Nitrogen interception and export by experimental salt marsh plots exposed to chronic nutrient addition
Brin, Lindsay D.
Howes, Brian L.
MetadataShow full item record
KeywordSpartina salt marsh; New England; Nutrient addition; Nitrogen export; Nitrogen uptake; Dissolved inorganic nitrogen; Dissolved organic nitrogen; Nitrate; Ammonium
Mass balance studies conducted in the 1970s in Great Sippewissett Salt Marsh, New England, showed that fertilized plots intercepted 60 to 80% of the nitrogen (N) applied at several treatment levels every year from April to October, where interception mechanisms include plant uptake, denitrification and burial. These results pointed out that salt marshes are able to intercept land-derived N that could otherwise cause eutrophication in coastal waters. To determine the long-term N interception capacity of salt marshes and to assess the effect of different levels of N input, we measured nitrogenous materials in tidal water entering and leaving Great Sippewissett experimental plots in the 2007 growing season. Our results, from sampling over both full tidal cycles and more intensively sampled ebb tides, indicate high interception of externally added N. Tidal export of dissolved inorganic N (DIN) was small, although it increased with tide height and at high N input rates. NH4+ export was generally 2 to 3 times NO3– export, except at the highest N addition, where DIN export was evenly partitioned between NO3– and NH4+. Exports of dissolved organic N were not enhanced by N addition. Overall, export of added N was very small, <7% for all treatments, which is less than earlier estimates. Apparent enhanced tidal export of N from N-amended plots ceased when N additions ended in the fall. Nitrogen cycling within the vegetated marsh appears to limit N export, such that interception of added N remains high even after over 3 decades of external N inputs.
Author Posting. © Inter-Research, 2010. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Marine Ecology Progress Series 400 (2010): 3-17, doi::10.3354/meps08460.
Showing items related by title, author, creator and subject.
Quantifying the production of dissolved organic nitrogen in headwater streams using 15N tracer additions Johnson, Laura T.; Tank, Jennifer L.; Hall, Robert O.; Mulholland, Patrick J.; Hamilton, Stephen K.; Valett, H. Maurice; Webster, Jackson R.; Bernot, Melody J.; McDowell, William H.; Peterson, Bruce J.; Thomas, Suzanne M. (Association for the Sciences of Limnology and Oceanography, 2013-07)Most nitrogen (N) assimilation in lake and marine ecosystems is often subsequently released via autochthonous dissolved organic nitrogen (DON) production, but autochthonous DON production has yet to be quantified in flowing ...
Long-term experimental warming and nutrient additions increase productivity in tall deciduous shrub tundra DeMarco, Jennie; Mack, Michelle C.; Bret-Harte, M. Syndonia; Burton, Mark; Shaver, Gaius R. (Ecological Society of America, 2014-06-19)Warming Arctic temperatures can drive changes in vegetation structure and function directly by stimulating plant growth or indirectly by stimulating microbial decomposition of organic matter and releasing more nutrients ...
Species compositional differences on different-aged glacial landscapes drive contrasting responses of tundra to nutrient addition Hobbie, Sarah E.; Gough, Laura; Shaver, Gaius R. (2005-01-17)In the northern foothills of the Brooks Range, Alaska, moist non-acidic tundra dominates more recently deglaciated upland landscapes, whereas moist acidic tundra dominates older upland landscapes. In previous studies, ...