|Blank, Robert - Bob|
Submitted to: Rangeland Ecology and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2009
Publication Date: 2/15/2010
Publication URL: http://parking.nal.usda.gov/shortterm/21166_rue_rem_carbon.pdf
Citation: Rau, B.M., Tausch, R., Reiner, A., Johnson, D.W., Chambers, J.C., Blank, R.R., Lucchesi, A. 2010. Influence of Prescribed Fire on Ecosystem Biomass, Carbon, and Nitrogen in a Pinyon Juniper Woodland. Rangeland Ecology and Management. 63:197-202. Interpretive Summary: Pinyon and juniper woodland expansion in the Great Basin, associated with climate change, offers the potential to sequester carbon (C). We quantified the effects of prescribed fire, as a fuel reduction and ecosystem maintenance treatment, on ecosystem C, and N. Plots containing 30% tree cover averaged nearly 80,000 kg ha-1 ecosystem C, and 5,000 kg ha-1 ecosystem N. Prescribed burning resulted in a 68% reduction in aboveground C, and a 78% reduction in aboveground N. Estimating long-term potential to store C in these ecosystems depends on greater understanding of the dynamics of C storage in soils.
Technical Abstract: Pinyon and juniper woodland encroachment associated with climate change and land use history in the Great Basin is thought to provide offsets for carbon emissions. However, the largest pools of carbon in arid landscapes are typically found in soils, and aboveground biomass cannot be considered long term storage in fire prone ecosystems. The objectives of carbon storage also conflict with landscape management for ecosystem services and fuels reduction. We attempt to quantify the effects of prescribed fire as a fuel reduction and ecosystem maintenance treatment on fuel loads, ecosystem carbon, and nitrogen. We found that plots containing 30% tree cover averaged nearly 40,000 kg ha-1 in aboveground biomass, 80,000 kg ha-1 ecosystem C, and 5,000 kg ha-1 ecosystem N. Only 45% of ecosystem C and 10% of ecosystem N resided in biomass pools. Prescribed burning resulted in a 65% reduction in aboveground biomass, a 68% reduction in aboveground C, and a 78% reduction in aboveground N. However, due to temporal variation in soil C and N pools, their size relative to aboveground pools, and the difficulty in obtaining consistent measurements no statistically significant change in ecosystem C occurred, and, although unrealistic, a statistical increase in ecosystem N occurred after the burn.