Marine Biology Commons^™

Dinitrogen Fixation And Release Of Ammonium And Dissolved Organic Nitrogen By Trichodesmium Ims101, Margaret R. Mulholland, Deborah A. Bronk, Douglas G. Capone

OES Faculty Publications

Two methods used to measure dinitrogen (N₂) fixation (acetylene reduction and ¹⁵N₂ uptake) often result in different N₂ fixation rates. Part of the discrepancy may arise from the observation that Trichodesmium can release a fraction of their recently fixed N₂ as dissolved organic nitrogen (DON) and/or ammonium (NH4 ⁺). To resolve outstanding issues regarding N₂ fixation and the production of dissolved combined nitrogen (N) by Trichodesmium, we conducted a comprehensive analysis of N₂ fixation and the production of DON and NH₄⁺ in cultures of Trichodesmium IMS101. We performed …