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Intensive mariculture is the predominant activity in bays or in coastal lagoons today. Inorganic and organic waste from farming activities would result in nutrient enrichment of water. The high nutritional status changes the characteristics of the ecosystem and causes a series of ecological events, including red tides, green tides and other disasters. Therefore, new mariculture systems are needed, and systems that use multiple species with disparate ecological niches can reduce wastes and costs while enhancing aquaculture benefits in terms of both productivity and environmental value. To deal with the eutrophication and consequent biological disasters resulting from mariculture in sea areas, integrated multi-trophic aquaculture (IMTA) is increasingly popular as it can remove pollutants and increase the potential economic value. In this book, we reported our practices on the nutrient bioextraction using seaweed co-cultivated in mariculture sea areas in the Hangzhou bay, Sansha bay and Xiangshan bay in China. The results could provide references for the effective control of eutrophication and the consequent ecological events.

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Yuanzi Huo-Associate Professor, College of Marine Ecology and Environment, Shanghai Ocean University, China; Visiting Scholar, University of Connecticut, USA; PhD, Institute of Oceanology, Chinese Academy of Sciences, China; B.S., Dalian Ocean University, China; Elected into member of 27th and 29th Chinese Antarctic Research Expedition.

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