Nitrogen dynamic in Eurasian coastal Arctic ecosystem: Insight from nitrogen isotope.

Thibodeau, Benoit, Bauch, Dorothea and Voss, Maren (2017) Nitrogen dynamic in Eurasian coastal Arctic ecosystem: Insight from nitrogen isotope. Open Access Global Biogeochemical Cycles, 31 (5). pp. 836-849. DOI 10.1002/2016GB005593.

[thumbnail of gbc20542(2).pdf]
Preview
Text
gbc20542(2).pdf - Published Version

Download (3MB) | Preview

Supplementary data:

Abstract

Primary productivity is limited by the availability of nitrogen (N) in most of the coastal Arctic, as a large portion of N is released by the spring freshet and completely consumed during the following summer. Thus, understanding the fate of riverine nitrogen is critical to identify the link between dissolved nitrogen dynamic and coastal primary productivity to foresee upcoming changes in the Arctic seas, such as increase riverine discharge and permafrost thaw. Here, we provide a field-based study of nitrogen dynamic over the Laptev Sea shelf based on isotope geochemistry. We demonstrate that while most of the nitrate found under the surface fresh water layer is of remineralized origin, some of the nitrate originates from atmospheric input and was probably transported at depth by the mixing of brine-enriched denser water during sea-ice formation. Moreover, our results suggest that riverine dissolved organic nitrogen (DON) represents up to 6 times the total riverine release of nitrate and that about 62 to 76% of the DON is removed within the shelf waters. This is a crucial information regarding the near-future impact of climate change on primary productivity in the Eurasian coastal Arctic.

Document Type: Article
Keywords: Climate Change; Arctic; primary productivity; Nitrogen; carbon; anthropogenic impact; RV Viktor Buynitskiy
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-P-OZ Paleo-Oceanography
Refereed: Yes
Open Access Journal?: No
Publisher: AGU (American Geophysical Union), Wiley
Projects: Laptev Sea System, CATS
Date Deposited: 02 May 2017 07:47
Last Modified: 06 Feb 2020 09:17
URI: https://oceanrep.geomar.de/id/eprint/37745

Actions (login required)

View Item View Item