Factors influencing the spatial and temporal distributions of green algae micro-propagules in the coastal waters of Jinmenghaiwan, Qinhuangdao, China

Abstract

Since 2015, green tides have impacted the coastal waters of Qinhuangdao, particularly at Jinmenghaiwan bath. Micro-propagules are considered the “seed bank” of algal blooms and play an important role in the formation of green tides. To investigate the spatial and temporal distributions of micro-propagules of green algae and associated environmental factors, a field survey was carried out in the coastal waters of Jinmenghaiwan, Qinhuangdao, China. The results showed that the NO3-N concentration was the most important impact factor of the abundance of micro-propagules and explained 42.9% of the total variance. Furthermore, the number of micro-propagules was significantly and positively correlated with the biomass of attached and floating macroalgae. Therefore, reducing the NO3-N concentration by controlling the NO3-N input from Tang River is expected to be an effective measure to prevent and control green tides in the coastal waters of Qinhuangdao.