@Article{MoreiraTeixGalv:2015:PoMuHy,
author = "Moreira, L. C. J. and Teixeira, A. D. S. and Galv{\~a}o,
L{\^e}nio Soares",
affiliation = "{Universidade Federal do Cear{\'a} (UFC)} and {Universidade
Federal do Cear{\'a} (UFC)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Potential of multispectral and hyperspectral data to detect
saline-exposed soils in Brazil",
journal = "GIScience and Remote Sensing",
year = "2015",
volume = "52",
number = "4",
pages = "416--436",
month = "July",
keywords = "electrical conductivity, hyperion, hyperspectral, NDVI,
OLI/Landsat-8, soil salinity.",
abstract = "Irrigation-induced soil salinization is an important land
degradation process in northeastern Brazil. We used multispectral
and hyperspectral sensors to detect saline-exposed soils in an
area cultivated with irrigated rice. Spectral mixture analysis
(SMA) was applied to Operational Land Imager (OLI)/Landsat-8 data
to identify exposed soils. By measuring the electrical
conductivity (EC) of soil samples from 53 sites, we classified
them into saline and non-saline. The surface reflectance Thematic
Mapper /Landsat-5 product was used to inspect the normalized
difference vegetation index (NDVI) variations over time
(1984-2011) at the sites. Using OLI/Landsat-8 and Hyperion/Earth
Observing One, we obtained five salinity indices and scores from
principal component analysis applied to exposed soil pixels. These
indices along with the first principal component (PC1) were
regressed against EC to estimate soil salinization. Different
metrics and support vector machine (SVM) were tested to
discriminate saline and non-saline soils. The results showed that
exposed soils detected by SMA had NDVI with a lower mean and
standard deviation over time in the saline areas due to vegetation
growth limitation. NaCl absorption bands were not observed in the
Hyperion spectra due to atmospheric water vapor. Therefore, soil
salinity detected by OLI or Hyperion was due to soil brightness
rather than absorption bands. Because most salinity indices and
scores expressed brightness to some extent, they were correlated
with EC, especially the Salinity Index and PC1. However, compared
with OLI, the narrow-band salinity indices of Hyperion produced a
lower root mean square error for EC estimates, better
discrimination between saline and non-saline soils using the
Euclidean distance and spectral angle metrics, and higher SVM
classification accuracy.",
doi = "10.1080/15481603.2015.1040227",
url = "http://dx.doi.org/10.1080/15481603.2015.1040227",
issn = "1548-1603",
language = "en",
urlaccessdate = "27 abr. 2024"
}