Nutrients flow from runoff at burned forest site in Lake Tahoe Basin
W. Wally Miller
Dale E. Johnson
Theresa M. Loupe, Inter-Disciplinary Hydrologic Sciences Program
James S. Sedinger
Erin M. Carroll, Natural Resources and Environmental Science
James D. Murphy, Hydrologic Sciences Program
Roger F. Walker
Dallas Glass, Inter-Disciplinary Hydrologic Sciences Program
California Agriculture 60(2):65-71. DOI: 10.3733/ca.v060n02p65.
The long-term trend toward decreased water clarity in Lake Tahoe is well documented, and is strongly linked to increased nitrogen and phosphorus loading from surrounding watersheds. Recent research has detected very high concentrations of biologically available nitrogen and phosphorus in overland/litter interflow from Sierra ecosystems. The objective of this study was to assess the effect of a localized wildfire on the nutrient content of such runoff. The wildfire increased the frequency and magnitude of elevated nutrient concentrations in discharge runoff for all three parameters studied (nitrate nitrogen, ammonium nitrogen and phosphate phosphorus). Although the mobilization of nutrients was increased due to wildfire, the lack of O horizon material (the surface organic layers of mineral soils) after burning may ultimately reduce discharge concentrations over time.
W.W. Miller is Professor; D.W. Johnson is Professor; T.M. Loupe is Graduate Student, Inter-Disciplinary Hydrologic Sciences Program; J.S. Sedinger is Professor; E.M. Carroll is Graduate Student, Natural Resources and Environmental Science; J.D. Murphy is Graduate, Hydrologic Sciences Program; R.F. Walker is Professor; D. Glass is Graduate Student, Inter-Disciplinary Hydrologic Sciences Program;
(now with the Nevada Department of Transportation, Carson City, Nev.); all within the Department of Natural Resources and Environmental Science, College of Agriculture, Biotechnology, and Natural Resources, University of Nevada, Reno. This research was supported in part by the Nevada Agricultural Experiment Station (Pub. no. 52042973). We gratefully acknowledge contributions from the U.S. Forest Service Lake Tahoe Basin Management Unit and Joint Fire Sciences Program.