This IEA Bioenergy report provides an international update on the status and prospects for using microalgae and macroalgae as feedstocks for producing biofuels and bioenergy products. The report’s scope covers algae-based options for producing liquid and gaseous biofuels, and also algae-based bioenergy in the more general context of integrated biorefineries. The IEA Bioenergy Executive Committee supported this report’s compilation and it is co-authored by members of IEA Bioenergy Tasks 34, 37, 38, 39 and 42. Even though algae remain an attractive target for bioenergy applications over the longer term because of their high photosynthetic efficiency, the near-term prospects for primary algae-based energy/fuels production are poor due to the relatively high cost of cultivating and harvesting algae. The past 6 years have nonetheless seen substantial progress in research, development and demonstration of algae-based bioenergy and bio-products. With low fossil fuel prices, the algae-based industry is increasingly focusing on manufacturing higher value (non-fuel/energy) products that can be profitable today. Algal biomass-based co-products can provide the critically needed revenue to reduce the net cost of producing algal-based biofuels. As such, a biorefinery approach appears essential to realize the full value of algal biomass. Progress in minimizing/reducing the energy, water, nutrients and land use footprints of integrated algal-based operations needs to be a primary objective of larger scale demonstrations and future research and development.
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The growing population, decreasing arable land and fresh water supply questions the sustainability of terrestrial agriculture for securing safe nutrients supply, particularly starch- an essential ingredient for all staple foods. Here, we report the isolation, characterization and offshore production assessment of native starch from green seaweed Ulva ohnoi cultivated in seawater. Starch content varied from 1.59% to 21.44% depending on growth conditions and seasons. Our results show that nutrient starvation significantly increased the starch concentration up to 21.4% on dry weight basis. The extracted fraction contained 75.45% starch, and the starch extraction yield from the U. ohnoi biomass was 50.37%. Ulva starch granules are spherical, ovoid and irregularly shaped, 5–7 μm in size. Their gelatinization temperature is 69° C and they are susceptible to α-amylase and amyloglucosidase digestion. U. ohnoi biomass cultivated offshore for 13 months showed an average starch yield of 3.43 ton/ha/ year (t·ha−1 y−1 ). This study encourages the potential use of offshore produced biomass for sustainable starch supply as an alternative to current agricultural products, the production of which requires arable land and fresh water.
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This thesis explored and documented how stakeholders are being engaged in the current permitting process and how the U.S.’s regulatory regime compares to countries with established offshore finfish facilities. The intended outcome of this thesis was to increase U.S. permitting transparency and to recommend improvements to the current regulatory regime and permitting process.
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Saccharina latissima is a perennial kelp with a circumboreal distribution from the North Pacific to the North Atlantic coasts. Our study clarified the taxonomy of the morphologically distinct Saccharina latissima forma angustissima (Collins) A.Mathieson from the low intertidal zone on exposed islands and ledges of Casco Bay, Maine, USA. To identify genetic divergence between the two morphotypes, S. latissima and S. latissima f. angustissima, we used a multilocus phylogenetic approach including nuclear-encoded internal transcribed spacer, mitochondrial cox1 and cox3, and plastidencoded rbcL gene sequences. Genetic analysis of the individual markers and combined data set using SVDquartets resulted in p-distance values for all markers of , 1%, suggesting low divergence between the two forms. However, there was as much or more genetic divergence between S. latissima and S. latissima f. angustissima as there were between other taxonomically accepted species of Saccharina. To investigate sexual compatibility between the two forms, we made reciprocal crosses of the gametophytes and observed sporophyte formation. All crosses were successfully grown to the juvenile sporophyte stage, suggesting that the two are reproductively compatible in vitro. It is unknown if the two populations freely hybridize in the field. Last, we compared wave action, the ecological factor most likely driving the unique morphology, at exposed sites with S. latissima f. angustissima and protected sites with S. latissima. The mean wave force at the exposed site was over 30 times higher in magnitude than at the protected site at 160.04 6 32.58 N and 4.75 6 6.75 N, respectively, during the summer. The significant differences in morphology, the lack of specimens with intermediate morphologies, and the results of a common garden experiment suggest that the morphological differences in S. latissima f. angustissima are heritable with a genetic basis. Therefore, on the basis of our molecular evidence coupled with ecological studies, we are elevating S. latissima f. angustissima (Collins) A.Mathieson to specific rank as S. angustissima (Collins) Augyte, Yarish & Neefus comb. nov. & stat. nov.
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Objective: Provide spatial perspectives on mariculture from a global viewpoint in the context of climate zones.
Overview of perspectives: Production; Coastline length of mariculture countries; Intensity of mariculture production; Maritime claims; Off of the Coast and Offshore Maritime Zones; Areas apt for cages and longlines; Example of access to ports and travel time/distance; Conclusions.
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The green seaweed Ulva is one of South Africa’s most important aquaculture products, constituting an important feed source particularly for abalone (Haliotis midae L.), and utilized as a bioremediation tool and other benefits such as biomass for biofuel production and for integrated aquaculture. Besides Ulva spp, Gracilaria spp. are also cultivated. Wild seaweed harvest in South Africa totals 7,602 mt, compared to 2,015 mt of cultivated Ulva. To mitigate for the reliance on wild harvesting, the South African seaweed aquaculture industry has grown rapidly over the past few decades. On-land integrated culture units, with paddle-wheel raceways, are now widely viewed as the preferred method of production for the industry. The success of seaweed aquaculture in South Africa is due to a number of natural and human (industrial) factors. The development of the seaweed aquaculture industry has paralleled the growth of the abalone industry, and has been successful largely because of bilateral technology transfer and innovation between commercial abalone farms and research institutions. In South Africa seaweeds have been used commercially as feedstock for phycocolloid production, for the production of abalone feed, and the production of Kelpak® and Afrikelp®, which are plant-growth stimulants used in the agricultural sector. Additionally, Ulva is being investigated for large-scale biogas production. The South African seaweed industry provides a template that could be used by other coastal African nations to further their undeveloped aquaculture potential.
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The major objective of this study is to provide a comprehensive evaluation of the socio-economic dimensions of seaweed farming in the Solomon Islands as part of a global review of the social and economic dimensions of seaweed aquaculture. Due to the available time and financial budget provided, the Wagina seaweed farming community, one of the four major seaweed production areas in the Solomon Islands, was selected for carrying out an indepth field survey. The selection was made in close cooperation with the Aquaculture Division of the Solomon Island’s Ministry of Fisheries and Marine Resources (MFMR).
Field survey data collected on Wagina island, Choiseul Province, has been complemented by key informant interviews including staff from relevant governmental and non-governmental institutions, agents and exporters regarding perceptions of the potential of seaweed production, its problems and possible solutions. Secondary information was researched and relevant information summarized to provide a sound historic background on the Solomon Island’s seaweed farming, in particular in view of governmental and non-governmental support in the establishment, dissemination and commercialization of seaweed farming activities and produce, marketing channels, production and farm-gate price development.
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The objective of this study was to determine the optimal blade size and timing to transplant seed-stock of Ecklonia cava Kjellman onto the reef structure. We used the modified artificial stepped reef structure. A total of 14 units (3.0 m length × 3.5 m width × 1.1 m height) were deployed 7-8 m deep under the water to examine the optimal blade size and timing to transplant seed-stock of E. cava onto the structures. Sporophytes of E. cava <1 cm in length were all died within 1 month of transplantation. The blades of 5-10 cm in length which were transplanted in March 2007 survived and grew well on the artificial reefs. Growth rates of 5-10 cm size class were higher than those of longer blade sporophytes (20-30 cm size class, transplanted in April) while the survival rates showed no difference between the classes of blade size. Both classes of 5-10 and 20-30 cm in length grew until July, and a reduction in size had occurred in September. These results indicate the importance of the blade size of E. cava and timing for successful transplantation of the seaweed on artificial reef structures.
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The domestication process of sugar kelp in the Northeast U.S. was initiated by selective breeding two years ago. In this study, we will demonstrate how obstacles for accelerated genetic gain can be assessed using simulation approaches that inform resource allocation decisions in our research. Thus far, we have used 140 wild sporophytes (SPs) that were sampled from the northern Gulf of Maine (GOM) to southern New England (SNE). From these SPs, we sampled gametophytes (GPs) and made and evaluated over 600 progeny SPs from crosses among the GPs. The biphasic life cycle of kelp gives a great advantage in selective breeding as we can potentially select both on the SPs and GPs. However, several obstacles exist, such as the amount of time it takes to complete a breeding cycle, the number of GPs that can be maintained in the lab, and whether positive selection can be conducted on farm tested SPs. Using the GOM population characteristics for heritability and effective population size, we simulated a founder population of 1000 individuals and evaluated the impact of overcoming these obstacles on genetic gain. Our results showed that key factors to improve current genetic gain rely mainly on our ability to induce reproduction of the best farm-tested SPs, and to accelerate the clonal vegetative growth of released GPs so that enough GP biomass is ready for making crosses by the next growing season. Overcoming these challenges could improve rates of genetic gain more than two-fold. Future research should focus on conditions favorable for inducing spring and early summer reproduction, and increasing the amount of GP tissue available in time to make fall crosses.
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Large-scale cultivation of seaweed has become one of the most important aquaculture activities in Malaysiawhich may help increase farmers’ incomes as well as seaweed itself can be processed into many beneficialend products. The present location of seaweed farming selected by farmers is situated close proximity tothe coastline which is between 100 and 200 m from the seashore. The unfavourable condition of sea duringrough sea with high wave and high speed of current is always a problem to the farmers since this environ-mental condition destroys their seaweed planting lines. To avoid the above problem, especially in monsoonprone area, a thorough analysis needs to be done in order to prevent environmental load from destroyingseaweed platform on its mooring line when subjected to greater stress. The main objective of this study isto perform a simulation study which will allow analysis of the best mooring system for multi-body floatingseaweed farm, together with understanding of the reliability and effectiveness of the system. This paperpresents the design of seaweed platform model with mooring assessment in order to obtain a comprehen-sive and reliable seaweed mooring platform with the aid of mooring simulation software and model tests.
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Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
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