The Xiamen Symposium on Marine Environmental Sciences

2027 Xiamen Symposium on Marine Environmental Sciences

January 12-15, 2027

Sources and cycling of particulate trace metals in the South Atlantic Ocean
ID:234 Oral Presentation

2027-01-13 09:15 (China Standard Time)

Session: Session 8 - Trace metal biogeochemical cycles in the ocean

Abstract
The particulate phase is fundamental to the oceanic inventory, transport, and bioavailability of trace metals (TMs), yet their basin-scale dynamics remain poorly understood. Here, we investigated the distributions of particulate TMs (pTMs) along 40°S (GEOTRACES GA10 transect) in the South Atlantic Ocean. Labile and refractory pTM concentrations spanned six orders of magnitude from 10⁻1 to 106 pmol kg⁻1. Refractory pTMs were associated with lithogenic particles and labile pTMs were linked to biogenic and authigenic particles. Near the Río de la Plata estuary, labile and refractory pTMs were enhanced by fluvial discharge and sediment resuspension in the coastal region. Benthic inputs in the Argentine Basin (>4000 m) induced strong near-bottom enrichments of pTMs with the labile fraction of the particles contributing 30–75% of total concentration. In addition, the ratios between labile pCo, pNi, pCu, pZn and labile particulate phosphorus increased by 5–100 times from surface to bottom waters, reflecting particle cycling, remineralization with preferential phosphorus release, scavenging, and benthic inputs. At depths, Mn, Pb, and Co showed active dissolved-labile particulate TM exchange and boundary influence, while Ni, Cu, Zn, and Cd were increasingly dominated by the dissolved phase with increasing depth. This demonstrates that separating labile and refractory particulate fractions is critical for resolving ocean TMs cycles. These findings highlight the fundamental role of particle cycling in regulating the transport, transformation, and bioavailability of TMs in the South Atlantic Ocean.
Speaker
Yuping Guo Geomar Helmholtz Centre for Ocean Research Kiel

Author
Yuping Guo Geomar Helmholtz Centre for Ocean Research Kiel

    Important Dates

    • Jan 30

      2026

      Session / Event proposals open

    • Mar 31

      2026

      Session / Event proposals close
      (Extended to April 7)

    • Apr 30

      2026

      Session acceptance notifications

    • Apr 30

      2026

      Abstract submissions & registration open

    • Jun 30

      2026

      Abstract submissions close
      (Extended to July 21)

    • Aug 31

      2026

      Abstract acceptance notifications

    • Sep 15

      2026

      Scientific program released

    • Oct 15

      2026

      Early bird registration closes

    • Jan 12–15

      2027

      XMAS 2027