Disentangling the ecological processes shaping the latitudinal pattern of phytoplankton communities in the Pacific Ocean

Xu, Zhimeng and Cheung, Shunyan and Endo, Hisashi and Xia, Xiaomin and Wu, Wenxue and Chen, Bingzhang and Ho, Ngai Hei Ernest and Suzuki, Koji and Li, Meng and Liu, Hongbin (2022) Disentangling the ecological processes shaping the latitudinal pattern of phytoplankton communities in the Pacific Ocean. mSystems, 7 (1). e01203-21. ISSN 2379-5077 (https://doi.org/10.1128/msystems.01203-21)

[thumbnail of Xu-etal-mSystems-2021-Disentangling-the-ecological-processes-shaping-the-latitudinal-pattern-of-phytoplankton-communities]
Text. Filename: Xu_etal_mSystems_2021_Disentangling_the_ecological_processes_shaping_the_latitudinal_pattern_of_phytoplankton_communities.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (2MB)| Preview


Phytoplankton diversity and community compositions vary across spaces and are fundamentally affected by several deterministic (e.g., environmental selection) and stochastic (e.g., ecological drift) processes. How this suite of different processes regu- lates the biogeography of phytoplankton remains to be comprehensively explored. Using high-throughput sequencing data and null model analysis, we revealed the ecological proc- esses shaping the latitudinal community structure of three major phytoplankton groups (i.e., diatoms, Synechococcus, and haptophytes) across the Pacific Ocean (70°N, 170°W to 35°S, 170°W). At the basin scale, heterogeneous selection (selection under heterogeneous environmental conditions) dominated the assembly processes of all phytoplankton groups; however, its relative importance varied greatly at the climatic zonal scale, explaining the dis- tinct latitudinal a- and b-diversity among phytoplankton groups. Assembly processes in Synechococcus and haptophyte communities were mainly controlled by physical and nutri- ent factors, respectively. High temperature drove Synechococcus communities to be more deterministic with higher diversity, while haptophyte communities were less environmen- tally selected at low latitudes due to their wide niche breadth and mixotrophic lifestyle. Diatom communities were overwhelmingly dominated by the selection process but with low correlation of measured environmental factors to their community compositions. This could be attributed to the high growth rate of diatoms, as indicated by their lower site occupation frequency than predicted in the neutral community model. Our study showed that heterogeneous selection is the main force that shaped the biogeography of three key phytoplankton groups in the Pacific Ocean, with a latitudinal variation of relative impor- tance due to the distinct traits among phytoplankton.