Trait-based approach revealed the seasonal variation of mesozooplankton functional groups in the South Yellow Sea

Zhishuang Zhang; Hongju Chen; Yixuan Li; Ruping Ge; Guangxing Liu; Shaukat Ali; Yunyun Zhuang

doi:10.1007/s42995-022-00156-9

Trait-based approach revealed the seasonal variation of mesozooplankton functional groups in the South Yellow Sea

Mar Life Sci Technol. 2023 Feb 13;5(1):126-140. doi: 10.1007/s42995-022-00156-9. eCollection 2023 Feb.

Authors

Zhishuang Zhang^#¹, Hongju Chen^#^{1

2}, Yixuan Li¹, Ruping Ge¹, Guangxing Liu^{1

2}, Shaukat Ali³, Yunyun Zhuang^{1

2}

Affiliations

¹ Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100 China.
² Marine Ecology and Environmental Science Laboratory, Pilot National Laboratory for Marine Science and Technology, Qingdao, 266200 China.
³ Department of Environmental Sciences, Karakoram International University, Gilgit, 15100 Pakistan.

^# Contributed equally.

Abstract

Functional traits determine the fitness of organisms and mirror their ecological functions. Although trait-based approaches provide ecological insights, it is underexploited for marine zooplankton, particularly with respect to seasonal variation. Here, based on four major functional traits, including body length, feeding type, trophic group, and reproduction mode, we quantified the seasonal variations of mesozooplankton functional groups in the South Yellow Sea (SYS) in the spring, summer, and autumn of 2018. Strong seasonal dynamics were identified for all traits but patterns varied among traits. Small zooplankton (47.7-88.6%), omnivores-herbivores (81.3-97.6%), and free spawners (54.8-92.5%) dominated in three seasons, while ambush feeders and current feeders dominated in spring (45.7%), and autumn (73.4%), respectively. Cluster analysis of the functional traits showed that the mesozooplankton in the SYS can be classified into eight functional groups. The biogeographic and seasonal variations of functional groups can be partially explained by environmental drivers. Group 1, represented by omnivores-herbivores, was the most dominant functional group, the abundance of which peaked in spring and was positively correlated with chlorophyll a concentration, indicating its close association with phytoplankton dynamics. The contribution of giant, active ambush carnivores, passive ambush carnivore jellyfish, current omnivores-detritivores, and parthenogenetic cladocerans increased with sea surface temperature. The proportion of giant, active ambush carnivores and active ambush omnivore-carnivore copepods decreased with salinity in autumn. This study presents a new perspective for understanding the dynamics of zooplankton and paves the way for further research on the functional diversity of zooplankton in the SYS.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-022-00156-9.

Keywords: Functional group; Functional trait; Seasonal variation; Southern Yellow Sea; Zooplankton.