title: Near-bottom circulation and dispersion of sediment containingAlexandrium fundyensecysts in the Gulf of Maine during 2010-2011.
abstract: The life cycle ofAlexandrium fundyensein the Gulf of Maine includes a dormant cyst stage that spends the winter predominantly in the bottom sediment. Wave-current bottom stress caused by storms and tides induces resuspension of cyst-containing sediment during winter and spring. Resuspended sediment could be transported by water flow to different locations in the Gulf and the redistribution of sediment containingA. fundyensecysts could alter the spatial and temporal manifestation of its spring bloom. The present study evaluates model near-bottom flow during storms, when sediment resuspension and redistribution are most likely to occur, between October and May whenA. fundyensecells are predominantly in cyst form. Simulated water column sediment (mud) concentrations from representative locations of the Gulf are used to initialize particle tracking simulations for the period October 2010-May 2011. Particles are tracked in full three-dimensional model solutions including a sinking velocity characteristic of cyst and aggregated mud settling (0.1 mm s-1). Although most of the material was redeposited near the source areas, small percentages of total resuspended sediment from some locations in the western (~4%) and eastern (2%) Maine shelf and the Bay of Fundy (1%) traveled distances longer than 100 km before resettling. The redistribution changed seasonally and was sensitive to the prescribed sinking rate. Estimates of the amount of cysts redistributed with the sediment are small compared to the inventory of cysts in the upper few centimeters of sediment.
authors.affiliation: U.S. Geological Survey, Woods Hole, MA, USA ; Integrated Statistics, Woods Hole, MA, USA.
authors.forename: Alfredo L
authors.initials: AL
authors.lastname: Aretxabaleta
authors.affiliation: U.S. Geological Survey, Woods Hole, MA, USA.
authors.forename: Bradford
authors.initials: B
authors.lastname: Butman
authors.affiliation: U.S. Geological Survey, Woods Hole, MA, USA.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Signell
authors.affiliation: U.S. Geological Survey, Woods Hole, MA, USA.
authors.forename: P Soupy
authors.initials: PS
authors.lastname: Dalyander
authors.affiliation: U.S. Geological Survey, Woods Hole, MA, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Sherwood
authors.affiliation: University of Rhode Island, Narragansett, RI, USA.
authors.forename: Vitalii A
authors.initials: VA
authors.lastname: Sheremet
authors.affiliation: Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: McGillicuddy
keywords: Gulf of Maine; Harmful Algal Bloom cysts; Near-bottom circulation; Particle tracking; Sediment connectivity