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To discover the original source and clarify development of the world's largest transregional green tides in the Yellow Sea, an integrated investigation covering the Subei Shoal coastal waters and the adjacent regions was carried out during March to June of 2012. The results showed that macroalgal wastes from the connecting ropes of Porphyra aquaculture rafts contributed significantly to the original biomass of free-floating green algae. Approximately 6500 t of Ulva prolifera were released into the coastal waters from mid-April to late-May when farmers were cleaning aquaculture facilities. Among the total biomass disposed, about 62.3% floated up to the sea surface, which turned into the original floating patches. The floating U. prolifera, with a high growth rate of 26.3% per day, dominated in the floating algal patches rapidly, moved northward under the hydrodynamic action, and formed a massive free-floating green tide near the south of Shandong peninsula in early June. The optimal sea temperature and sufficient nutrients in the Yellow Sea facilitated the formation of the green tide. No other source contributing substantially to the initial floating biomass was detected in the survey except those from the connecting ropes of rafts. Based on our field data, we concluded that the green tide in Yellow Sea is a transregional disaster stimulated directly by the unhygienic husbandry and maintenance practices of coastal aquaculture.

The Ulva prolifera green tides in the Yellow Sea, China, which have been occurring since 2007, are a serious environmental problem attracting worldwide attention. Despite extensive research, the outbreak mechanisms have not been fully understood. Comprehensive analysis of anthropogenic and natural biotic and abiotic factors reveals that human activities, regional physicochemical conditions and algal physiological characteristics as well as ocean warming and biological interactions (with microorganism or other macroalgae) are closely related to the occurrence of green tides. Dynamics of these factors and their interactions could explain why green tides suddenly occurred in 2007 and decreased abruptly in 2017. Moreover, the consequence of green tides is serious. The decay of macroalgal biomass could result in hypoxia and acidification, possibly induce red tide and even have a long-lasting impact on coastal carbon cycles and the ecosystem. Accordingly, corresponding countermeasures have been proposed in our study for future reference in ecosystem management strategies and sustainable development policy.

The CF(3) radical was generated from the reaction of S-(trifluoromethyl)diphenylsulfonium triflate with Na(2)S(2)O(4) or HOCH(2)SO(2)Na under suitable conditions without further reduction. Based on this, a method for the synthesis of α-trifluoromethylated ketones has been successfully developed.