Program and Agenda

Abstract

NITRIFIER-DENITRIFICATION AS A SOURCE OF NITROUS OXIDE IN THE LOWER EUPHOTIC ZONE OF THE OLIGOTROPHIC NORTH PACIFIC SUBTROPICAL GYRE AT STATION ALOHA

Understanding the role of the oceans in the Earth’s changing climate requires comprehension of the metabolic pathways which produce climatically important trace gases such as nitrous oxide. In this study, we investigated the role of nitrite in the production of nitrous oxide, focusing on the base of the euphotic zone, at the primary nitrite maximum. A series of water column measurements alongside in situ and deckboard experiments were conducted at Station ALOHA in the North Pacific Subtropical Gyre to investigate the conditions whereby nitrite is reduced to nitrous oxide. It was observed that the addition of 15N-labeled nitrite both to seawater collected at 150 m and particles collected in sediment traps yielded a greater enrichment of δ15N2O compared to the addition of 15N-labeled ammonium. Our findings provide evidence for the presence of an active nitrifer-denitrification pathway in the lower euphotic zone of the open ocean, whereby nitrite is reduced to nitrous oxide by ammonia oxidizing microorganisms.

ePoster:

Authors

Wilson, S. T., University of Hawaii, USA, stwilson@hawaii.edu

Del Valle, D. A., University of Hawaii, USA, dadv@hawaii.edu

Segura-Noguera, M., University of Hawaii, USA, mariona.segura@gmail.com

Karl, D. M., University of Hawaii, USA, dkarl@hawaii.edu

Details

Poster presentation

Session #:043
Date: 2/24/2014
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall

Presentation is given by student: No

PosterID: 32