Relationship between bacteria and phytoplankton during the giant jellyfish Nemopilema nomurai bloom in an oligotrophic temperate marine ecosystem

• Published in: Acta oceanologica Sinica Vol. 35; no. 10; pp. 107 - 113
• Main Authors: Zeng, Yang, Huang, Xuguang, Huang, Bangqin, Mi, Tiezhu
• Format: Journal Article
• Language: English
• Published: Beijing The Chinese Society of Oceanography 01-10-2016; Springer Nature B.V; Key Laboratory of Coastal and Wetland Ecosystems of Ministry of Education, Xiamen University, Xiamen 361005, China%College of Chemistry and Chemical Engineering, 0cean University of China, Qingdao 266003, China
• Subjects: Abundance; Bacteria; Biomass; Carbon; Chlorophyll; Chlorophyll a; Climatology; Cnidaria; Community structure; Correlation; Earth and Environmental Science; Earth Sciences; Ecology; Engineering Fluid Dynamics; Environmental Chemistry; Environmental factors; Food chains; Jellyfish blooms; Marine; Marine & Freshwater Sciences; Marine ecosystems; Marine invertebrates; Mixed layer; Nemopilema nomurai; Nitrates; Nutrients; Oceanography; Offshore; Phosphates; Phytoplankton; Plankton; Primary production; Respiration; 初级生产力; 叶绿素a浓度; 巨型; 水母; 浮游植物生物量; 海洋生态系统; 细菌丰度; 贫营养; Yellow Sea; China; INW, Huanghai Sea; phytoplankton; pigments; jellyfish bloom; jellyfish DOM; ecological consequence; Nemopilema nomurai
• ISSN: 0253-505X; 1869-1099
• DOI: 10.1007/s13131-016-0894-x

Bacterial abundance, phytoplankton community structure and environmental parameters were investigated to study the relationships between bacteria and phytoplankton during giant jellyfish Nemopilema nomurai blooms in the central Yellow Sea during 2013. N. nomurai appeared in June, increased in August, reached a peak and began to degrade in September 2013. Results showed that phosphate was possible a key nutrient for both phytoplankton and bacteria in June, but it changed to nitrate in August and September. Phytoplankton composition significantly changed that pico-phytoplankton relative biomass significantly increased, whereas other size phytoplankton significantly decreased during jellyfish bloom. In June, a significantly positive correlation was observed between chlorophyll a concentration and bacterial abundance（r=0.67, P0.001, n=34）.During jellyfish outbreak in August, there was no significant correlation between phytoplankton and bacteria（r=0.11, P0.05, n=25）, but the relationship（r=0.71, P0.001, n=31） was rebuilt with jellyfish degradation in September. In August, small size phytoplankton occupied the mixed layer in offshore stations, while bacteria almost distributed evenly in vertical. Chlorophyll a concentration significantly increased from（0.42±0.056） μg/L in June to（0.74±0.174） μg/L in August, while bacterial abundance just slightly increased. Additionally, the negative net community production indicated that community respiration was not entirely determined by the local primary productivity in August. These results indicated that jellyfish blooms potentially affect coupling of phytoplankton and bacteria in marine ecosystems.