A novel method to simulate the 3D chlorophyll distribution in marine oligotrophic waters

A 3D advection-diffusion-reaction model is proposed to investigate the abundance of phy-toplankton in a difficult-to-access ecosystem such as the Gulf of Sirte (southern Mediter-ranean Sea) characterized by oligotrophic waters. The model exploits experimentally mea-sured environmental variables to reproduce the dynamics of four populations that dom-inate phytoplankton community in the studied area: Synechococcus, Prochlorococcus HL, Prochlorococcus LL and picoeukaryotes. The theoretical results obtained for phytoplankton abundances are converted into chl-a and Dvchl-a concentrations, and the simulated vertical chlorophyll profiles are compared to the corresponding experimentally acquired data dur -ing the MedSudMed-08 oceanographic survey. Non parametric tests showed that the 3D model successfully simulates the spatial distribution of chlorophyll in most of the Gulf of Sirte. Statistical analysis indicates that about 80% of the simulated chlorophyll vertical pro-files are not significantly different from the experimental data. This model is also a useful tool to predict chlorophyll distributions in hard-to-access areas, where experimental data cannot be collected. Moreover, the model could be used to predict the effects of global warming on phytoplankton dynamics and primary production in marine ecosystems (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study proposed a 3D model that successfully simulated the spatial distribution of chlorophyll in most parts of the Gulf of Sirte, with 80% of the simulated results matching the experimental data. This model can be used to predict chlorophyll distributions in hard-to-access areas and to forecast the impact of global warming on phytoplankton in marine ecosystems.