Short-term sedimentation pulses recorded with a fluorescence sensor and sediment traps at 900-m depth in the Canary basin

Abstract

We observed short-term peaks in pigment fluorescence and backscattering using optical sensors combined with time-series sediment traps at ~ 900-m depth at an oligotrophic site in the Canary Island region. These events were observed in late winter to early spring and lasted only a few hours to a few days. The events generally coincided with late winter to early spring flux maxima recorded by the traps. Surprisingly, microscopic analyses showed no evidence of sedimentation of intact phytoplankton cells during the fluorescence peaks. However, we observed well-preserved zooplankton fecal pellets containing densely packed coccoliths and, presumably, large amounts of chlorophyll-derived pigments.