Pigment characterization for the 2011 bloom in Qinhuangdao implicated "brown tide" events in China

A large-scale bloom occurred from May to June in 2011 in sea area near Qinhuangdao of the Bohai Sea, leading to huge damage of the scallop culture industry. Similar blooms have been observed in this region for three years. The causative species of the bloom, which dominated the phytoplankton community with the maximum cell density around 109 cell/L, could not be identified with morphological features due to the small cell size （-2 μm）. A pigment analytical method was then adopted to analyze the pigment profile of the phytoplankton samples collected from the blooming sea area. It was found that pico-sized （〈2 μm）, nano-sized （2-20 μm）, and bulk phytoplankton samples had similar pigment profile, representing the pigment signature of the bloom-causative species. The major pigments detected included 19-butanoyloxyfucoxanthin （But-fuco）, fucoxanthin （Fuco）, diadinoxanthin （Diad） and chlorophyll a （Chl a）, and high content of But-fuco was the most significant characteristics of the phytoplankton samples. Based on the pigment composition and content, the bloom-causative species could be tentatively identified as pelagophyte, ＂type 8＂ group of haptophyte, or silicoflagellate. Some unique features of the bloom, such as the extremely high cell density, small-sized and But-fuco containing cells, occurring in early summer, and the feeding-cessation effects on scallops, suggest it be a ＂brown tide＂ event similar to those reported in the east coast of the United States of America. The recurrent ＂brown tide＂ events and their dramatic impacts on the shellfish mariculture industry in QirLhuangdao need close attention in the coming years.

一个大规模花蕾在 Bohai 海的 Qinhuangdao 附近在海区域在 2011 从 5 月发生了到 6 月，导致扇贝文化工业的巨大的损坏。类似的花蕾在这个区域被观察三年了。花蕾的原因的种，在 109 cell/L 附近与最大的细胞密度统治了浮游植物社区，不能由于小细胞尺寸(2 m m ) 与词法特征被识别。分析方法当时是的颜料采用了分析从开花的海区域收集的浮游植物样品的颜料侧面。它被发现那微微大小(< 2 m m ) ，缩放 nano (220 m m ) ，并且体积浮游植物样品有类似的颜料侧面，代表花蕾原因的种类的颜料签名。检测的主要颜料包括了 19-butanoyloxyfucoxanthin (But-fuco ) ， fucoxanthin (Fuco ) ， diadinoxanthin (二重) 并且叶绿素一(Chl 一) ，并且 But-fuco 的高内容是浮游植物样品的最重要的特征。基于颜料作文和内容，花蕾原因的种类能尝试性地作为 pelagophyte 被识别，打 8 组 haptophyte，或 silicoflagellate。花蕾的一些唯一的特征例如极其高的房间密度，小型并且 But-fuco 包含房间，发生在早夏天，和喂停止在扇贝上完成，建议它类似于那些的一个棕色的潮事件在美国的东方海岸被报导。在 Qinhuangdao 的贝壳海洋生物养殖工业上的周期性的棕色的潮事件和他们的戏剧的影响需要在来年里关上注意。