HR: 16:15h
AN: B34A-02    [Abstracts]
TI: From Fireproof Desert to Flammable Grassland: Buffelgrass Invasion in the Sonoran Desert
AU: * Betancourt, J L
EM: jlbetanc@usgs.gov
AF: U.S. Geological Survey, Desert Laboratory, 1675 W. Anklam Rd., Tucson, AZ 85745, United States
AB: Only a few decades ago, the Sonoran Desert of northwestern Mexico and southern Arizona was considered mostly fireproof, a case of not enough fine fuel to connect the dominant shrubs and cacti. This has changed with invasions by non-native, winter annual and summer-flower perennial grasses that are rapidly transforming fireproof desert into flammable grassland. Of particular concern is buffelgrass, Pennisetum ciliare, a fire-prone and invasive African perennial grass that has already converted millions of hectares across Sonora since the mid-1960s and has made quick headway in southern and central Arizona beginning in the 1980s. Near Tucson and Phoenix, AZ, buffelgrass invasion is proceeding exponentially, with population expansion (and the costs of mitigation) more than doubling every year. As this conversion progresses, there will be increased fire risks, lost tourist revenue, diminished property values, insurmountable setbacks to conservation efforts, and the threat of large ignition fronts in desert valleys routinely spreading into the mountains. Although somewhat belated, an integrated, multi-jurisdictional effort is being organized to reduce ecological and economic impacts. My presentation will summarize the history and context of buffelgrass introduction and invasion, the disconnect in attitudes and policies across state and international boundaries, ongoing management efforts, the role of science and responsibilities of scientists, accelerated spread with changing climate, and impacts to regional ecosystems and economies. This narrative may serve as a template for other semi-arid lands where buffelgrass and similar grasses have become invasive, including Australia, South America, and many islands in the Pacific Ocean (including Hawaii), Indian Ocean, and Caribbean Sea.
UR: http://www.buffelgrass.org
DE: 1600 GLOBAL CHANGE
DE: 1800 HYDROLOGY
DE: 3300 ATMOSPHERIC PROCESSES
DE: 6600 PUBLIC ISSUES
SC: Biogeosciences [B]
MN: 2007 Fall Meeting