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Communication at the NABS Annual meeting, Keystone, 2000
(303) CONTROL OF DIN EXPORT FROM SMALL WATERSHEDS BY HEADWATER STREAM NITROGEN PROCESSING.
B.J. Peterson1, W.M. Wollheim2, P.J. Mulholland3, J.R. Webster4, J.L. Tank5, J.L. Meyer6, N.B. Grimm7, E. Marti7, W.B. Bowden8, J. Merriam9, H.M. Valett4, A.E. Hershey10, W.H. McDowell9, W.K. Dodds11, S.K. Hamilton12, S.L. Johnson13, L.R. Ashkenas13, and D.J. D'Angelo14. 1The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, 2Complex Systems Research Center, University of New Hampshire, Durham, NH 03824, 3Environmental Science Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6036, 4Department of Biology, Virginia Tech University, Blacksburg, VA 24061, 5Department of Natural Resources and Environmental Sciences, N-411 Turner Hall, University of Illinois, 1102 S. Goodwin Ave., Urbana, IL 61801, 6Institute of Ecology, University of Georgia, Athens, GA 30602-2602, 7Department of Biology, Arizona State University, Tempe, AZ 85287-1501, 8Landcare Research, PO Box 69, Lincoln 8152, New Zealand, 9Department of Natural Resources, James Hall, Durham, NH 03824, 10Department of Biology, University of North Carolina - Greensboro, Greensboro, NC 27402, 11Ackert Hall, Division of Biology, Kansas State University, Manhattan, KS 66506, 12Kellogg Biological Station, 3700 E. Gull Creek Dr., Hickory Corners, MI 49060, 13Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR 97331, 14The Proctor and Gamble Co., Experimental Stream Facility, 1003 Route 50, Milford, OH 45150-0356
We used the Lotic Intersite Nitrogen eXperiment (LINX) project data base on ammonium uptake, nitrate uptake, nitrification, and net inorganic nitrogen regeneration from stream bottoms to calculate how in-stream processes can alter NH4 and NO3 concentrations in headwater streams. A spreadsheet model was used to predict how seepage water nutrient concentrations would be changed by these in-stream processes. The data on rates of each process were used to explore how sensitive export concentrations were to variations in the intensity of each process. In the average case (mean LINX kinetics) seepage waters entering the small stream channel were assigned concentrations of 20 µg/l and 50 µg/l for NH4 and NO3 respectively. The predicted stream water concentrations at 1 km from the stream origin were 3 µg/l NH4 and 21µg/l NO3. In this case about 67% of the DIN input would be retained or transformed by the headwater stream. Exploration of the ranges of kinetics across all LINX streams produced DIN retention estimates ranging from 0 to 88% of inputs.
Presented at 1:00 PM on Thursday, June 1, 2000 in Nutrient Dynamics I
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