Retrieving vegetation cover types in the complex natural ecosystem of the Pollino National Park (South Italy) from Hyperion data

摘要

In this paper the potential of the Hyperion spacebome hyperspectral data in discriminating land covers in complex natural ecosystems was evaluated according to the hierarchical structure of the European standard legend (CORINE Land Cover 2000). Furthermore, the ability of the Hyperion data in retrieving land cover information at sub-pixel level was assessed by exploiting the vegetation classes' distribution as obtained by aerial-photos. Four standard supervised classifiers have been compared in terms of algorithm performance and class accuracy by applying statistical metric; the best results were achieved with the Minimum Distance (MD) classifier. In those areas exhibiting mixed pixels at the Hyperion spatial resolution a Linear Spectral Unmixing technique was applied for deriving abundance fractions of the endmembers (i.e. land covers) previously identified. Accuracy of the unmixing analysis was evaluated using a Residual Error index calculated by relating Hyperion fractional abundances and reference aerial-photos. Results show the capability of Hyperion data to map land covers and vegetation diversity even at sub-pixel level within a complex natural landscape.