Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Biogeosciences, 10, 7323-7331, 2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
15 Nov 2013
Solute-specific scaling of inorganic nitrogen and phosphorus uptake in streams
R. O. Hall Jr.1, M. A. Baker2, E. J. Rosi-Marshall3, J. L. Tank4, and J. D. Newbold5 1Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, 82071, USA
2Department of Biology and Ecology Center, Utah State University, Logan, Utah, 84322, USA
3Cary Institute of Ecosystem Studies, Box AB, Millbrook, New York, 12545, USA
4Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
5Stroud Water Research Center, 970 Spencer Road, Avondale, Pennsylvania, 19311, USA
Abstract. Stream ecosystem processes such as nutrient cycling may vary with stream position in the network. Using a scaling approach, we examined the relationship between stream size and nutrient uptake length, which represents the mean distance that a dissolved solute travels prior to removal from the water column. Ammonium (NH4+) uptake length increased proportionally with stream size measured as specific discharge (discharge/stream width) with a scaling exponent = 1.01. In contrast, uptake lengths for nitrate (NO3) and soluble reactive phosphorus (SRP) increased more rapidly than increases in specific discharge (scaling exponents = 1.19 for NO3 and 1.35 for SRP). Additionally, the ratio of inorganic nitrogen (N) uptake length to SRP uptake length declined with stream size; there was relatively lower demand for SRP compared to N as stream size increased. Finally, we related the scaling of uptake length with specific discharge to that of stream length using Hack's law and downstream hydraulic geometry. Ammonium uptake length increased less than proportionally with distance from the headwaters, suggesting a strong role for larger streams and rivers in regulating nutrient transport.

Citation: Hall Jr., R. O., Baker, M. A., Rosi-Marshall, E. J., Tank, J. L., and Newbold, J. D.: Solute-specific scaling of inorganic nitrogen and phosphorus uptake in streams, Biogeosciences, 10, 7323-7331,, 2013.
Publications Copernicus