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Studies to identify gaps in the protection of habitat for species of concern have been inconclusive and ham- pered by single-scale or poor multi-scale sampling methods, large minimum mapping units (MMU?s of 2 ha to 100 ha), limited and subjectively selected field observations, and poor mathematical and ecological models. We overcome these obstacles with improved multi-scale sampling techniques, smaller MMU?s (< 0.02 ha), an unbiased sampling design based on double sampling, improved mathematical models including species-area curves corrected for habitat heterogeneity, and geographic information system-based ecological models. We apply this landscape analysis approach to address resource issues in Rocky Mountain...
This study identifies areas with ecosystem performance anomalies (EPA) within the Upper Colorado River Basin (UCRB) during 2005?2007 using satellite observations, climate data, and ecosystem models. The final EPA maps with 250-m spatial resolution were categorized as normal performance, underperformance, and overperformance (observed performance relative to weather-based predictions) at the 90% level of confidence. The EPA maps were validated using ?percentage of bare soil? ground observations. The validation results at locations with comparable site potential showed that regions identified as persistently underperforming (overperforming) tended to have a higher (lower) percentage of bare soil, suggesting that our...
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Among threats to the sagebrush ecosystem in the Great Basin and elsewhere (BLM 1999, 2002; Nachlinger et al. 2001; Wisdom et al. 2003) is the threat of displacement of native habitats by cheatgrass (Bromus tectorum). Mapping these threats in the sagebrush ecosystem will allow managers to identify areas of native vegetation at high risk of displacement, where active restoration may be required, versus areas at low risk, where conservation of existing habitats may be preferable. A draft model of risk of displacement of sagebrush and other native vegetation cover types by cheatgrass was applied to the 14 ecological provinces that intersect the Great Basin. The model was applied to sagebrush cover and other vegetation...
    map background search result map search result map Risk of Cheatgrass Displacement of Sagebrush and other Native Vegetation Risk of Cheatgrass Displacement of Sagebrush and other Native Vegetation