Physical Sciences and Mathematics Commons^™

The Fate Of Nitrogren Fixed By Diazotrophs In The Ocean, Margaret R. Mulholland

OES Faculty Publications

While we now know that N₂ fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N₂ fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or does it contribute primarily to bacterial productivity and respiration in the euphotic zone? For Trichodesmium, the diazotroph we know the most about, the transfer of recently fixed N₂ (and C) appears …