Miao Xiaoxiang, Xiao Jie, Xu Qinzeng, Fan Shiliang, Wang Zongling, Wang Xiao, Zhang Xuelei
College of Environmental Science and Engineering, Ocean University of China, Qingdao, China.
Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao, China.
PeerJ. 2020 Dec 17;8:e10538. doi: 10.7717/peerj.10538. eCollection 2020.
Massive floating green macroalgae have formed harmful green tides in the Yellow Sea since 2007. To study the early development and the associated environmental factors for the green tide, a field survey was carried out in the Subei Shoal, southwestern Yellow Sea. Multiple species were identified in both floating green macroalgae and micro-propagules , while their abundances showed distinct spatial variations. The floating macroalgal biomass was widespread in the northern Subei Shoal and most abundant at 34°N. dominated (91.2% in average) the floating macroalgae, and the majority (88.5%) of was the 'floating type'. In comparison, the micro-propagules were most abundant around the aquaculture rafts, and decreased significantly with the distance to the rafts. The dominant species of micro-propagules was (48.5%), followed by (35.1%). Their distinct distribution patterns and species diversity suggested little direct contribution of micro-propagules for the floating macroalgae. The spatial variation of the floating macroalgae was probably a combined result from the biomass source and environmental factors, while the abundance of micro-propagules was closely associated with the rafts. A positive correlation between the floating macroalgae and DO was observed and suggested active photosynthesis of the initial biomass in Subei Shoal. This study revealed specific distributional pattern and relationships among the floating macroalgae, micro-propagules and the environmental factors in the source region, which helps understanding the early blooming dynamics of the green tides in Yellow Sea.
自2007年以来，大量漂浮的绿色大型海藻在黄海形成了有害绿潮。为了研究绿潮的早期发育及相关环境因素，在黄海西南部的苏北浅滩进行了实地调查。在漂浮的绿色大型海藻和微型繁殖体中均鉴定出多个物种，但其丰度呈现出明显的空间变化。漂浮大型海藻生物量在苏北浅滩北部广泛分布，在北纬34°处最为丰富。 在漂浮大型海藻中占主导地位（平均占91.2%），且大部分（88.5%）的 为“漂浮型”。相比之下，微型繁殖体在养殖筏周围最为丰富，并随着与筏的距离增加而显著减少。微型繁殖体的优势种为 （48.5%），其次是 （35.1%）。它们不同的分布模式和物种多样性表明微型繁殖体对漂浮大型海藻的直接贡献很小。漂浮大型海藻的空间变化可能是生物量来源和环境因素共同作用的结果，而微型繁殖体的丰度与养殖筏密切相关。观察到漂浮大型海藻与溶解氧之间呈正相关，这表明苏北浅滩初始生物量的光合作用活跃。本研究揭示了源区漂浮大型海藻、微型繁殖体与环境因素之间的特定分布模式和关系，有助于理解黄海绿潮的早期爆发动态。
