Inter-Research > MEPS > v678 > p37-49  
MEPS
Marine Ecology Progress Series

via Mailchimp

MEPS 678:37-49 (2021)  -  DOI: https://doi.org/10.3354/meps13865

Effects of temperature on a mixotrophic dinoflagellate (Lepidodinium sp.) under different nutritional strategies

Kailin Liu1,#, Herrick Yin-To Ng1,#,, Shuwen Zhang2, Hongbin Liu1,3,4,*

1Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, PR China
2Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Healthy and Safe Aquaculture, School of Life Science, South China Normal University, West 55 of Zhongshan Avenue, Guangzhou 510631, PR China
3Hong Kong Branch of Southern Marine Science & Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, PR China
4State Key Laboratory of Marine Pollution, Hong Kong SAR, PR China
*Corresponding author:
#These authors contributed equally to this work

ABSTRACT: Mixotrophs are widely distributed in aquatic ecosystems and play critical roles in the planktonic food web. However, how mixotrophs respond to projected ocean warming remains a debatable topic. To close the knowledge gap, we investigated the thermal responses of growth rate and functional traits of a mixotrophic dinoflagellate (Lepidodinium sp.) isolated from subtropical coastal waters. We found that Lepidodinium sp. is a facultative mixotroph with an obligate phototrophic lifestyle that adjusts its phagocytotic feeding according to inorganic nutrient concentrations. The thermal sensitivity in terms of activation energy (Ea, eV) of Lepidodinium sp. grown in mixotrophic mode (with sufficient prey, 0.69-0.89 eV) was significantly higher than in autotrophic mode (without prey, 0.30-0.37 eV). This finding is consistent with the results of predominantly heterotrophic mixotrophs, providing experimental evidence for the hypothesis that mixotrophs shift towards more heterotrophy with rising temperatures. Warming stimulated a higher growth rate of Lepidodinium sp. grown in mixotrophic conditions than in autotrophic conditions, indicating that mixotrophic dinoflagellates may benefit substantially from mixotrophy when temperature increases and prey is sufficient. Moreover, the cell size of both autotrophic and mixotrophic Lepidodinium sp. decreased with increasing temperature. The N:P and C:P ratios of Lepidodinium sp. did not vary with temperature, while the C:N ratio slightly increased. Our results suggest that mixotrophs like Lepidodinium sp. would become more heterotrophic with higher growth rates in warming oceans. The subsequent changes in their functional role from primary producers to consumers may affect food web dynamics and carbon and nutrient cycling.


KEY WORDS: Mixotrophs · Nutrition · Temperature · Stoichiometric ratio


Full text in pdf format
Supplementary material 
Cite this article as: Liu K, Ng HY, Zhang S, Liu H (2021) Effects of temperature on a mixotrophic dinoflagellate (Lepidodinium sp.) under different nutritional strategies. Mar Ecol Prog Ser 678:37-49. https://doi.org/10.3354/meps13865

Export citation
Mail this link - Contents Mailing Lists - RSS
Facebook - - linkedIn