@Article{GalvćoPonzLiesSant:2009:PoDiTr,
author = "Galv{\~a}o, L{\^e}nio Soares and Ponzoni, Fl{\'a}vio Jorge and
Liesenberg, Veraldo and Santos, Jo{\~a}o Roberto dos",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Possibilities of discriminating tropical secondary succession in
Amaz{\^o}nia using hyperspectral and multiangular CHRIS/PROBA
data",
journal = "International Journal of Applied Earth Observation and
Geoinformation",
year = "2009",
volume = "11",
number = "1",
pages = "8--14",
keywords = "Amaz{\^o}nia, CHRIS/PROBA, Hyperspectral, Multiangular, Secondary
succession.",
abstract = "CHRIS/PROBA data collected in the Brazilian Amaz{\^o}nia in 4
view angles (-36°, nadir, +36°, +55°) and 62 bands (410-1000 nm
range) were evaluated for the discrimination between primary
forest and 3 stages of secondary succession after deforestation:
initial (SS1; <5 years), intermediate (SS2; 5-15 years) and
advanced (SS3; >15 years). Single view angle and multiangular
approaches (nadir plus anisotropic information derived from
reflectance ratios between view angles) were tested for
discrimination. Both approaches used principal components analysis
(PCA) applied to pixel spectra representative of each class in
order to reduce data dimensionality at each dataset, to enhance
separability between the classes, and to provide input variables
for multiple discriminant analysis (MDA). The results showed that
the off-nadir viewing improved discrimination between the
successional stages. Discrimination between SS2 and SS3 was
enhanced with PCA at +36° view angle. Primary forest and SS3
presented a more anisotropic behavior than SS2 and SS1, especially
in the backward scattering direction (positive view angles) in
which great amounts of sunlit canopy components were viewed by the
sensor. MDA classification results showed that the multiangular
approach produced an overall improvement in the discrimination.
From the single (nadir) to the multiangular approach,
classification accuracy using a separate set of pixels increased
from 83.3% to 98.3% for SS1, 53.3% to 70.0% for SS2, and 58.3% to
76.7% for SS3. The nadir and multiangular classifications were
statistically different at a 0.05% level of significance. Kappa
statistics increased from 0.63 to 0.82. The results showed that
multiangular data can improve the differentiation between primary
forest and old stages of natural vegetation regrowth, which have
been reported in the literature as the most difficult classes to
be mapped in the Amazonian environment.",
doi = "10.1016/j.jag.2008.04.001",
url = "http://dx.doi.org/10.1016/j.jag.2008.04.001",
issn = "0303-2434",
language = "en",
targetfile = "lenio1.pdf",
urlaccessdate = "27 abr. 2024"
}