Floating seaweeds may complete their partial or whole life cycle in floating state.The number of green and golden tides caused by floating macroalgae has been continuously increasing.In 2008,the largest green tide ever recorded happened in Yellow Sea.Besides,macroalgal bloom caused by Sargassum horneri occurred in the coastal areas of China regularly,which has caused considerable damage to the local environment and economy.Floating seaweeds have a high photosynthetic rate and photoprotective capacity of acclimating and adapting to the sea surface conditions;they can reproduce rapidly and grow fast.In this review,we summarized the researches on floating seaweeds,and discussed their photosynthetic characteristics and high-light adaption mechanisms.Floating seaweeds have a high photosynthetic activity,but a low photosynthetic potential.Floating seaweeds have efficient carbon fixation in surface seawater.They also have a variety photoprotective mechanisms including reducing light absorption and increasing thermal dissipation
