawaiian Islands in the 1930s. The role of this grass in green turtle nutrition is unknown. Paspalum vaginatum samples were collected at Keaukaha Beach Park, Hilo, and analyzed for nutritional composition (percentage water, percentage ash, caloric value, C:N ratio, percentage protein, and percentage lignin). In addition, two red seaweeds, Pterocladiella capillacea (Gmelin) Santelices & Hommersand, a common food source for green turtles, and Ahnfeltiopsis concinna (J. Agardh) Silva & DeCew, an abundant high-intertidal species sometimes consumed by turtles, were analyzed for comparison. In contrast to the two seaweed species, Paspalum vaginatum contained approximately half the ash; 300–1,500 more calories/g ash-free dry weight; three to four times greater total protein; and 3–19 times higher lignin content. Green turtles in Hawai‘i may opportunistically consume P. vaginatum because of its local abundance and/or its high protein and caloric content. In foraging areas where native macroalgal species have declined and/or turtle carrying capacity has been reached, green turtles may exploit new foods, such as seashore paspalum, and perhaps mitigate decline in somatic growth rates and body condition.
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Positive comments from ZERO in NRK about SES' involvement in bioenergy. Scientists believe that Norway can conquer the European biofuels market with fast-growing kelp from the Trøndelag coast.
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SINTEF, the largest independent research organisation in Scandinavia, has been working for some years to develop a national seaweed culture program. Now SINTEF has established the Norwegian Seaweed Technology Centre in its Fisheries and Aquaculture Institute near Trondheim, Norway. A staff of about a dozen people is devoted to the centre's main objective: the development of commercial-scale cultivation of seaweed for the production of biofuels.
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Seaweed Energy Solutions AS (SES) has reached an agreement to acquire 100 percent of Denmark\'s Seaweed Seed Supply AS, a move that sharply reinforces SES\' position as Europe\'s leading player in large-scale seaweed cultivation for renewable energy and other uses, including feed.
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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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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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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.