A grazing gradient in Grand Staircase-Escalante National Monument, Utah was identified with field measurements and spectral mixture analysis (SMA) of remotely sensed hyperspectral imagery. Grazing gradient persistence during a period of above-average rainfall was confirmed using multi-temporal Landsat imagery. SMA revealed a clear trend of increasing photosynthetic vegetation (PV) and non-photosynthetic vegetation (NPV) and decreasing bare soil with distance from water. Results showed that on steeper slopes, fractional cover of PV and bare soil increased while NPV decreased. The fundamental relationship of changing cover fractions with distance from water was preserved within all slope classes. This imaging showed that the study area had undergone land degradation consistent with reports of overgrazing in this and similar regions, and that imaging spectroscopy can be used to assess rangeland condition by detecting fine scale variations in cover fractions known to be sensitive to grazing.
Citations and enhanced abstracts for journals articles and documents focused on rangeland ecology and management. RSIS is a collaboration between Montana State University, University of Idaho, and University of Wyoming.