Zhangyi Xia1, Jinlin Liu1, Shuang Zhao1, Fangling Bi1, Jianheng Zhang1,2,3, Peimin He1,2,3
1College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China.
2Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China.
3Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, 10 Lianyungang 222005, China
Global warming and seawater eutrophication are resulting in unstable coastal ecology. Green tides, which have been documented in numerous seawater areas in China, have progressively become a global phenomenon. They are believed to be caused by green macroalgae shedding into the sea. The connection between algal shedding and environmental conditions has, however, barely been studied. The physiological status of algae is significantly influenced by environmental elements such as pH, sea surface temperature, and salinity. Therefore, this study assessed the correlation between the shedding rate and environmental factors (pH, sea surface temperature, and salinity) based on field observations of the shedding of attached green macroalgae in Binhai Harbor. Although there was no correlation between the shedding rate and pH, sea surface temperature, or salinity, the environmental conditions were ideal for the growth of Ulva meridionalis. The shedding rate ranged from 0.88% ± 0.11% to 4.78% ± 1.76%. Despite the fact that typhoons and currents may also have an impact on the production of the Ulva meridionalis green tides, human activities and seawater eutrophication may be the primary reasons. This study revealed Ulva meridionalis may present a new ecological threat in the Yellow Sea.