Primary production of intertidal temperate seagrass Zostera marina from Rimouski, QC, Canada, under a light intensity gradient

Eelgrass shoots (Zostera marina) from Rimouski, QC, were exposed in July 2020 to a natural gradient of light intensity, ranging from 6 to 860 µmol photons/m²/s, to assess the species' capacity to respond to light attenuation. After 25 days of light exposure, primary production of whole eelgrass shoots was assessed by respirometry. Net primary production (NPP), gross primary production (GPP) and dark respiration were calculated from oxygen fluxes of incubated shoots, under their respective light treatment and in total darkness, and standardized to leaf surface.