Effect of environmental factors such as exposure to air and desiccation, salinity, temperature, light and photoperiod on tetra spore shedding in the red alga Gracilaria crassa was studied under laboratory condition. In the tetrasporic thalli exposed to air in shade and sun for different durations, maximum quantity of spores were liberated from the thalli in submerged condition in control experiment. Spore output was observed at salinity ranging from 10 to 40% with peak output at 30%. Spore discharge was found at temperature ranging from 20 to 40' C with maximum quantity of spore liberation at 25OC. Spore shedding was recorded at light intensity ranging from 10 to 100 p Em2S-I with peak discharge at 20 p Em-2S-I. Maximum spore release occurred in long day condition at 12 : 12 LD cycle.
Digital library
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Dead zones in the coastal oceans have spread exponentially since the 1960s and have serious consequences for ecosystem functioning. The formation of dead zones has been exacerbated by the increase in primary production and consequent worldwide coastal eutrophication fueled by riverine runoff of fertilizers and the burning of fossil fuels. Enhanced primary production results in an accumulation of particulate organic matter, which encourages microbial activity and the consumption of dissolved oxygen in bottom waters. Dead zones have now been reported from more than 400 systems, affecting a total area of more than 245,000 square kilometers, and are probably a key stressor on marine ecosystems.
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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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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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Algal biomass including macroalgae and microalgae show great potential as pyrolysis feedstock in generating energy-dense and valuable pyrolytic products such as bio-oil, biochar and bio-syngas. The chemical constituents of macroalgae and microalgae show great variations, especially their lipid, carbohydrate and protein contents, which could affect the qualities of the pyrolytic products. From the established conventional pyrolysis, the products produced from both macroalgae and microalgae show moderate energy contents (< 34 MJ/kg). The review identifies the issues associated with development of conventional pyrolysis such as flash and intermediate pyrolysis. To enhance the production of biofuels from algal biomass, advanced or non-conventional pyrolysis techniques have been employed. Catalytic pyrolysis on algal biomass could reduce the nitrogenates and oxygenates in the biofuels. On top of that, co-pyrolysis with suitable feedstock shows great enhancement on the biooil yield. As for hydropyrolysis of algal biomass, their generated biofuels can produce up to 48 MJ/kg with high yield of bio-oil up to 50 wt%, comparable to conventional fuels. Microwave-assisted pyrolysis of algal biomass greatly shortens the processing time through advanced heating; however, favours the formation of bio-syngas by improving the yield up to 84 wt% depending on the feedstock used. Therefore, formation of biofuel fraction suitable for energy generation highly depends on the selected pyrolysis technologies
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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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State of the States Focus
- Farms & Landings
- Permitting & Regulations
Note: Seaweed farmers will need to obtain multiple permits and authorizations to get their farms up and running. Only the lead regulatory agency is listed for in each state.
- Post Harves
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Aquaculture is developing, expanding and intensifying in almost all regions of the world, except in sub-Saharan Africa. Global population demand for aquatic food products is increasing, the production from capture fisheries has levelled off, and most of the main fishing areas have reached their maximum potential. Sustaining fish supplies from capture fisheries will, therefore, not be able to meet the growing global demand for aquatic food. Aquaculture appears to have the potential to make a significant contribution to this increasing demand for aquatic food in most regions of the world; however, in order to achieve this, the sector (and aquafarmers) will face significant challenges. The key development trends indicate that the sector continues to intensify and diversify and is continuing to use new species and modifying its systems and practices. Markets, trade and consumption preferences strongly influence the growth of the sector, with clear demands for production of safe and quality products. As a consequence, increasing emphasis is placed on enhanced enforcement of regulation and better governance of the sector. It is increasingly realized that this cannot be achieved without the participation of the producers in decision-making and regulation process, which has led to efforts to empower farmers and their associations and move towards increasing self-regulation. These factors are all contributing to improve management of the sector, typically through promotion of “better management” practices of producers. This document analyses the past trends that have led the aquaculture sector to its current status and describes its current status globally.
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In Norway, -Seaweed Energy Solutions has signed a cooperation agreement with Statoil, in which Statoil has agreed to co-fund SES’s ongoing technology development. The agreement includes plans for a large-scale demonstration project.
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Demand for animal derived protein source is increasing owing to the increase in human population throughout the world. Agriculture which is the major source of animal protein for the world is now facing challenges owing to scarcity of adequate land and water. As demand of water to industries and household are increasing, the share of water for agriculture production is substantially decreasing particularly in arid and semi-arid zones. Thus, there is need to develop viable technologies which can sustain production. It is in this context integrated rearing system has been proposed amongst the potential alternatives. In this context the principle of integrated fish-livestock and fish-crop farming involves rearing fish besides with livestock and crop production. These systems are especially relevant for developing countries since there is limited capacity of the farming community for intensive fed aquaculture. Socioeconomic assessment on integrated aquaculture-agriculture systems in the Malawi, Ethiopia and Nigeria have showed promising results towards combating poverty and malnutrition. Thus, the emphasis in this review is centered on compiling research and development outputs in integrated aquaculture-agriculture systems in the past few decades with an anticipation of providing information for policy makers to help make evidence based decision making.
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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.