There has been a recent resurgence in research investigating bioenergy production from algal biomass due to the potential environmental benefits in comparison to conventional bioenergy crops and conventional fossil fuels. This life cycle assessment (LCA) considered the energy return and environmental impacts of the cultivation and processing of macroalgae (seaweed) to bioethanol and biogas with a particular focus on specific species (Gracilaria chilensis and Macrocystis pyrifera) and cultivation methods (bottom planting and long-line cultivation). The study was based mainly upon data obtained from research conducted in Chile but the results can be applied to other locations where similar cultivation is feasible. Speculative data were also included to test promising data obtained from research. The results suggested that using base case conditions the production of both bioethanol and biogas from bottom planted Gracilaria chilensis was the most sustainable option due to the low input method of cultivation. Using new advances in cultivation and processing methods of long-line cultivated Macrocystis pyrifera however resulted in a much more sustainable source of bioenergy. If these methods can be proven on a large scale, the generation of bioenergy from macroalgae could be highly competitive in terms of its sustainability compared to alternative feedstocks. Future research should bear in mind that the results of this study should however be considered highly optimistic given the early stage of research.
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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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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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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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Finfish culture is a growing industry, and it causes a nutrient loading problem. To investigate the feasibility of an integrated culture of kelp and salmon, 15-cm long kelp (Laminaria saccharina) was grown in salmon culture effluent. The objectives were to test the effects of flow rate and kelp density on dissolved inorganic nitrogen removal (DIN), and DIN uptake and growth by the kelp. NH+, NO- and DIN (NH + NO ) loadings were in the ranges 6.2-25.4, 12.9-40.0, 19.7-52.7 #mol l- 1, respectively, over the experimental period.
Surplus uptake of nitrogen was not evident, because the C:N ratio (10-11) was constant in all experiments. During light periods, the kelp removed from 170-339, mol 1- h - 1, and approximately 26-40% of the incoming DIN. The DIN uptake rate, based on daylight sampling periods, ranged between 6.1-22.5 mol g- dry mass h- 1. The highest-flow rate, lowest-density tank had the highest DIN uptake rate. Debris from the fish effluent settling on the kelp thalli in the low-flow rate tanks affected uptake. Mean DIN uptake rate based on 3 days of growth for all flow-density combinations ranged between 5.4-8.3 #mol g- 1 dry mass h- . The kelp utilized NH and NO- equally.
The growth ranged between 6.5-9% d- . The biomass production ranged from 1-2 g per sampling period. The highest growth rate and biomass production were achieved by kelp in the highest-flow rate, lowest-density tank. Lower DIN concentrations due to higher DIN removal rates in the other tanks and light limitation due to self-shading in the high-density tanks were probably responsible for the reduced growth rate in these tanks.
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Thallus bits of Gracilaria edulis, G. corticata, G.crassa and Ulva lactuca were maintained in three enriched seawater growth media under laboratory conditions. Weekly observation on growth rate of these algae showed that Walne's medium enhanced Daily Growth Rate (DGR) of Ulva lactuca (54.42 f 3.82 mg/d), Gracilaria corticata (58.71 f 3.35 mg/d) and G. crassa (72.42 f 2.07 mg/d). Gran'laria edulis registered higher growth rate in PES medium (50.42 f 3.82 mg/d) than in Walne's and Gamborg media. However, addition of 2% garden soil extract to Walne's medium promoted the DGR in all the four species considerably (62.28 mg/d for Ulva, 66.71 mg/d for Gracilaria corticata, 77.71 mg/d for G. crassa and 56.29 mg/d for G. edulis). The results are compared with the growth rate of seaweeds achieved elsewhere in in situ sea farming being carried out without addition of any nutrients extraneously.
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Kelp farming, as well as the farming of various other seaweeds, is a significant and growing industry worldwide as seaweeds, especially kelp, are used for food, medicinal products, additives and bioremediation. Although the farming and use of seaweeds has a long history in many Asian and European countries, much of the rest of the world is only now recognizing the unique nutritional and health values of seaweeds. In addition to increased worldwide consumption, a recent development is the growing and harvesting of kelp for conversion to biofuels. A great deal of research is currently underway to evaluate the economics of these activities, project future demand for these algal products and to determine how best to meet increased global demand.
As the demand for kelp increases, however, relying solely on wild harvest may lead to severe declines of the natural populations such as happened in the fin fish and shellfish harvesting industries. Increased cultivation of kelp will be required to provide a consistent and traceable supply of biomass to industries that process the kelp for food or functional products. This increase in the number and size of farm sites may lead to more conflicts with fishermen, recreational boaters and waterfront land owners. These conflicts may be mitigated by an appreciation of the beneficial aspects that kelp and other seaweed aquaculture farms frequently provide such as habitat and water quality improvements.
The natural life cycle of kelp plants produces one harvestable sporophyte (adult) population per year. An advantage of farming kelp is the potential for growing more than one harvestable crop per year as well as providing the opportunity for selection of species that exhibit desired taste, vigor and resistance to biofouling.
What follows is this manual is an introduction to the processes, equipment and techniques for growing kelp from spores to harvest. Although there is significant farming of kelp worldwide, farming kelp in the Gulf of Maine has been very limited.
This manual describes the techniques developed and used successfully by Ocean Approved, LLC in conjunction with Dr. Charles Yarish and Dr. Jang Kim of the University of Connecticut to farm kelp in New England waters.
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Alaska’s burgeoning kelp farming industry has its success tied to two hatcheries and a law. Blue Evolution is working under a collaborative research and development agreement with NOAA to use the Kodiak Fisheries Research Center hatchery to grow the kelp seed that the company will supply to growers on partner farms.
“NOAA provides a space (no lease), and we capitalize the equipment,” says CEO Beau Perry. “And we work with them on various research threads.” Much of the east coast oyster industry technology was developed under this type of agreement with the NOAA facility in Connecticut in the early 1970s, Perry points out.
“Currently, there are many nascent aquaculture business across the country working with NOAA in this way,” he adds. The hatchery uses a recirculating system, and is able to utilize unused cold rooms at the facility, as opposed to water chillers. Perry estimates it has nearly 100 tanks, with capacity for several thousand spools and hundreds of thousands of feet of seeded string.
“We will certainly be pushing up against capacity as we are lowering the density of spools and tanks per cold room this season,” he explains. “But we can expand further using auxiliary space in the future.”
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PDF of pictures that shows good harvesting on a kelp farm.
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The recent expansion of kelp farming in Alaska has Julie Decker, chair of the Alaska Mariculture Task Force, excited.
“The 2018 Alaska Mariculture Development Plan aims to grow the mariculture industry in Alaska by $100 million in the next 20 years,” Decker explains. “The new applications we have seen from kelp farmers over the last two years are pretty exciting.”
Wild fish capture is still king in Alaska, where growing finfish is illegal. That leaves mariculture, the farming of all other aquatic species, to balance the highly seasonal work of ocean fishing. Oysters are the top cultured species in the state. But the industry for sugar kelp (saccharina) and ribbon kelp (alaria) is expanding.
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Marine Agronomy Group, CAFNRM, UH-Hilo
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Funding for this web portal is provided by the World Wildlife Fund and the University of Hawaii-Hilo.