Invasive Species Mapping in Hawaiian Rainforests Using Multi-Temporal Hyperion Spaceborne Imaging Spectroscopy

We evaluated the potential of multi-temporal Multiple Endmember Spectral Mixture Analysis (MESMA) of Earth Observing-1 Hyperion data for detection of invasive tree species in the montane rainforest area of the Hawaii Volcanoes National Park, Island of Hawaii. We observed a clear seasonal trend in invasive species detection success when unmixing results were cross-referenced to ground observations; with Kappa coefficients (indicating detection success, 0-1) ranging between 0.66 (summer) and 0.69 (winter) and 0.51-0.53 during seasonal transition periods. An increase of Kappa to 0.80 was observed when spectral features extracted from September, August and January were integrated into MESMA. Multi-temporal unmixing improved the detection success of invasive species because spectral information acquired over different portions of the growing season allowed us to capture species-specific phenology, thereby reducing spectral similarity among species.