Aquatic Sciences Meeting, Albuquerque 2001

SS16 Iron Bioavailability and Limitation to Primary Production (Disciplinary Connections)

Date: Monday, February 12, 2001, Time: 2:00:00 PM

Location: Mesilla

Franck, V, M, Marine Science Institute, University of California, Santa Barbara, USA, franck@lifesci.ucsb.edu

Brzezinski, M, A, Marine Science Institute, University of California, Santa Barbara, USA, brzezins@lifesci.ucsb.edu

Hutchins, D, A, College of Marine Studies, University of Delaware, Lewes, USA, dahutch@udel.edu

Bruland, K, W, Ocean Sciences Department, University of California, Santa Cruz, USA, bruland@cats.ucsc.edu

Coale, K, H, Moss Landing Marine Laboratories, Moss Landing, USA, coale@mlml.calstate.edu

EFFECT OF IRON ON Si AND N UPTAKE KINETICS IN SHIPBOARD BOTTLE ENRICHMENT EXPERIMENTS

The effect of Fe on nutrient uptake kinetics was examined in shipboard enrichment experiments off California, USA (37°–38°N, 122–124°W) and in the Pacific Sector of the Southern Ocean (62°–68°S, 170°W). Our results show no effect of Fe on Ks, but Vmax values for both silicic acid and nitrate are significantly lower when dissolved Fe concentrations are <1nM. Fe concentrations of 0.1–0.5nM off the coast of CA resulted in two-fold lower Vmax values compared to those at 10nM Fe. In the Southern Ocean, Fe concentrations of ~0.02–0.10nM Fe resulted in up to three-fold lower Vmax values relative to those at 2.5nM Fe. These results suggest that Fe and nutrient co-limitation may regulate productivity in HNLC regions.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks