Formulation of a new footprint model for measuring fluxes of biological
resuspension
- Uri Shavit,
- Nir Marom,
- Roi Holzman,
- Emmanuel Boss,
- Timor Katz,
- Gitai Yahel
Nir Marom
Civil and Environmental Engineering, Technion, Haifa, Israel
Author ProfileRoi Holzman
School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel
Author ProfileEmmanuel Boss
School of Marine Sciences, University of Maine, Orono, ME 04469, USA
Author ProfileTimor Katz
Israel Oceanographic & Limnological Research, Tel Shikmona, 31080 Haifa, Israel
Author ProfileGitai Yahel
The Faculty of Marine Sciences, Ruppin Academic Center, Michmoret, Israel
Author ProfileAbstract
Biological resuspension of sediments from the seafloor occurs when fish
and other marine creatures search for food and shelter. In high-energy
habitats, waves and currents dominate the resuspension of sediments,
however, studies suggest that biological resuspension is the dominant
process in areas below the wave action including the deep sea and in low
energy zones such as lagoons and other sheltered basins. Biological
resuspension is a highly punctuated process both in time and space,
generating high concentration sediment plumes that quickly sink and
disperse. It is therefore not surprising that despite its potentially
large impact, no quantitative data exists regarding its extent and
ecological impact in the ocean. To resolve the difficulty in monitoring
and quantifying these short-live resuspension events, we develop a model
named the footprint model that converts field measurements of horizontal
sediment fluxes, into estimates of long-term average fluxes of
biological resuspension. Measurements of the horizontal fluxes of the
suspended sediments by off-the-shelf instruments serve as an input to
the footprint model, which are then analyzed by the algebraic equations
of the model. Given a horizontal velocity profile, the model quantifies
the sedimentation of heavy particles as a function of their size,
initial distribution and advection. Flow measurements are then used to
include the effect of dispersion by the turbulent flow. The document
provides a detailed description of the model derivation and proposes
techniques that can be used for validation of the model results.