In India, the seaweeds are harvested by handpicking. In the United States rapid industrialisation has been brought 'in during 1917-1918 in harvesting the Macrocyst/s beds by mechanical harvestors (Dawson, 1966). Mathieson (1969) described the harvest of Macrocyst/s using motor-driven barges with mowers. The mechanical harvestors cut the kelp canopy just under one metre below the water surface and transport the material to the barge. This way, several hundred tons of seaweed can be cut in a day. After being harvested, the material is washed and chopped, and the algin extracted.
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Algal blooms have become a major concern in coastal areas and the great lakes of the world. Because of their various consequences for aquatic ecosystems and resources, algal blooms are called “harmful algal blooms” (HABs). HABs often become severely detrimental when they involve one ormore toxin-producing microalgae of various taxonomic origins. The accumulation of algal biomass also has deleterious effects on the ecological status of water. However, appropriate management strategies can allow the beneficial utilization of these events by consuming the biomass feedstock in the production of valuable biocommodities, including biofuels, functional food ingredients, UV-absorbing compounds, pharmaceutical products, etc. However, if the algal biomass can be harvested prior to the onset of their death phase, nutrients (carbon, nitrogen, and phosphorus) can also be removed from the ecosystem by harvesting the algal blooms. Great progress has been made in the last decade in monitoring and predicting HABs, and a demand is emerging for persuasive postevent management policies that focus on the potential utilization of these blooms as natural renewable bioresources. This review summarizes various potential applications of nuisance algal blooms and the need for scientific research into their economic and industrial potential. Major algal products with great ecological and economic significance and their contemporary global utilization are analyzed.
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The use of ionizing radiation and radioactive elements is becoming increasingly popular with the rapid developments in nuclear technology, radiotherapy, and radio diagnostic methods. However, ionizing radiation can directly or indirectly cause life-threatening complications such as cancer, radiation burns, and impaired immunity. Environmental contamination with radioactive elements and the depletion of ozone layer also contribute to the increased levels of radiation exposure. Radioprotective natural products have particularly received attention for their potential usefulness in counteracting radiation-induced damage because of their reduced toxicity compared with most drugs currently in use. Moreover, radioprotective substances are used as ingredients in cosmetic formulations in order to provide protection against ultraviolet radiation. Over the past few decades, the exploration of marine algae has revealed the presence of radioprotective phytochemicals, such as phlorotannins, polysaccharides, carotenoids and other compounds. With their promising radioprotective effects, marine algae could be a future source for discovering potential radioprotective substances for development as useful in therapeutics.
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This paper proposes a mapping model for seaweed aquaculture based on Interval Type-2 Fuzzy Sets (IT2FS) and Multi-Layer Perceptron (MLP) algorithm as a new framework to map potential area for seaweed cultivation to face uncertainty business environment. The main output of this research is a framework as a conceptual model for seaweed potential area mapping based on IT2FS and MLP; and visualization model from the proposed framework using google map API. We use MLP to learn historical data of variables that affect seaweed cultivation and predict future environment condition. The output of MLP used as input for IT2FS for inference process. The decision output from IT2FS is potential or not potential with specific prediction of production size for each region. We test our model for potential mapping in South Sulawesi’s seaweed aquaculture Indonesia. The test result shows our mapping model can provide potential area with total production size each area in South Sulawesi Indonesia.
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Seawater samples were collected from various locations along the Lebanese coast. Four unilagal isolates were acquired using streaking and serial dilution methods. The four isolates were cultured in 20 L flat photo-bioreactors containing seawater fertilized with Guillards F/2 medium. The growth dynamics, dry matter yield, lipid content, fatty acid profile and potential biodiesel yield were determined. The lipid content varied among growth phases and was greatest in the stationary phase, where it ranged between 14.5% DW in the Jod isolate and 16.5% DW in Jbd isolate. The best microalgal isolate tested gave a biodiesel production of around 50mg/ L. Optimization of culture conditions to improve biodiesel yield and the search for better performing local phytoplankton species are in progress.
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Seawater samples were collected from the coastal area along the Lebanese coast. The samples were fertilized using Guillards F/2 medium and cultured in 2 L flasks. Out of five promising blooms, three were selected and cultured in 70 L cylinders and in 300 L raceway ponds under greenhouse conditions. A culture of Chlorella “marine” was used as reference. The growth dynamics were determined and dry matter yield, lipid content, fatty acid profile and potential biodiesel yield were determined. Dry matter production varied among blooms and ranged between 455 and 641 mg/L/harvest, with the cylinders giving a 23-33% greater productivity in terms of mg dry matter/L/day. The lipid content in blooms varied between 16 and 18% DM and reached about 19% in the Chlorella isolate. In race way ponds as well as in the cylinders, two of the natural blooms yielded biodiesel in proportions similar to the Chlorella reference isolate. The Saida bloom gave a biodiesel production of 5.2 mg/L/day in cylinders and the Nahr ElKalb (NK2) bloom 4.3 mg/L/day in raceway ponds
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Pakistan has a strong potential of biodiesel production if the available feedstock resources are used sustainably and implementable policies are made in appropriate direction. To meet the energy demands and to find alternative and non-conventional resources of energy different challenges like research and development, infrastructure development, decentralized type of power delivery system, commercialization, market development, education and outreach programs, public awareness, monitoring, subsidies, government participation, technology transfer and evaluation must be considered and a comprehensive policy must also be made to systematically control and integrate them at national level. Pakistan is enriched with a wide variety of feed stocks which can be used for biodiesel production. Pakistan has an enormous potential of biodiesel production from jatropha, plants seed oil and microalgae which needs more consideration and practical applications. Harvesting the potential of microalgae for biodiesel production in Pakistan can be helpful to make it selfsufficient for energy demands. Pakistan is also facing several challenges like climate change, lack of financial resources, state of art technology and absence of appropriate government policies, which limit the commercialization of biodiesel. Although Government of Pakistan has established different institutions to promote and develop alternative energy technologies and to achieve 10% share of bioenergy in the energy sector by 2020, but still the targets are to be achieved on practical grounds. In this article, we have reviewed the potential of biodiesel in Pakistan, feed stocks, biodiesel production process, barriers and future developments. Future policies on biofuels, trends, recommendations, and the implication of existing policies are also discussed with research and developments goals for the promotion of biodiesel in Pakistan
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The supply of land-based agricultural products as aquafeed raw materials is challenged by limitations on space and water, and by environmental damage. Marine environments offer a vast opportunity for the expansion of aquaculture, including the production of feed raw materials. Besides fishmeal and fish oil, which are generated from capture fisheries, the use of marine-based feed raw materials from aquaculture production is not yet in common practice. Here, we discuss the potential of underutilized marine organisms that can be cultured by extracting nutrients from their environment and are nutritionally compatible for use as alternative feed materials in aquaculture. We identify marine organisms such as blue and green mussels, Ulva spp., and microbial floc that are nutritionally suitable as aquafeed raw material and may further act as bioremediators. However, environmental factors that affect productivity and the risk of pollutant accumulations, which would potentially reduce the safety of aquaculture products for human consumption, may pose challenges to such applications of extractive organisms. Therefore, the development of pretreatment and processing technologies will be critical for improving the nutritional quality and safety of these raw materials for aquafeed production.
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There is increasing interest in use of‘alternative’soil amendments in agriculture, but the wide range of resourcesand products available differ greatly in their potential to overcome soil constraints and improve nutrient useefficiency. The three main types of biological amendments can be categorised as biostimulants, organicamendments and microbial inoculants. Many have potential to influence biological, chemical and physicalconditions of soil, but most are not well researched or easily used in agriculture. The main exception is legumeinoculants, which are very well researched and contribute enormously to agricultural productivity when le-gumes are incorporated into farming systems. Biostimulants include amino acids, chitosan, seaweed extracts andhumic substances. Organic amendments include manures, composts, compost derivatives and biochars.Microbial inoculants include specific bacterial inoculants for legumes, and less specialised rhizosphere bacteria,arbuscular mycorrhizal fungi, ectomycorrhizal fungi and a range of disease suppressing microorganisms. Somebiological amendments applied to soil may be more effective when used in combinations rather than singly.Furthermore, those used over longer periods may have potential for cumulative effects not captured when usedover shorter timeframes. Such differences in effectiveness would occur primarily where benefits involve mi-crobial interactions with chemical and physical soil processes leading to slow transformations within the soilmatrix that influence soil fertility and soil health. Similarly, addition of manures and composts may requireseveral years for any quantifiable increase in soil organic C. Although considerable knowledge of the modes ofaction of many biological amendments is available, their performance underfield conditions is usually less wellunderstood. The wide variety of natural and manufactured products available in most cases precludes adequatepeer-reviewed research to support claims about their effectiveness. This can lead to proliferation of un-substantiated assertions of efficacy. This review highlights the lack offield-scale evidence of benefits for manybiological amendments with potential to be used in agriculture. We propose complementary approaches of (i)laboratory- or glasshouse-scale research to understand modes of action, and (ii) targetedfield-scale participatoryresearch involving groups of farmers using on-farm trials as a forward pathway. Use of biological amendments toovercome soil constraints is expected to expand with intensification of agriculture and as a result of climatechange. Therefore, information that enables farmers to discriminate among products that have different levels ofeffectiveness is necessary, and on-farm participatory research should contribute to addressing this need.
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The large amount of cellulose found in Ulva sp. and its low percentage of lignin-like compounds make it an interesting raw material for partially substituting wood pulp to produce pulp and paper. This work shows the suitability of mild chemical treatments for papermaking using residual biomass from this green seaweed, harvested on the beaches, in order to give it added value. A chemical characterization was used to determine ethanol-benzene, hot water, and 1% soda extractives, ash content, holocellulose, α-cellulose, and acid-insoluble material. Cellulose extraction was performed with low proportions of soda and hydrogen peroxide, and it was subjected to a refining step. A design of experiments was used to explain the influence of soda (6%, 8%, and 10%) and hydrogen peroxide (2%, 4%, and 6%) based on oven-dry weight, plus refining (1000 PFI revolutions, 3000 PFI revolutions, and 5000 PFI revolutions). The results showed that to attain good paper strength, it is advisable to operate at maximum alkali charge, minimum peroxide concentration, and refine to a high degree.
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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.