Abstract

Erosion of bulk and pyrogenic carbon (C) impose significant controls on storage and persistence of soil organic matter (SOM) in eroding watershed. The extent of both bulk and BC export from eroding watersheds depends on amount and composition of SOM, association of SOM with reactive soil minerals in eroding slope profiles, the type and rate of erosion, and time since and severity of past fires. Currently, we have very little data on the relative lateral distribution and export of bulk vs. pyrogenic C from eroding upland, fire-affected forested ecosystems. Here, we will present data on the amount and composition of soil material eroded from eight first-order watersheds in the mixed-conifer zone of the Sierra National Forest in the Kings River Experimental Watershed. Our results show that there is large variability in nature of exported material – including ratio of bulk sediment vs. BC content, chemical composition of SOM, rate of export of reactive soil minerals, and overall sediment export across the watersheds that is not directly related to watershed size or climatic variability.

Citation

Berhe, A.A., Stacy, E.M., McClintock, M., Newman, A., Hart, S.C., Hunsaker, C.T., Johnson, D.W. (2012): Erosion of bulk and pyrogenic C from upland forested Sierra Nevada ecosystems (Invited). Fall meeting, American Geophysical Union, December 2012. Abstract B34C-08..