Short-term and small-scale variability in planktic foraminifera test flux in the Bay of Biscay

Abstract

Test fluxes of planktic foraminifera in the Bay of Biscay were sampled in spring using drifting sediment traps deployed at 200m depth. At a temporal and spatial resolution of 3h and approximately 1km the foraminifer flux varied with a factor of 5. The consecutive deployments within the same area, at distances of ∼50km differed significantly in flux and relative species abundances. Flux sequences of the total foraminifer assemblage and individual species were significantly autocorrelated. The significance of autocorrelation analyses was affected by sample size of the flux sequences and limited to flux sequences with large fluxes. Autocorrelation in planktic foraminifer fluxes and standing stocks was restricted to distances <2km, and were not attributed to the temporal domain.