Organic Ligands—A Key Control on Trace Metal Biogeochemistry in the Ocean

This WG’s aim is to improve scientists’ understanding of the role of organic metal-binding ligands in oceanic biogeochemistry through an interdisciplinary collaboration of members comprising trace metal biogeochemists, organic geochemists, and biogeochemical modelers.

Organic metal-binding ligands control the bioavailability of trace metals and thus influence pivotal global elemental cycles, such as those of carbon and nitrogen. To date, the sources, chemical structures, and degradation mechanisms of organic metal-binding ligands are still not well understood, making it difficult to model them with sufficient confidence to predict how they, and consequently trace metal cycles, will respond to projected global alteration of continental aridity (dust supply), ocean acidification, and oceanic oxygen minimum zones due to a changing climate.

Consequently, the overarching goals of SCOR WG 139 are to:

  1. Promote improvements in quality, accessibility, and development of analytical methodologies for characterizing metal-binding ligands in seawater
  2. Characterize which components of the dissolved organic matter pool make a significant contribution to the biogeochemistry of trace metals in the oceans
  3. Identify the role of ligands in microbial ecology and marine biogeochemical cycles.

The WG has met for the first time in February following the joint 2012 Ocean Sciences Meeting. It was decided to facilitate a new intercalibration exercise, completing summaries of important building blocks (e.g., methods currently applied, time series ligand data, and biochemical path-ways of trace metals) for the best practices guide, and identifying additional funding sources to drive this project forward (see meeting notes ).

A second meeting of SCOR WG 139 is planned for the 2013 ASLO Aquatic Sciences Meeting, to be held in New Orleans, Lousiana, USA. A special session will aslo be held during the 2013 ALSO meeting to encourage scientists interested in the goals of WG 139 to take part in the discussion and actions necessary to fulfill the Terms of References.