, Volume 138, Issue 1, pp 23–48 | Cite as

Hydrologic and biogeochemical drivers of dissolved organic carbon and nitrate uptake in a headwater stream network

  • Erin SeyboldEmail author
  • Brian McGlynn


Headwater streams are foci for nutrient and energy loading from terrestrial landscapes, in situ nutrient transformations, and downstream transport. Despite the prominent role that headwater streams can have in regulating downstream water quality, the relative importance of processes that can influence nutrient uptake have not been fully compared in heterotrophic aquatic systems. To address this research need, we assessed the seasonality of dissolved organic carbon (DOC) and nitrate (NO3) uptake, compared the relative influence of hydrologic and biogeochemical drivers on observed seasonal trends in nutrient uptake, and estimated the influence of these biological transformations on watershed scale nutrient retention and export. We determined that seasonal reductions in DOC and NO3 concentrations led to decreases in the potential for the biotic community to take up nutrients, and that seasonality of DOC and NO3 uptake was consistent with the seasonal dynamics of ecosystem metabolism. We calculated that that during the post-snowmelt period (June to August), biotic retention of both dissolved organic carbon and nitrate exceeded export fluxes from this headwater catchment, highlighting the potential for biological processes to regulate downstream water quality.


Dissolved organic Carbon Nitrogen Nutrient uptake TASCC Residence time Watershed export 



Financial support for this project was provided by Duke University, the National Science Foundation (NSF) Graduate Research Fellowship Program, NSF Grant #1114392, and USDA Award #2012-67019-19360. We would like to thank Maggie Zimmer, Kendra Kaiser, Andrew Burch, and Patrick Clay for assistance with fieldwork. We thank the Tenderfoot Creek Experimental Forest for allowing us access to the site and providing logistical support.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Nicholas School of the Environment, University Program in EcologyDuke UniversityDurhamUSA
  2. 2.Division of Earth and Ocean Sciences, Nicholas School of the EnvironmentDuke UniversityDurhamUSA

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