Study Locations

GBEM-Team Leader

   -Jeanne Chambers

EPR-Project Leader

   -Robin Tausch

The Book

   -Great Basin Riparian Ecosystems

GBEM-Field Tour

Employment

The project is located in the Shoshone, Toiyabe, Toquima, and Monitor Mountain Ranges and is in the center of the hydrologic Great Basin, an area comprised of a series of basins and ranges with no drainage to the sea. The mountain ranges are typical north-south, fault-blocked ranges with complex structural geology. Watershed elevations range from about 3200 m at the top of the watersheds to 1850 m at the bases. Land management frequently changes at the base of the mountains from Forest Service to Bureau of Land Management.

Because of the large elevational gradients, precipitation and temperature regimes vary significantly from the tops to the bottoms of the watersheds. In this semi-arid region, precipitation approaches 45 cm at the tops of the watersheds and drops to as little as 20 cm at the bases. At the town site of Austin, Nevada, the only long-term weather station in the area, annual average precipitation is 31 cm. Most precipitation arrives during the winter as snow, and peak runoff and most flood events occur during snowmelt in late May and June. Despite this, convective summer storms can result in significant runoff and erosion. The stream systems typically occur within narrow valleys and are high gradient, coarse-grained, and often highly incised. While low flows in these stream systems range from about 0.015 to 0.063 m3 s, high flows range from 0.214 to 0.683 m3 s.

Vegetation changes significantly along the elevational gradient. Valley floors are often characterized by salt desert vegetation, including Atriplex confertifolia and Ceratoides lanata. At low to middle elevations, Wyoming big sagebrush (Artemisia tridentata spp. wyomingensis) communities commingle with singleleaf pinyon (Pinyon monophylla) and Utah juniper (Juniperous osteosperma) woodlands. At higher elevations, mountain big sagebrush Artemisia tridentata spp. vaseyana communities and limber pine Pinus flexilis dominate. Riparian vegetation consists of narrow stringers of quaking aspen (Populus tremuloides), willow (spp.), and herbaceous communities. A detailed ecological type classification has been developed for the central Nevada riparian ecosystems that is based on the physical and hydrological characteristics of the type, key soil attributes. and vegetation species composition (USDA Forest Service, Intermountain Region, R4-ECOL-96-01, 1996). A broader scale classification of Humboldt and Toiyabe National Forest riparian areas is also in existence (USDA Forest Service, Intermountain Region, 1992).