Sensitivity of Chlorophyll a fluorometers was assessed during a mesocosm experiment
The sensitivity of contemporary field sensors in measuring phytoplankton fluorescence was tested and compared in the Cretan Sea. These tests, contributing to MINKE WP9, were performed during a mesocosm experiment, jointly organised by INFRAIA projects AQUACOSM-plus and JERICO-S3. In this 10-day experiment, in May-June 2022, natural coastal seawater was enriched with airborne aerosols and microbes, as well as dust from Sahara desert. Phytoplankton biomass remained very low throughout the experiment and non-photochemical fluorescence quenching was very high due to intense sunlight, thus conditions which are very challenging for field fluorometers. Fluorometers from three manufacturers were compared and will be further validated against laboratory analysis of phytoplankton pigments. The results will guide the selection of sensors to be used in such oligotrophic conditions and assists MINKE in its further efforts towards traceable calibration of field fluorometers. Study involved MINKE partners SYKE, HCMR and NIVA.
Figure 1: Mesocosm facility at HCMR
Figure 2. Preparing a frame for sensors
Links to JERICO and AQUACOSM webpages