期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2007
卷号：XXXVI-7/C50
出版社：Copernicus Publications
摘要：The discrete Anisotropic Radiative Transfer (DART) model, coupled with an adjusted version of the PROSPECT model, was used to retrieve total chlorophyll content (Cab) of a complex Norway spruce (Picea abies (L.) Karst.) canopy from airborne hyperspectral data acquired at very high spatial resolution. The radiative transfer models were parameterized by using field measurements and observations collected from a young spruce stand growing at the permanent experimental site Bíly K.í. (the Moravian-Silesian Beskydy Mts., the Czech Republic, 18.53863°E, 49.50256°N, 936 m a.s.l.). A set of the hyperspectral images with a pixel-size of 0.4 m was acquired for the test site by an airborne AISA Eagle VNIR system in September 18th, 2004. An operational canopy Cabestimation was carried out by means of a PROSPECT-DART inversion employing an artificial neural network (ANN) and a vegetation index ANCB650-720. Both retrieval approaches used continuum removed reflectance values of six AISA Eagle spectral bands located between 650 and 720 nm. The Cabinversion was only performed for direct sun exposed (sunlit) crown pixels in order to ensure a high quality (noiseless) reflectance signal. Results of both inversion approaches were similar, when validated against the ground measured Cabof nine Norway spruce crowns. Coefficients of determination (R2) between ground truth and remote sensing Cabestimates were 0.78 and 0.76, respectively, with root mean square errors (RMSE) of 2.95 μg cm-2for the ANN and 3.36 μg cm-2for the ANCB650-720retrieval. The spatial patterns of Cabvalues estimated by both inversion methods were consistent with each other. About 80% of the Cabestimated values had an absolute difference smaller than 2 μg cm
关键词：Remote Sensing; Hyperspectral; High Resolution; Forestry; Vegetation; Estimation; Retrieval; Neural
