Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/6/2015
Publication Date: 2/6/2015
Citation: Blank, R.R., Clements, D.D., Morgan, T.A., Harmon, D.N. 2015. Sagebrush wildfire effects on soil chemistry: A temporal and spatial study [abstract]. Society for Range Management Meeting Abstracts. p. 10.
Technical Abstract: In sagebrush ecosystems, surface soil nutrient availability, particularly of N, often increases immediately following wildfire. However, little is known on how soil N availability and other nutrients, change over time post-wildfire. In October 2013, a wildfire approximately 30 km north of Reno, NV occurred in a Wyoming big sagebrush community. An experiment was designed to quantify post-fire surface soil chemistry (0-10 cm) by microsite (burned and unburned canopy, burned and unburned interspace) and temporally (monthly from Nov., 2013 through June, 2015). We report on data collected through Aug., 2014. Changes in nutrient availability due to wildfire largely occurred in sagebrush canopy microsites. For all months, burned sagebrush canopies averaged nearly nine times greater in mineral N, mostly due to elevated NH4+-N, relative to unburned sagebrush canopies. After a 30-day laboratory incubation period, total mineral nitrogen was greater on burned shrub canopies than unburned. Burned sagebrush canopies also had greater DTPA-Mn (6 times), solution-phase SO4-2 (12 times), and solution-phase ortho-P (2 times) availabilities than unburned sagebrush canopies. Except for solution-phase ortho-P, the magnitude of differences in nutrients between burned and unburned canopies did not decline over the months measured. In a complimentary post-fire rehabilitation study, burned canopy microsites fostered greater seedling density and plant growth than burned interspaces, possibly due to greater availability of nitrogen and phosphorus.