Estimates of cell biovolume and carbon of protistan plankton taxa from inshore waters of the United Kingdom

This datasets describes the estimated values of biovolume and carbon mass per cell of inshore, single-celled autotrophic, mixotrophic and heterotrophic plankton, based on combined datasets from Plymouth Marine Laboratory and the Environment Agency. It contains 644 rows in total, each with a taxon-specific determination of mean cell volume and carbon per cell. This is based on two component datasets from the Plymouth Marine Laboratory’s L4 monitoring site 6 miles south of Plymouth and Phytoplankton monitoring data review from the Environment Agency’s (and predecessor organizations) inshore UK waters sampling program. Both are based on Lugol’s-preserved settled water samples (and separate formalin-preserved samples for L4 coccolithophores), enumerated by light microscopy. It includes determinations for diatoms, dinoflagellates, ciliates, coccolithophores, flagellates and various other single-celled eukaryotic plankton. The two datasets provide independent estimates of cell biovolume, from which the commonly-used conversion factors of Menden-Deuer and Lessard (2000) have been used to further estimate carbon. We stress that both the size and the elemental content of protists is highly variable, and we assessed the congruence of the two datasets for 98 of the taxa that were common to both. Determinations for diatoms agreed well, whereas those for the intermediate size (i.e. 100-10,000 pg C) non-diatom did not, with PML values often over an order of magnitude greater than those from the EA. This spreadsheet gives a first approximation of the sizes and carbon contents of over 600 UK taxa, but users of the data need to be aware of uncertainties in these estimates, both of size and of body composition of these highly variable cells. Please use the data citation above when using these data.