USGS visual identity mark and link to main Web site at

The Role of Speciation and Provenance in the Bioavailability of Iron in the Gulf of Alaska: Andrew Schroth

Project Title: The Role of Speciation and Provenance in the Bioavailability of Iron in the Gulf of Alaska
Mendenhall Fellow: Andrew W. Schroth (508) 457-2295,
Duty Station: Woods Hole, MA
Start Date: October 1, 2007
Education: M.S. Geochemistry, Northern Arizona University (2001); Ph.D. Geochemistry, Dartmouth College (2007)
Research Advisors: John Crusius, (508) 457-2353,; Ken Bruland (UCSC), (831) 459-4587,; Ed Sholkovitz (WHOI), (508) 289-2346,
  Andrew W. Schroth

Project Description: Although ubiquitous and often enriched in the continental crust, iron (Fe) is only present at trace level dissolved concentrations in most marine waters and is thought to be the limiting nutrient to primary productivity in many areas of the ocean. In such areas, Fe limitation of plankton growth may influence the amount of carbon sequestration associated with algal export and the stock of fish populations in ‘bottom up’ ecosystems. While the distribution of dissolved iron throughout much of the world’s oceans is known or estimated at various spatial scales, a comprehensive understanding of the role of individual continental sources of Fe (aeolian dust, riverine input, continental shelf sediment resuspension, subterranean groundwater discharge, and remobilization during diagenesis of sediments) to the marine environment and the relative bioavailability of each Fe source remains elusive. A mechanistic model of the delivery of potentially bioavailable forms of Fe from the continent to marine waters is required to predict ecosystem response to the various forms of iron, its coupling to carbon cycling, and its response to current and future environmental change.

The objective of this study is to quantify and mechanistically describe the generation and delivery of bioavailable Fe from airborne and riverine sources to the Gulf of Alaska, with emphasis on the role of glaciers and variable bedrock mineralogy in this process.

Specifically, this work will:

Go back to Previous Profile   Project Profiles   Next Profile Go forward to

Direct inquiries to Rama K. Kotra at
Page Contact Information: Mendenhall Postdoctoral Fellowship Program Web Team
Last modified: 16:08:32 Thu 13 Dec 2012