FAO fisheries fact sheet on Laminaria japonica (Areschoug, 1851), also called kombu or Japanese kelp.
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This work developed a laboratory prototype methodology for cost-effective, water-sparing drip-irrigation of seaweeds, as a model for larger-scale, on-land commercial units, which we envision as semi-automated, inexpensive polyethylene sheet-covered bow-framed greenhouses with sloping plastic covered floors, water-collecting sumps, and pumped recycling of culture media into overhead low-pressure drip emitters. Water droplets form on the continually wetted interior plastic surfaces of these types of greenhouses scattering incoming solar radiation to illuminate around and within the vertically-stacked culture platforms. Concentrated media formulations applied through foliar application optimize nutrient uptake by the seaweeds to improve growth and protein content of the cultured biomass. An additional attribute is that seaweed growth can be accelerated by addition of anthropogenic CO2-containing industrial flue gases piped into the head-space of the greenhouse to reuse and recycle CO2 into useful algal biomass. This demonstration tested three different drip culture platform designs (horizontal, vertical and slanted) and four increasing fertilizer media concentrations (in seawater) for growth, areal productivity, and thallus protein content of wild-collected Ulva compressa biomass, against fully-submerged controls. Cool White fluorescent lights provided 150–200 μmol photon m-2 s-1 illumination on a 12/12 hr day/night cycle. Interactive effects we tested using a four-level single factorial randomized block framework (p<0.05). Growth rates and biomass of the drip irrigation designs were 3–9% day-1 and 5–18 g m-2 day-1 (d.w.) respectively, whereas the fully-submerged control group grew better at 8–11% per day with of 20–30 g m-2 day-1, indicating further optimization of the drip irrigation methodology is needed to improve growth and biomass production. Results demonstrated that protein content of Ulva biomass grown using the vertically-oriented drip culture platform and 2x fertilizer concentrations (42:16:36 N:P:K) was 27% d.w., approximating the similarly-fertilized control group. The drip methodology was found to significantly improve gas and nutrient mass transfer through the seaweed thalli, and overall, the labor- and-energy-saving methodology would use a calculated 20% of the seawater required for conventional on-land tank-based tumble culture.
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We present the results from sustained tonne-quantity production of two novel strains of marine microalgae, the diatom Staurosira and the chlorophyte Desmodesmus, cultivated in a hybrid system of 25-m 3 photobioreactors and 400-m 2 open ponds at a large-scale demonstration facility, and then apply those results to evaluate the performance of a 100-ha Base Case commercial facility assuming it were built today. Nitrogen fertilization of 2-d batch cultures in open ponds led to the greatest yields – from both species – of ~75 MT ha −1 yr −1 biomass, and ~30 MT ha −1 yr −1 lipid, which are unprecedented in large scale open pond systems. The process described here uses only seawater, discharges no nitrogen or phosphorus in any form, and consumes CO 2 at 78% efficiency. We estimate the capital cost of a 111-ha Base Case facility at $67 million in Hawaii, where actual production was performed, and $59 million on the Gulf Coast of Texas. We find that large-diameter, large-volume PBRs are an economical means to maintain a continuous supply of consistent inoculum for very short-period batch cultures in open ponds, and thus avoid biological system crashes that otherwise arise in longer-term pond cultures. We recommend certain improvements in cultivation methods that could realistically lead to yields of 100 MT ha − 1 yr −1 biomass and N 50,000 L ha −1 yr −1 algal oil. Comprehensive techno-economics and life cycle assessment of 20 end-to-end production lineups, based on the cultivation results in this paper, are presented in a companion paper by Beal et al. [1].
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In recent years the farming of sandfish (Holothuria scabra) has been adopted by a number of farmers in south-central Vietnam. Hundreds of thousands of hatchery-produced juvenile sandfish have been stocked into ponds in the region. Broodstock were collected from the wild in Khanh Hoa province and from commercial culture ponds at 40–500 g weight. The broodstock were stored in a holding pond at a low density without adding feed. Animals of average weight (~350 g) were then transferred to conditioning tanks about 1 month prior to spawning. Indoor conditioning tanks were prepared with a sandy substrate and sand-filtered water supply. The animals were fed with fine shrimp feed. Simplified hatchery methods using cheap and basic equipment have been refined over the past decade, and consistent batches of juveniles can now be produced at will, with around 50,000 competent juveniles produced from batches of 2 million eggs.
Sandfish were cultivated in ponds with muddy-sand or coral-sand substrates using simplified techniques and locally developed management methods. The results of model sandfish culture ponds in three provinces proved that these methods can be profitable for farmers in these coastal areas. The constraints to commercial sandfish pond culture in Vietnam are no longer pond management or the price paid by the dealers, but density limits and culture duration.
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Background: The Swahili people in Zanzibar have traditionally depended heavily on sailing and fishing in the waters of the Indian Ocean for livelihood. Zanzibar’s marine and coastal environments are comprised of an interconnected variety of complex ecosystems. These ecosystems have supported and shaped the local culture, economy and social well-being of coastal Zanzibaris. The healthy functioning and continuous provision of goods and services by Zanzibar’s marine ecosystems rely on the wise management and protection of its essential habitats and resources. A few key actions are required to ensure that the direct and indirect benefits provided by the ocean are maintained into the future. Perhaps one of the most critical needs is to strengthen the legal and institutional framework for sustainable management and protection of marine and coastal resources and to ensure effective implementation of the laws and regulations.
Objectives: The aim of this task was to study the legal and institutional framework and make recommendations for effective management of marine managed areas in Tanzania. This report has as a point of departure, a synthesis report on options for a national system of MMA networks for the United Republic of Tanzania, as well as a report on the legal and institutional framework for MMA management in mainland Tanzania.
Findings: The review revealed that coastal and marine resources in Zanzibar are under increasing threats due to ever increasing numbers of resource users with competing interests. A number of policy, legal and regulatory tools exist to support marine conservation in Zanzibar. The primary legal tool for managing the MMAs in Zanzibar is currently the Fisheries Act of 2010, which provides for the establishment of the Marine Conservation Unit (MCU) under the Department of Fisheries Development in the Ministry of Livestock and Fisheries. The Fisheries Act will be operationalized through the finalization and adoption of the draft MCU Regulations. The MCU is a relatively young institution and as such, is still in the process of strengthening its institutional core and management capability. Zanzibar has increased the area of the territorial seas under formal protection substantially over recent years. A great deal more resources, capacity development and skilled staffing are required for the MCU to be able to fulfil its stated mandate and responsibilities as a conservation coordination unit for all marine managed areas in Zanzibar. The draft framework Environmental legislation - the Environmental Management for Sustainable Development Act, provides a useful framework for establishment of a system of MMA network in Tanzania. Some of the key challenges to the effectiveness of implementing and enforcing legal and regulatory framework include operational challenges and a trend towards centralization of decision-making. The institutional framework for MMAs in Zanzibar is both multi-sectoral and multi-scaled across the central government and local government authorities.
Conclusions: The research undertaken to inform the development of this report has revealed that a great deal of progress has been achieved by Zanzibar over the last decade in strengthening the framework for marine and coastal conservation. A good trajectory has iv been laid towards the establishment of significant areas of protection and in putting in place the institutional and legal building blocks for improved governance of the marine ecosystems and resources. That said, a concerted effort will be needed by the government to ensure that the MCAs do not simply remain paper parks and that the ever-increasing range and number of threats from growing numbers of resource users, inappropriate coastal development, climate variability and change to name a few. It will be critical to ensure finalization and proper implementation of the GMPs for the existing MCAs as well as development of additional GMPs for the proposed MCAs. In particular, rollout of the zoning schemes in each of the MCAs will go a long way towards achieving some of the management priorities contained in the plans and yielding valuable benefits to resource users over time.
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Leroy Seafood Group and environmental group Bellona have launched a new company, Ocean Forest.The company will farm salmon alongside seaweed and mussels.According to Leroy, large-scale cultivation of algae and shellfish will help reduce climate chance through their ability to absorb CO2. Ocean Forest aims to design and construct production plants that remove more CO2 than they generate and develop future solutions through synergies between biology and technology.
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In the Far East and Pacific Islands, there has been along tradition of consuming seaweed as sea vegetables, while in Western countries the main use of seaweed has been as source of phycocolloids (alginate, carrageenan and agar) used as thickening and gelling agents in various industrial applications, including food processing.
Seaweed is also a source of compounds with protective health effects. The beneficial effects of seaweed on human health appear to derive from the presence of three categories of constituents (fibre, proteins and minerals) as well as metabolites with antioxidant properties, including carotenoids, polyphenols, vitamins and polyunsaturated fatty acids.
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Drawing on a case study in Germany, this contribution explores the practical application of offshore aquaculture within offshore wind farms in view of the different stakeholders involved. Using a transdisciplinary research approach, an understanding of the rationalities and interests among the different involved stakeholder groups was explored. Offshore wind energy is high on the political agenda in Germany. The vast spatial requirements however inherit potential user conflicts with competing, and under current legislation excluded users such as fishermen. Solutions for combining sustainable uses of the same ocean space have thus seen increasing interest within the research community in Germany and in Europe over the past years. This paper was inspired by and presents the outcomes of a stakeholder analysis and in particular a stakeholder workshop. Central focus was placed on academics and private as well as public stakeholders engaged in current research efforts of combining offshore wind farms and aquaculture in the German North Sea. The paper identifies the overall acceptance of such a multi-use scenario in society, opportunities and constraints as perceived by the stakeholders, and key research gaps. The results confirm the assumption that there is a clear need, and also willingness on behalf of the policy makers and the research community, to find sustainable, resource- and space-efficient solutions for combined ocean use.
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Background: Common cold is caused by a variety of respiratory viruses. The prevalence in children is high, and it potentially contributes to significant morbidity. Iota-carragenan, a polymer derived from red seaweed, has reduced viral load in nasal secretions and alleviated symptoms in adults with common cold.
Methods: We have assessed the antiviral and therapeutic activity of a nasal spray containing iota-carrageenan in children with acute symptoms of common cold. A cohort of 153 children between 1-18 years (mean age 5 years), displaying acute symptoms of common cold were randomly assigned to treatment with a nasal spray containing iota-carrageenan (0.12%) as verum or 0.9% sodium chloride solution as placebo for seven days. Symptoms of common cold were recorded and the viral load of respiratory viruses in nasal secretions was determined at two consecutive visits.
Results: The results of the present study showed no significant difference between the iota carrageenan and the placebo group on the mean of TSS between study days 2-7. Secondary endpoints, such as reduced time to clearance of disease (7.6 vs 9.4 days; p = 0.038), reduction of viral load (p = 0.026), and lower incidence of secondary infections with other respiratory viruses (p = 0.046) indicated beneficial effects of iota-carrageenan in this population. The treatment was safe and well tolerated, with less side effects observed in the verum group compared to placebo.
Conclusion: In this study iota-carrageenan did not alleviate symptoms in children with acute symptoms of common cold, but significantly reduced viral load in nasal secretions that may have important implications for future studies.
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Using the red alga Polyneura hilliae as an example, the minimum time taken for lethal temperature exposure, with no regeneration capacity left, was 2 weeks. Employing this exposure time, the upper temperature limits of the following 13 red algal species belonging to four biogeographical distribution groups were determined:Callophyllis lacinita, Polyneura hilliae, Hypoglossum hypoglossoides, Halurus equisetifolius, Lomentaria articulata, Cryptopleura ramosa, Calliblepharis ciliata (warm-temperate Mediterranean-Atlantic group);Callithamnion tetragonum, Lomentaria orcadensis (amphiatlantic-temperate group);Grinnellia americana, Lomentaria baileyana, Agardhiella subulata (northeast American tropical-temperate group),Solieria tenera (amphiatlantic tropical-temperature group). Pre-incubation temperatures of 10 and 20°C for one month (or 15 and 25°C for the two last-mentioned distribution groups) did not measurably affect the critical survival temperature.
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Marine Agronomy Group, CAFNRM, UH-Hilo
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