We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Assessing the spatial and temporal variability of MeHg biogeochemistry and bioaccumulation in the Mediterranean Sea with a coupled 3D model.
- Authors
Rosati, Ginevra; Canu, Donata; Lazzari, Paolo; Solidoro, Cosimo
- Abstract
Human exposure to mercury (Hg) is a cause of concern, due to the biomagnification of the neurotoxic species monomethylmercury (MMHg) in marine ecosystems. Previous research revealed that commercial fish species in the Mediterranean Sea ecosystems are particularly enriched in Hg, due to a combination of physical and ecological factors. Since the fate of Hg depends on the interactions among several biogeochemical and physical drivers, biogeochemical modelling is crucial to support the integration and interpretation of field data. Here, we develop and apply a coupled transportbiogeochemical-metal bioaccumulation numerical model (OGSTM-BFM-Hg), to simulate the biogeochemical cycling of the main Hg species (HgII, Hg0, MMHg, and DMHg) in seawater, organic detritus, and through the planktonic food web. The model is applied to a 3D domain of the Mediterranean Sea to investigate the spatial and temporal variability of MeHg distribution and bioaccumulation. Model results reproduce the strong vertical and zonal gradients of MeHg concentrations related to primary production consistently with the observations, and highlight the role of winter deep convection and summer water stratification in shaping the MeHg vertical distribution, including sub-surface MeHg maximum. The modelled bioaccumulation dynamics in plankton food webs are characterized by a high spatial and temporal variability that is driven by plankton phenology, and are in agreement with available field data of concentrations in plankton and with other indicators, such as bioconcentration factors (BCFs) and trophic magnification factors (TMFs). Model results pointed out that the increment in water temperature linked to a decline of deep convection can cause an increase in water MeHg concentrations with cascading effects on plankton exposure and bioaccumulation.
- Subjects
BIOACCUMULATION; BIOGEOCHEMISTRY; BIOGEOCHEMICAL cycles; BIOMAGNIFICATION; FOOD chains; PLANT phenology
- Publication
Biogeosciences Discussions, 2022, p1
- ISSN
1810-6277
- Publication type
Article
- DOI
10.5194/bg-2022-14