title: Dynamics of two picophytoplankton groups in mediterranean sea: analysis of the deep chlorophyll maximum by a stochastic advection-reaction-diffusion model.
abstract: A stochastic advection-reaction-diffusion model with terms of multiplicative white Gaussian noise, valid for weakly mixed waters, is studied to obtain the vertical stationary spatial distributions of two groups of picophytoplankton, i.e., picoeukaryotes and Prochlorococcus, which account about for 60% of total chlorophyll on average in Mediterranean Sea. By numerically solving the equations of the model, we analyze the one-dimensional spatio-temporal dynamics of the total picophytoplankton biomass and nutrient concentration along the water column at different depths. In particular, we integrate the equations over a time interval long enough, obtaining the steady spatial distributions for the cell concentrations of the two picophytoplankton groups. The results are converted into chlorophyll a and divinil chlorophyll a concentrations and compared with experimental data collected in two different sites of the Sicily Channel (southern Mediterranean Sea). The comparison shows that real distributions are well reproduced by theoretical profiles. Specifically, position, shape and magnitude of the theoretical deep chlorophyll maximum exhibit a good agreement with the experimental values.
authors.affiliation: Dipartimento di Fisica e Chimica, Università di Palermo, Group of Interdisciplinary Physics and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Unità di Palermo, Palermo, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Denaro
authors.forename: Davide
authors.initials: D
authors.lastname: Valenti
authors.forename: Bernardo
authors.initials: B
authors.lastname: Spagnolo
authors.forename: Gualtiero
authors.initials: G
authors.lastname: Basilone
authors.forename: Salvatore
authors.initials: S
authors.lastname: Mazzola
authors.forename: Salem W
authors.initials: SW
authors.lastname: Zgozi
authors.forename: Salvatore
authors.initials: S
authors.lastname: Aronica
authors.forename: Angelo
authors.initials: A
authors.lastname: Bonanno
mesh_terms: D002734:Chlorophyll / Q000378:metabolism*; D008522:Mediterranean Sea; D008962:Models, Theoretical; D010839:Phytoplankton / Q000378:metabolism*
chemical_list: D002734:Chlorophyll