Biogeosciences, 10, 7179–7194, 2013 Open Access www.biogeosciences.net/10/7179/2013/ doi:10.5194/bg-10-7179-2013 Biogeosciences © Author(s) 2013. CC Attribution 3.0 License. A nitrogen budget for the Strait of Georgia, British Columbia, with emphasis on particulate nitrogen and dissolved inorganic nitrogen J. N. Sutton1,2, S. C. Johannessen1, and R. W. Macdonald1 1Institute of Ocean Sciences, Fisheries and Oceans Canada, 9860 West Saanich Road, P.O. Box 6000, Sidney, British Columbia, V8L 4B2, Canada 2Department of Earth and Planetary Science, University of California, Berkeley, California, 94720, USA Correspondence to: J. N. Sutton (
[email protected]) Received: 6 March 2013 – Published in Biogeosciences Discuss.: 23 April 2013 Revised: 29 September 2013 – Accepted: 10 October 2013 – Published: 12 November 2013 Abstract. Balanced budgets for dissolved inorganic N (DIN) 1 Introduction and particulate N (PN) were constructed for the Strait of Georgia (SoG), a semi-enclosed coastal sea off the west coast of British Columbia, Canada. The dominant control on the The nitrogen (N) cycle is a crucial underpinning of marine N budget is the advection of DIN into and out of the SoG biological productivity (Gruber and Galloway, 2008). Dur- via Haro Strait. The annual influx of DIN by advection from ing the past 150 yr, the global N cycle has been dramati- the Pacific Ocean is 29 990 (±19 500) Mmol yr−1. The DIN cally changed by human activities that have loaded reactive N flux advected out of the SoG is 24 300 (±15 500) Mmol yr−1. into ecosystems in amounts that rival natural sources (Rabal- Most of the DIN that enters the SoG (∼ 23 400 Mmol yr−1) ais, 2002; Galloway et al., 2004).