Impacts of storms on Recent planktic foraminiferal test production and CaCO3 flux in the North Atlantic at 47 °N, 20 °W (JGOFS)

https://doi.org/10.1016/0377-8398(95)00035-6Get rights and content

Abstract

Planktic foraminiferal assemblages are well known to vary in accordance with seasonal fluctuations in ocean properties, periodic reproduction cycles, and variations between water masses. Here we report that storms also can significantly influence foraminiferal assemblages. During the RV Meteor cruise 21 to the Northeast Atlantic Ocean (biotrans area), from March to May 1992, planktic foraminifera were sampled using a multiple opening-closing net. While sampling, two storms with wind forces up to 12 Beaufort caused intensified surface layer mixing with shifts in the depth of the upper ocean mixed-layer from 20–40 m to 170–240 m. Subsequently, planktic foraminiferal growth rates increased, resulting in an elevated quantity of small (100–150 μm) tests (Phase 1). When the wind strength increased a second time, the mixed-layer deepened to a depth below the former position of the pycnocline, and again the abundance of small tests increased (Phase 2). During Phase 2, the weight of calcite in specimens of the productive zone reached its maximum. In the export zone, an associated increase in empty tests occurred with a lag time depending on the test sinking velocity. In the upper export zone, down to 700 m water depth, CaCO3 flux increased from 9.3 to 49.8 mg CaCO3 m−2 d−1 after the first storm and from 8.9 to 19.9 mg CaCO3 m−2d−1 after the second storm. In the 700 to 2500 m depth interval, the flux increased from 5.1 mg CaCO3 m−2 d−1 to about 9.2 mg CaCO, m−2 d−1. Thus, the standing stock of living foraminifera and export of empty tests from the productive zone increased after the storms, leading to pulses of CaCO3 exported from the surface to deep water.

References (40)

  • R.D. Pingree

    Flow of surface waters to the west of the British Isles and in the Bay of Biscay

    Deep-Sea Res. II

    40

    (1993)
  • A. Sy

    Investigation of large-scale circulation patterns in the central North Atlantic: the North Atlantic Current, the Azores Current, and the Mediterranean Water plume in the area of the Mid-Atlantic Ridge

    Deep-Sea Res.

    (1988)
  • K. Takahashi et al.

    Planktonic foraminifera: factors controlling sinking speeds

    Deep-Sea Res.

    (1984)
  • R.c. Thunell et al.

    Temporal variability in sediment fluxes in the San Pedro Basin, Southern California Bight

    Cont. Shelf Res.

    (1994)
  • P. Ziveri et al.

    Export production of coccolithophores in an upwelling region: Results from San Pedro Basin, Southern California Borderlands

    Mar. Micropaleontol.

    (1995)
  • A.N. Antia et al.

    Seasonality in sedimentation and episodic flux events in the east Greenland Sea

  • A.W.H.

    Ecology of Recent planktonic foraminifera. Part 2. Bathymetric and seasonal distributions in the Sargasso-Sea off Bermuda

    Micropaleontology

    (1960)
  • W. Beckmann et al.

    Cyclonic coldcore eddy in the eastern North Atlantic. III. Zooplankton

    Mar. Ecol. Prog. Ser.

    (1987)
  • W.H. Berger et al.

    Planktonic Foraminifera: Differential settling, dissolution and redeposition

    Limnol. Oceanogr.

    (1972)
  • J. Bijma

    On the biology of tropical spinose Globigerinidae (Sarcodina, Foraminiferida) and its implications for Paleoecology

  • Cited by (59)

    • Three-dimensional analysis of inter-and intraspecific variation in ontogenetic growth trajectories of planktonic foraminifera

      2020, Marine Micropaleontology
      Citation Excerpt :

      Ontogenetic data for G. ruber, G. siphonifera, and G. inflata presented in Brummer et al., 1987 and Wei et al., 1992 using one- and two-dimensional measurements were also incorporated in our analysis of growth rate patterns. Plankton tow samples from the northern North Atlantic (Table 1, M10-3) were collected with 100-μm nets, stored in pH−8.2 buffered formalin, removed from the liquid after the expedition, and dry-stored until analysis (Schiebel et al., 1995). Sediment trap samples were fixed with 1-%-Na-azide, cool-stored at 0–4 °C, split, and dry-stored until analysis (Lundgreen, 1996).

    View all citing articles on Scopus
    View full text