Submitted to: Wildland Shrub Symposium Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: January 4, 2006
Publication Date: June 16, 2006
Citation: Rau, B.M., Blank, R.R., Morgan, T.A. 2006. Microsite and time since prescribed fire's influence on soil microbiology in a pinyon-juniper woodland [abstract]. Wildland Shrub Symposium - Shrublands Under Fire, June 6-8, 2006, Cedar City, Utah. Technical Abstract: Pinyon-juniper (Pinus monophylla Torr. & Fremont - Juniperus osteosperma Torr.) encroachment into sagebrush grasslands is a continuing problem in arid regions of the western United States. Woodland encroachment is not easily reversible which may be due to several factors including loss of native perennial seedbanks, monoterpenes produced by pinyon and juniper, and changes in microbial communities under pinyon. Prescribed burning has been suggested as a tool to slow woodland encroachment. We examined surface soil (0-15 cm) microbial community structure using Phospholipid Fatty Acid (PLFA) analyses to determine differences between adjacent burned (2002 and 2004) and unburned woodlands at two microsites (under tree canopies and tree canopy interspaces). Tree canopy interspace microsites had a greater concentration of total PLFA and Eukaryotes. Conversely under tree canopy microsites had a greater percentage of fermicutes, anaerobic metal reducers, and higher PLFA Cis / Trans fatty acid ratio. Time since burning increased Eukaryote PLFA in both microsites.