%0 journal article
%@ 0024-3590
%A Gao, H., Matyka, M., Liu, B., Khalili, A., Kostka, J.E., Collins, G., Jansen, S., Holtappels, M., Jensen, M.M., Badewien, T.H., Beck, M., Grunwald, M., de Beer, D., Lavik, G., Kuypers, M.M.M.

%D 2012
%J Limnology and Oceanography
%N 1
%P 185-198 
%R doi:10.4319/lo.2012.57.1.0185
%T Intensive and extensive nitrogen loss from intertidal permeable sediments of the Wadden Sea
%U https://doi.org/10.4319/lo.2012.57.1.0185
1 
%X Nitrogen (N) loss rates were determined in permeable sediments of the Wadden Sea using a combination of stable N isotope incubation experiments and model simulation approaches during three seasons. Three different incubation methods that employed the isotope pairing technique were used: intact core incubations simulating either (1) diffusive or (2) advective transport conditions and (3) slurry incubations. N loss rates from core incubations under simulated advective transport conditions exceeded those rates measured under diffusive transport conditions by 1-2 orders of magnitude, but were comparable to those observed in slurry incubations. N loss rates generally showed little seasonal and spatial variation (207 ± 30 µmol m-2 h-1) in autumn 2006 and spring and summer 2007. Utilizing an extensive time series of nutrient concentrations and current velocities obtained from a continuous monitoring station, nitrate and nitrite (i.e., NO−x) flux into the sediment was modeled over a full annual cycle. Fluxes were sufficient to support the experimentally derived N loss rates. Combining the measured rates with the modeled results, an annual N removal rate of 745 ± 109 mmol N m-;2 yr-1 was estimated for permeable sediments of the Wadden Sea. This rate agrees well with previous N loss estimates for the Wadden Sea based on N budget calculations. Permeable sediments, accounting for 58-70% of the continental shelf area, are an important N sink and their contribution to the global N loss budget should be reevaluated.