Functional Trait Database describing micro-phytoplankton diversity from the North-West French coast

The primary producers represent an essential link for the ecosystem functioning. Understanding the community structure through long-term monitoring is key to understand the impact of climate and environmental changes at both global and local scale. To better understand those communities, many national and international networks have been collecting samples for the study of micro-phytoplankton (20µm to 200µm) diversity. This correspond to larger organisms among phytoplankton that can be accessed through light microscopy. However, it is hard or impossible to access pico or nano-phytoplankton through microscopy only. Looking at functional group distribution and variations with microphytoplankton data could provide information on overall primary producers’ adaptation to climate change. For instance, modification on large and small cells ratio could impact coastal ecosystem functioning and affect zooplankton, larvae and shellfish of ecological or economical interest. The phytoplankton diversity is widely explored through a taxonomical approach. Nevertheless, a more global approach that could enable to examine primary producers not through taxonomy but functional diversity – through their direct adaptation to environment variables – could provide insights into how phytoplankton community respond to environmental changes and better apprehend global effect on the ecosystem functioning. Records of the coastal micro-phytoplankton diversity are available at a national scale thanks to the REPHY (REPHY – French Observation And Monitoring Program For Phytoplankton And Hydrology In Coastal Waters, 2021). Here, we present a trait database of micro-phytoplankton entities as seen through the monitoring program for the North-West of France (Lefran et al., 2022). It has been built for the purpose of studying the impacts of environmental changes in the Eastern English Channel through a functional approach. It contains description of 93 entities through morphological, physiological and behavioural traits. The initial work of Ramond and collaborators (2018) enabled to gather most of the information contained in this database. Morphological traits were each revised with nordicmicroalgae.org to better correspond to organisms from the North-East Atlantic (by opposition to measures taken from tropical organisms). Indeed, size can vary a lot depending on the organism’s stage of life (diatoms) or its environment. Gaps and additional traits were filled through an extensive literature review. The excel file is composed of 2 tabs: · The first tab contains the datatable with all relevant information as described in the table below. Certain boxes have a comment tag indicating the reference associated to the trait, especially when the trait was not found in the main literature sources or did not correspond to local observations and required further research. This tab can be converted in a csv file to be used for functional analysis. · The second tab lists the sources used to complete the table. Books and websites with large records on phytoplankton traits are listed above, followed by species specific literature information. Column name Description Trait.s Taxon Taxonomical denomination as referred to in the REPHY program Shortname Short denomination used in analysis Rank Organism’s rank Class.worms2019 Organism’s class as registered in WoRMS 2019 (www.marinespecies.org) Ramond_nameref Taxonomical denomination as referred to in (Ramond et al., 2018) Size_min Size_max Length (µm) of the cells (minimum and maximum values estimation) from NordicMicroalgae.org Numerical Biovolume_min Biovolume_max Biovolume (µm3) of the cells (minimum and maximum values calculation based on the geometric shape) from nordicmicroalgae.org Numerical Surface_min Surface_max Surface (µm2) area of the cells (minimum and maximum values calculation based on the geometric shape) from nordicmicroalgae.org Numerical S/V_min S/V_max S/V_mean Surface / Volume ratio (µm-1) Numerical Geometric_shape Geometric shape approximation that best describe the cell morphological aspect from nordicmicroalgae.org 13 traits such as cylinder sphere, prism, cone etc… Spine_or_Setae_presence Presence of hard spines or soft setae around the cells Spines Setae None Cover Structure composition of the external cover of cells Siliceous Organic Naked Shape Binomial shape description of the cells Round Elongated Colony Cells’ capacity to form colonies and their final aspect (long straight lines or curved; ball/mass aspect) Curved Straight None Motility Capability to induce movement Floater Swimmer Glider Diet How does the organism collect or produce its energy? Autotrophic Mixotrophic Heterotrophic Habitat Water column position preferences Planktonic Tychoplanktonic (bentho-planktonic cycle) Benthic Epiphytic Harmful Harmful potential description if any None Toxin producer Fish Mortality Physical Anoxia Slime Discoloration RestingStage Resting stage / cyst form known to the organism 0 - no 1 - yes Substance producer HABs category No Toxic Harmful Credits: This trait table has been created as part of the S3-Eurohab project (https://www.s3eurohab.eu). It has been reviewed with members of the REPHY program. We recognise that nordicmicroagale.org has been a vital source of information for the study of morpho-functional traits. This database would not be as thorough without the information they openly share. The morphological information is accurate to this date (2024) but could be subject to change with new research findings. References: Lefran, A., Françoise, S., Legendre, A., Hebert, P., Hernandez-Fariñas, T., Claquin, P., 2022. Dataset of micro-phytoplankton biodiversity in the Eastern Channel area from 1987 to 2019. https://doi.org/10.5281/zenodo.7496602 Ramond, P., Siano, R., Sourisseau, M., 2018. Functional traits of marine protists. https://doi.org/10.17882/51662 REPHY – French Observation And Monitoring Program For Phytoplankton And Hydrology In Coastal Waters, ., 2021. REPHY dataset - French Observation and Monitoring program for Phytoplankton and Hydrology in coastal waters. Metropolitan data. https://doi.org/10.17882/47248