Manganese Flux from Continental Margin Sediments in a Transect Through the Oxygen Minimum
Kenneth S. Johnson 1,
William M. Berelson 2,
Kenneth H. Coale 3,
Teresa L. Coley 3,
Virginia A. Elrod 3,
W. Russell Fairey 3,
Helen D. Iams 2,
Tammy E. Kilgore 2, and
Jocelyn L. Nowicki 3
1 Moss Landing Marine Laboratories, Post Office Box 450, Moss Landing, CA 95039, and Monterey Bay Aquarium Research Institute, 160 Central Avenue, Pacific Grove, CA 93950
2 Department of Geological Sciences, University of Southern California, Los Angeles, CA 90089
3 Moss Landing Marine Laboratories, Post Office Box 450, Moss Landing, CA 95039
The flux of manganese from continental margin sediments to the ocean was measured with a free-vehicle, benthic flux chamber in a transect across the continental shelf and upper slope of the California margin. The highest fluxes were observed on the shallow continental shelf. Manganese flux decreased linearly with bottom water oxygen concentration, and the lowest fluxes occurred in the oxygen minimum zone (at a depth of 600 to 1000 meters). Although the flux of manganese from continental shelf sediments can account for the elevated concentrations observed in shallow, coastal waters, the flux from sediments that intersect the oxygen minimum cannot produce the subsurface concentration maximum of dissolved manganese that is observed in the Pacific Ocean.
Submitted on April 3, 1992
Accepted on June 25, 1992
