秦皇岛绿潮暴发区微观繁殖体的时空分布特征及影响因素

Spatio-Temporal Distribution and Impact Factors of Green Macroalgal Micro-Propagules in the Coastal Waters of Qinhuangdao

2015年至今,秦皇岛近岸海域连年发生绿潮灾害,造成严重社会影响和经济损失。微观繁殖体作为绿潮藻的种源,在绿潮的发生过程中起着十分重要的作用。为此,于2020年5月至9月对秦皇岛绿潮暴发较为严重的金梦海湾海域(119°32′54″~119°33′00″E,39°52′45″~39°53′30″N)进行采样调查,分析了绿潮暴发区水体和沉积物中微观繁殖体的时空特征、种类组成及主要影响因素。结果表明:秦皇岛绿潮暴发区和邻近海域水体,以及沉积物中绿藻微观繁殖体丰度均在6月较高,在7月和8月较低;绿潮影响区微观繁殖体丰度高于非影响区;0~5 cm表层沉积物的微观繁殖体丰度远高于5 cm及以深的沉积物;水体与沉积物中的微观繁殖体分布特征与海域海藻生物量和环境因子密切相关,两者丰度与绿潮发生区悬浮海藻和海藻场定生海藻的生物量呈显著的正相关关系;微观繁殖体丰度与温度、盐度呈负相关关系,与可溶性无机氮呈正相关关系。该研究将为进一步阐明秦皇岛绿潮发生的关键过程及防灾减灾提供支撑。

Green tides have continuously occurred in the coastal waters of Qinhuangdao since 2015.It has caused serious social and economic impacts.Micro-propagules,the seeds of macroalgae,play an important role in maintaining the populations of large-scale green algae.Here,the distribution and species composition of micro-propagules in the water and sediment were investigated in the Jinmeng Bay from May to September 2020.The results showed that the abundance of micro-propagules was greater in June than that in July and August,and the higher abundance of micro-propagules was distributed in the more macroalgae suspending areas.The abundance of micro-propagules decreased sharply in the sediment deeper than 5 cm.The distribution of micro-propagules in the water and sediment was positively correlated with the biomass of suspended macroalgae and attached macroalgae in the seaweed beds.The abundance of the micro-propagules had negative correlation with temperature and salinity,while it was positively correlated with dissolved inorganic nitrogen.This study can provide supports for further clarifying the key processes of green tide in Qinhuangdao.