ARS | Publication request: Brush management effects on soil carbon sequestration in sagebrush-dominated rangelands

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 30, 2011
Publication Date: December 30, 2011
Citation: Derner, J.D., Vance, G.F., Schuman, G.E., Follett, R.F. 2011. Brush management effects on soil carbon sequestration in sagebrush-dominated rangelands. Society for Range Management Meeting Abstracts No. 0078.

Technical Abstract: Scientific information regarding soil organic carbon (SOC) sequestration in western rangelands, especially those with a sagebrush (Artemisia spp.) component and in lower rainfall areas (<350 mm), remains a major knowledge gap in understanding the effects of land management. We sampled soils from two contrasting ecological sites (Sandy with 175 to 225 mm precipitation and Loamy with 250 to 350 mm precipitation) in southwestern Wyoming with paired sets of brush management treatments. For the Sandy ecological site, we sampled a control site dominated by Wyoming big sagebrush (Artemisia tridentata spp. wyomingensis) compared to a 2002 mowed site with a native cool-season understory of rhizomatous wheatgrasses. At the Loamy ecological site, we compared control sites dominated by Wyoming big sagebrush to sites that were: a) mowed in 1997 and b) herbicided with Spike® 20P (tebuthiuron) in 1997. Both brush treatment sites contained a native cool-season understory of rhizomatous wheatgrasses. Soil samples were collected to 60 cm depth in May 2009 from two randomly located 50 m transects at each sampling site. The brush treatment of mowing did not affect the SOC at either the Sandy or the Loamy ecological site. However, herbicide application in 1997 at the Loamy ecological site increased the SOC in both the 0-5 (42.6% increase) and 5-15 (16.8% increase) cm depth increments. Although application of brush treatments in sagebrush-dominated rangelands can markedly affect vegetation responses, only the herbicide application treatment enhanced the SOC response. Our findings provide evidence that these arid rangelands have the capacity to sequester SOC in response to vegetation manipulation.