舟山近岸海域赤潮生物与赤潮特征研究

Research on red tide organisms and red tide characteristics in the coastal waters of Zhoushan

研究赤潮生物与赤潮特性是了解赤潮成因、判断赤潮趋势和科学预防应对赤潮的有效手段和途径。对2002-2021年舟山近岸海域发生的190次赤潮进行分析,主要高发区为嵊泗、朱家尖东部和东极海域,高发期在5-7月,主要赤潮生物30种。2020-2021年对舟山近岸海域40个点位浮游植物进行调查发现,赤潮生物有58种,主要优势种有中肋骨条藻(Skeletonema costatum)、尖刺拟菱形藻(Pseudo-nitzschiapungens)、洛氏角毛藻(Chaetoceros lorenziunus)、旋链角毛藻(Chaetoceros curvisetus)、刚毛根管藻(Rhizosolenia setigera)、东海原甲藻(Prorocentrum donghaiense)等。嵊泗、朱家尖东部和东极海域夏季赤潮生物种类和丰度最高,秋季次之。近5年来,近岸海域水质总体提升,富营养指数相对稳定,为2.33~4.28,一到三类海水比例与赤潮年度累计面积呈负相关,赤潮发生频次受水文气象因素影响,夏季高发区赤潮优势种丰度较高,发生赤潮的内外因素依然存在。

Studying the organisms and characteristics of red tides is an effective means and way to understand the causes of red tides,judge the trend of red tides,and scientifically prevent and respond to red tides.This paper analyzes 190 red tides that occurred in the coastal waters of Zhoushan from 2002 to 2021,mainly in Shengsi,eastern Zhujiajian and East Polar waters,with a high incidence period from May to July,and 30 major red tide organisms.In 2020-2021,40 point phytoplankton plants were investigated in the coastal waters of Zhoushan,and there were 58 species of red tide organisms,the main dominant species were Skeletonema costatum,Pseudo-nitzschiapungens,Chaetoceros lorenziunus,Chaetoceros curvisetus,Rhizosolenia setigera,Prorocentrum donghaiense and others.Shengsi eastern Zhujiajian and East Polar waters had the highest variety and abundance of red tide organisms in summer,which was followed by autumn.In the past five years,the water quality of coastal waters was generally improved,and the eutrophic index was relatively stable in the range of 2.33~4.28;the proportion of seawater of one to three types was negatively correlated with the annual cumulative area of red tides,and the frequency of red tides was affected by hydrometeorological factors.The abundance of dominant species of red tides in summer high incidence areas was high,and internal and external factors of red tides still existed.