Abstract
Quantifying phytoplankton composition is critical to predicting marine ecosystem structure and function. DNA meta-barcoding and high-performance liquid chromatography (HPLC) pigment analysis are two widely used methods for assessing phytoplankton composition; however, comparing their performance has been done only rarely. Here, we integrate DNA meta-barcoding and HPLC pigment observations to determine eukaryotic phytoplankton composition in the Santa Barbara Channel, California. We find that both methods identify the same four dominant eukaryotic phytoplankton taxa (diatoms, dinoflagellates, chlorophytes, and prymnesiophytes), but inter- and intra-lineage variability in biomarker pigmentation (associated with both a lack of taxonomic specificity of biomarker pigments and intrinsic differences in accessory pigmentation) drives substantial disagreement between the methods. Covariation network analysis circumvents this disagreement and reveals that diverse assemblages of phytoplankton and other protists covary with distinct suites of biomarker pigments. Our results highlight the strengths and weaknesses of each method in characterizing phytoplankton composition and reveal novel insights into phytoplankton physiology that could only be gained by integrating the two methods. Finally, we suggest a path to monitor eukaryotic plankton communities on unprecedented spatiotemporal scales based on the covariation of unique phytoplankton and protistan assemblages with remotely sensible phytoplankton pigment concentrations.
| Original language | English |
|---|---|
| Pages (from-to) | 361-376 |
| Number of pages | 16 |
| Journal | Limnology and Oceanography |
| Volume | 68 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 2023 |
Funding
The authors thank the Plumes and Blooms team, especially Nathalie Guillocheau and Stuart Halewood, for their efforts collecting the data and samples analyzed here. The authors also thank Jeff Krause for sharing the DNA meta‐barcoding samples analyzed here, and Tom Bell for sharing curated photosynthetically available radiation data. Plumes and Blooms is funded by the National Aeronautics and Space Administration (NASA; 80NSSC18K0735; 80NSSC21K1750), and ship time for the data presented here was provided by NASA and the National Oceanic and Atmospheric Administration (NOAA) Channel Islands National Marine Sanctuary. Additional support of this work and of D.C. was provided by the NASA Biodiversity and Ecological Forecasting program (Grant NNX14AR62A), the Bureau of Ocean and Energy Management Ecosystem Studies program (BOEM award MC15AC00006) and NOAA in support of the Santa Barbara Channel Marine Biodiversity Observation Network, and by the NASA PACE Science Team (Grant 80NSSC20M0226). D.C. was also funded in part by a NASA Earth and Space Science Fellowship (Grant NNX16AO44HS02). Meta‐barcoding samples were collected under the NASA Earth and Space Science Fellowship Program (Grant NNX12AO13H to E.K.W.) and National Science Foundation Award OCE‐0850857 to C.A.C.