Bioturbational mixing depth and carbon flux at the seafloor

Abstract

Radiocarbon dating series, bulk sediment, and organic carbon flux from various Atlantic deep-sea regions reveal that the thickness of the bioturbated zone increases by 2 cm if food supply increases by 1 gCm-2yr-1 (r = 0.8). Bulk sediment accumulation rates do not influence the depth of bioturbational mixing under normal pelagic sedimentary conditions. We believe that this relationship between nutrient supply and benthic mixing can be used for a quantitative and time-variable unmixing procedure to improve high-resolution stratigraphic correlations and paleoclimatic interpretations of deep-sea records.