Spectral and biophysical relationships of montane sagebrush communities in multi-temporal SPOT XS data
Correlation and multiple regression analysis was used to examine the relationships between spectral and biotic factors within the sagebrush communities of Grand Teton National Park, Wyoming. Field-sampled data on biophysical factors were regressed against June 1996 and September 1996 SPOT multi-spectral reflectance data for fifty-one plots. Highest r2 values were generated for regression models using June reflectance data alone for predicting biophysical factors. Predictability of bitterbrush cover was improved using September reflectance data alone. Models predicting biophysical characteristics of sagebrush communities generally were not improved by using a combined June-September data set. Regression models for big sagebrush height, low sagebrush cover, and rock/soil cover were improved slightly using the combined two-date data set. Selection of remotely sensed data for biophysical studies of vegetation communities should be driven by the ecological and phenological characteristics of the vegetation community to be studied.