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  • Understanding the Interaction of Extractive and Fed Aquaculture Using Ecosystem Modelling

    One of the most difficult tasks resource managers face is understanding the carrying capacity of coastal waters for aquaculture. Aquaculture, like many other human activities, can threathen coastal waters. Understanding eutrophication and the interaction of two diffierent types of aquaculture is very important to the safe and effective management of coastal aquaculture. The first type of aquaculture, producing shrimp and finfish depends on supplemental feeding and can contribute to eutrophication. The second type, involving bivalve molluscs and macroalgae, extracts plankton and nutrients from surrounding waters and can have a significant positive impact on moderately eutophic waters. These species depend on the water's basic productivity and will not grow effectively in water with low nutrient levels. Balancing extractive and fed aquaculture is of obvious importance to maximizing the safety and optimizing the carrying capacity of an embayment.

    Ecosystem modelling offers a three-dimensional physical, chemical and biological simulation that can help scientist and managers understand and predict the eutrophic impact of aquaculture for a specific embayment. Such a model is being explored in China in research sponsored by the Sino-US Living Marine Resources Panel. In this study, two projects are using the model to simulate the impact of aquaculture on Jiaozhou Bay, Shangdong Province, and on Xincun Lagoon, Hainan Province. Jiaozhou Bay is in the temperate zone adjacent to the Yellow Sea.

    There, a major port and industrial city, Qingdao, and scallop and shrimp aquaculture interact with the physical and biological components of the bay. The other modelled environment is very different. Xincun Lagoon is a small embayment (~22 km^2) in southeastern Hainan Island adjacent to the South China Sea. Aquaculture in Xincun Bay includes 6500 fish pens ( 3m X 3 m), 100 ha of shrimp ponds, pearl culture rafts and a new macroalgae culture operation that produced 3500 tonnes of Eucheuma in 1998-1999. The surrounding area has ~15,000 people and Xincun City is a major offshore fishing port (~500 vessels, > 10 m length) and Monkey Island Wildlife area with > 400,000 visitors annually. Extractive and fed aquaculture, along with the external activities, all have an impact on the carrying capacity of the bay for aquaculture.

    These two models show much promise for simulating local eutrophic conditions and for increasing the general understanding  of the complex interactions of aquaculture and other human activities and eventually predict carrying capacity should become useful tools for resource managers.

    Author(s): Mac V. Rawson, Jr, Changsheng Chen, Rubao Ji, Mingyuan Zhu, Daoru Wang, Lu Wang, Charles Yarish, James B. Sullivan , Thierry Chopin, Raquel Carmona

  • Understanding the recurrent large-scale green tide in the Yellow Sea: Temporal and spatial correlations between multiple geographical, aquacultural and biological factors

    The coast of Jiangsu Province in China e where Ulva prolifera has always been firstly spotted before developing into green tides e is uniquely characterized by a huge intertidal radial mudflat. Results showed that: (1) propagules of U. prolifera have been consistently present in seawater and sediments of this mudflat and varied with locations and seasons; (2) over 50,000 tons of fermented chicken manure have been applied annually from March to May in coastal animal aquaculture ponds and thereafter the waste water has been discharged into the radial mudflat intensifying eutrophication; and (3) freefloating U. prolifera could be stranded in any floating infrastructures in coastal waters including large scale Porphyra farming rafts. For a truly integrated management of the coastal zone, reduction in nutrient inputs, and control of the effluents of the coastal pond systems, are needed to control eutrophication and prevent green tides in the future.

    Author(s): Feng Liu, Shaojun Pang, Thierry Chopin, Suqin Gao, Tifeng Shan, Xiaobo Zhao, Jing Li

  • Understanding the recurrent large-scale green tide in the Yellow Sea: Temporal and spatial correlations between multiple geographical, aquacultural and biological factors

    The coast of Jiangsu Province in China e where Ulva prolifera has always been firstly spotted before developing into green tides e is uniquely characterized by a huge intertidal radial mudflat. Results showed that: (1) propagules of U. prolifera have been consistently present in seawater and sediments of this mudflat and varied with locations and seasons; (2) over 50,000 tons of fermented chicken manure have been applied annually from March to May in coastal animal aquaculture ponds and thereafter the waste water has been discharged into the radial mudflat intensifying eutrophication; and (3) free- floating U. prolifera could be stranded in any floating infrastructures in coastal waters including large scale Porphyra farming rafts. For a truly integrated management of the coastal zone, reduction in nutrient inputs, and control of the effluents of the coastal pond systems, are needed to control eutrophication and prevent green tides in the future.

    Author(s): Feng Liu, Shaojun Pang, Thierry Chopin, Suqin Gao, Tifeng Shan, Xiaobo Zhao, Jing Li

  • Understanding the recurrent large-scale green tide in the Yellow Sea: Temporal and spatial correlations between multiple geographical, aquacultural and biological factors

    The coast of Jiangsu Province in China e where Ulva prolifera has always been firstly spotted before developing into green tides e is uniquely characterized by a huge intertidal radial mudflat. Results showed that: (1) propagules of U. prolifera have been consistently present in seawater and sediments of this mudflat and varied with locations and seasons; (2) over 50,000 tons of fermented chicken manure have been applied annually from March to May in coastal animal aquaculture ponds and thereafter the waste water has been discharged into the radial mudflat intensifying eutrophication; and (3) freefloating U. prolifera could be stranded in any floating infrastructures in coastal waters including large scale Porphyra farming rafts. For a truly integrated management of the coastal zone, reduction in nutrient inputs, and control of the effluents of the coastal pond systems, are needed to control eutrophication and prevent green tides in the future.

     

    Author(s): Feng Liu, Shaojun Pang, Thierry Chopin, Suqin Gao, Tifeng Shan, Xiaobo Zhao, Jing Li

  • Understanding the sea cucumber (beche-de-mer) value chain in Fiji and Tonga

    As reported in other Pacific island communities and many countries around the world, wild stocks of sea cucumber in Fiji and Tonga are declining because of unsustainable levels of fishing. The Pacific Agribusiness Research for Development Initiative (PARDI) is a partnership involving the Secretariat of Pacific Community, the University of the South Pacific and a consortium of Australian universities, funded by the Australian Centre for International Agricultural Research. PARDI seeks to create sustainable livelihoods by identifying constraints to economic development in the Pacific islands region, and by developing appropriate technologies or products to resolve these constraints. It is currently evaluating the sea cucumber industry and its contribution to community livelihoods in Tonga and Fiji. This paper presents preliminary literature search findings of the PARDI study into sea cucumber market chains in these two Pacific island countries. Although an initial literature review revealed a scarcity of reliable information, interim maps of the current supply chains of both Fiji and Tonga have been developed and are discussed here. Research outcomes may lead to improvements in processing, value-adding to beche-de-mer and identification of new niche markets, and may facilitate investment in sea ranching and aquaculture.

    Author(s): Theo A. Simos

  • Unlocking the Sugars in seaweed to Produce Renewable Chemicals and Fuels

    A PDF Power Point on BAL's "Unlocking the Sugars in seaweed to Produce Renewable Chemicals and Fuels".

    Author(s): BAL- bio architecture lab

  • Unusual landings of agar yielding seaweed Gracilaria edulis in Kottaipattanam-Chinnamanai area

    The red seaweeds Gelidiella acerosa, Gracilaria edulis and G. crassa are used as raw materials for the production of agar by the seaweed industries in India. The demand of agar yielding seaweeds for the agar industries is more, but the quantity of G. acerosa and G. edulis exploited is less. G. edulis plants from Sri Lanka coast would have been drifted to this area by water current and it is for the first time such a large quantity of G. edulis isobserved.

    Author(s): Kalimuthu, S, Kaliaperumal, N

  • Upcycling the anaerobic digestion streams in a bioeconomy approach: A review

    Gaseous and liquid anaerobic digestion (AD) streams, currently are at best used for electricity and heat production or simply spreading at the fields, respectively. However, electricity and heat are economically produced from other renewables and advanced fertilizers are needed to avoid leaching and boost nutrients capture. Hence, AD seeks new opportunities to support circular bioeconomy. The overall objective of this review is to present state-of-the-art resource recovery routes for upcycling the AD streams to reduce carbon footprint and formulate alternative products to increase sustainability. Technical barriers and integrated systems to upcycle AD streams through biological means are presented. New technologies and methods to capture CH4, CO2 and nutrients from the digested residual resources are presented, as a) methanotrophs cultivation to be used as feed ingredients; b) CO2 conversion and micro-nutrients capturing from microalgae to be valorized for a wide range of applications (e.g. biofuels, food and feed, fertilizers, bioactive compounds); c) CO2 transformation to biodegradable plastics precursors (e.g. Polybutylene succinate, Polyhydroxyalkanoate); d) digestate valorization for biochar production to support efficient agricultural usage. Moreover, the environmental factors and life cycle assessment perspectives of the novel biorefinery routes are revised highlighting the need for regionalized models or assessments that can reveal the most sustainable routes based on local conditions and requirements. Despite AD poses some positive characteristics related to environmental benefit and emissions reduction, the present wo

    Author(s): Panagiotis Tsapekos, Benyamin Khoshnevisan, Merlin Alvarado-Morales, Xinyu Zhu, Junting Pan, Hailin Tian, Irini Angelidaki

  • USAID DEVELOPING A SUSTAINABLE SEAFOOD INDUSTRY INFRASTRUCTURE IN MYANMAR AND ITS POTENTIAL EFFECTS ON THE COUNTRY’S ENVIRONMENTAL, ECONOMIC, AND SOCIAL SECTORS

    Sustainability is the intersection of the environmental, economic, and social sectors. A goal USAID project in Myanmar is to institutionalize sustainability in all three sectors of the seafood industry, especially the aquaculture. Myanmar is currently in a state of political, economic, and environmental turmoil, and a sustainable seafood industry and aquaculture would benefit the nation. The plan involves restoring invaluable aquatic natural resources, improving the supply chain and governance of the seafood industry, and creating stability through food security and social equity. The effects that each of these central goals of the project have on the country are guided through the principles that the GPO, a World Bank organization, uses in assessing programs with the goal of sustainability. The effects will also be confirmed through the comparison to Vietnam, a nation that has experienced a rapid growth in their aquaculture. However, because of the lack of sufficient resources placed in the environmental sector, aquaculture is experiencing problems that are affecting the economic and social sectors. This proves that not only will the desired results create sustainability in the seafood industry of Myanmar, but also demonstrates the importance of finding a balance between each of the three sectors.

    Author(s): JULIO ANTONIO ARIAS

  • USAID DEVELOPING A SUSTAINABLE SEAFOOD INDUSTRY INFRASTRUCTURE IN MYANMAR AND ITS POTENTIAL EFFECTS ON THE COUNTRY’S ENVIRONMENTAL, ECONOMIC, AND SOCIAL SECTORS

    Sustainability is the intersection of the environmental, economic, and social sectors. A goal USAID project in Myanmar is to institutionalize sustainability in all three sectors of the seafood industry, especially the aquaculture. Myanmar is currently in a state of political, economic, and environmental turmoil, and a sustainable seafood industry and aquaculture would benefit the nation. The plan involves restoring invaluable aquatic natural resources, improving the supply chain and governance of the seafood industry, and creating stability through food security and social equity. The effects that each of these central goals of the project have on the country are guided through the principles that the GPO, a World Bank organization, uses in assessing programs with the goal of sustainability. The effects will also be confirmed through the comparison to Vietnam, a nation that has experienced a rapid growth in their aquaculture. However, because of the lack of sufficient resources placed in the environmental sector, aquaculture is experiencing problems that are affecting the economic and social sectors. This proves that not only will the desired results create sustainability in the seafood industry of Myanmar, but also demonstrates the importance of finding a balance between each of the three sectors.

    Author(s): JULIO ANTONIO ARIAS

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