Monday, August 6, 2007 - 1:30 PM

OOS 5-1: Research and management issues associated with land-cover and land-use changes in the Great Basin

Jeanne C. Chambers, USDA Forest Service

The Great Basin is considered one of the most imperiled ecoregions in the United States.  The human population of the Great Basin is growing at one of the highest rates in the nation.  Land uses including road development and use, recreation, mining, energy development, conversion to agriculture, to urban use, and to non-native livestock forage, and especially intensive livestock grazing, have caused widespread degradation.  Sagebrush ecosystems, the dominant ecosystems in the region, are undergoing large-scale vegetation type conversions that are placing many sagebrush obligate species, like sage grouse, at risk.  Decreased fire frequency, overgrazing, and climate change have facilitated expansion of pinyon and juniper in the woodland zone resulting in elimination of understory sagebrush species and greater risk of high-severity crown fires.  Increases in annual invasive grasses, like Bromus tectorum, coupled with higher fire frequencies in low to mid-elevation ecosystems are resulting in progressive conversion to homogenous annual grasslands.  Changes in the watersheds because of ongoing land uses and vegetation type conversions as well as climate change and water diversions have resulted in stream incision and degradation of riparian ecosystems.  Challenges facing researchers and managers in the Great Basin given ongoing climate, land use and land cover changes include developing 1) the necessary understanding of ecosystem trajectories and alternative futures, and 2) effective strategies for prioritizing conservation and restoration efforts and implementing other management activities.  Maintaining sustainable ecosystems will require a comprehensive approach that includes regional scales appropriate for addressing the many urgent problems in the Great Basin.