Effects of Nitrogen Fixation by Ceanothus velutinus on Soil Fertility and Surface Water Runoff in Post Fire Forest Ecosystems. (3921)
Authors:
C.M. Stein* - Univ. of Nevada, Reno D.W. Johnson - Univ. of Nevada, Reno W.W. Miller - Univ. of Nevada, Reno
P. Verberg - Desert Research Inst. Reno, NV J.D. Murphy - Univ. of Nevada, Reno
Abstract:
Soil solutions and soils were collected from adjacent Ceanothus velutinus and Manzanita Aretostaphylus patula, as well as a neighboring Jeffrey pine Pinus jeffreyi stand and Manzanita that was found alone in the forest and in the shrub. It was hypothesized that the Ceanothus ecosystem would contribute higher
concentrations of NH4-N and NO3-N due to its nitrogen fixation ability. This
hypothesis was not supported. Resin lysimeters showed that the pine ecosystem had a significantly higher concentration of NO3-N than the Ceanothus ecosystem at both the O and A horizons, however, there was no significant difference found for the NH4-N concentration. Resin capsules also showed a significantly higher
concentration of NO3-N in the pine ecosystem, as well as a significantly higher concentration of NH4-N. The effects of the N2 fixing potential of Ceanothus velutinus on surface water quality are poorly known in the Sierra Nevada.
Preliminary studies in Little Valley, NV show the pine ecosystem having significantly greater levels of NH4-N, NO3-N in the soil solution than the Ceanothus ecosystem.
Speaker Information: Chad Stein, Univ. of Nevada, Reno, 2185 Ivory Gull Ct., Sparks, NV 89436; Phone: 775 425-5767; E-mail: [email protected]
Session Information: Monday, November 1, 2004, 2:00 PM-4:00 PM Presentation Start: 2:00 PM (Poster Board Number: 2238)
Keywords: Soil Chemistry; Biogeochemistry; Soil Fertility; Surface Water Runoff