Estimation of yellow starthistle abundance through CASI-2 hyperspectral imagery using linear spectral mixture models
The invasive weed yellow starthistle (Centaurea solstitialis) has infested between 4 and 6 million hectares in California. It often forms dense infestations and rapidly depletes soil moisture, preventing the establishment of other species. Precise assessment of its canopy cover, especially low-density abundance in the earlier growing season, is the key to effective management. Compact Airborne Spectrographic Imager 2 (CASI-2) hyperspectral imagery was acquired at the western edge of California's Central Valley grasslands on July 15, 2003. Four linear spectral mixture models (LSMM) were investigated from the original CASI-2 data. Band selections based upon residual analysis and feature extraction (PCA) were further explored to reduce the data dimension. All approaches, except four band-selection unconstrained LSMMs, provide consistent results. The uncertainty of the PCA-based LSMM was estimated through a Monte-Carlo simulation. The maximum standard deviation was approximately 11%. The results suggest that unmixing CASI-2 imagery could be used for estimating and mapping yellow starthistle for larger regional areas.
hyperspectral, unmixing, invasive species
Miao, Xin, Peng Gong, Sarah Swope, Ruiliang Pu, Raymond Carruthers, Gerald L. Anderson, Jill S. Heaton, and C. R. Tracy. "Estimation of yellow starthistle abundance through CASI-2 hyperspectral imagery using linear spectral mixture models." Remote Sensing of Environment 101, no. 3 (2006): 329-341.
Remote Sensing of Environment