Potential Effects of Some Environmental Factors on a Dinoflagellate Red Tide Caused by Gymnodinium catenatum in Shenhu Bay in 2017

• 作者: Chen Jingwu Li Guangyi Liu Baoqing Yang Fan Yao Rui Zheng Chongrong
• 来源期刊: 气象与环境研究:英文版
• 学科: 地球科学
• 关键词: Shenhu Bay COASTAL WATERS Red TIDE GYMNODINIUM catenatum Environmental factors
• 年，卷（期）: 2019,（4）
• 页码范围: 26-30
• 页数: 5页
• 分类号: P

摘要

In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The highest cell density of G. catenatum was 1.0×10 6 cells/L, so it was known as the predominant species of the red tide discovered in Fujian coastal waters for the first time. Continuous rainfall process brought many land-based pollutants into the coastal waters, providing abundant nutrients for plankton growth. Then the continuous sunny and hot weather, high temperature, high salinity and south wind conditions accelerated the formation and occurrence of the red tide. During the red tide, DO, pH and COD increased remarkably and had significant positive correlations with the cell density of the red tide organisms. The contents of various nutrients decreased obviously, and eutrophication index E became low before and after the red tide, indicating the oligotrophic status of Shenhu Bay coastal waters. It is also found that DIP was one of the determinant environmental factors that induced the red tide. The N/P ratio of water in the declining phase of the red tide was close to the Redfield ratio. As for DIN, NH + 4-N and NO - 3-N were the two main species of inorganic nitrogen needed for this red tide dinoflagellate. The study indicates the relationship between the occurrence of the red tide and environmental conditions, providing essential reference for monitoring and forecasting research of red tide in marine environment and ecosystem management.