<?xml version="1.0"?>
<oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:title>Field-scale spatial correlation between soil and Vis-NIR spectra in the Cerrado biome of Central Brazil</dc:title>
  <dc:creator>de Oliveira, J. F.</dc:creator>
  <dc:creator>/Brossard, Michel</dc:creator>
  <dc:creator>Corazza, E. J.</dc:creator>
  <dc:creator>Guimaraes, M. D.</dc:creator>
  <dc:creator>Marchao, R. L.</dc:creator>
  <dc:subject>Ki and K r indexes</dc:subject>
  <dc:subject>Reflectance inflection difference</dc:subject>
  <dc:subject>Soil spatial variability</dc:subject>
  <dc:subject>Soil spectra</dc:subject>
  <dc:description>Visible and near-infrared (Vis-NIR) spectroscopy is a tool to determine soi l spatial variability and has been used to map soils and their properties. Considering that physical , chemical , mineralogical , and morphological soi l properties can affect the intensity and the depth of the spectral reflectance band in the Vis-NIR region, the objectives of this work were to: (i) evaluate the potential of the reflectance inflection difference (RID) to discriminate soils; and (ii) veri f y potential spatial correlations of the RID with soi l properties, compared with the f u l l spectra, in order to build thematic maps at a fiel d scale. In a farm of 375 ha, 78 soil samples from the 0.87-0.92-m depth were collected in a regular grid of 200 m, with a focus on the soi l diagnostic horizon (Bw horizon). The sampled soils were a Latossolo Vermelho-Amarelo &amp; PRIME;acrico (Haplic Ferralsol) and a Latossolo Ver-melho distr &amp; PRIME;ofico (Rhodic Ferralsol). Twenty-two physical , chemical , mineralogical , and morphological soi l properties were determined, and the Vis-NIR spectra between 400 and 2500 nm were measured. Considering the presence of an inflection band and its relationship with soi l properties, the spectral bands used to calculate the RID were between (base 1/base 2): 400-510, 730-930, 1290-1450, 1800-1950, 2000-2218, and 2218-2290 nm. The RID failed to map the spatial variability of soi l properties, with a Kappa inde x of 39%; therefore, it is not a good parameter for building thematic maps of soi l parameters. In addition, the complete spectru m (mainly in 400-510, 730-930, 1290-1450, 1800-1950, 2000-2218, and 2218-2290 nm) was better spatially correlated with soi l properties than the decomposition of the spectrum by the RID. Soi l classification and level of dis-cretization as affected by spectral variability were also discussed here. Three soi l groups were discriminated mainly by the Ki and K r indexes and clay content. Moreover, the variability of the spectra was conditioned by the spatial variability of the mentioned variables. The clay content for soils with a discrepant particle size (group 1 compared with groups 2 and 3) and the Ki and K r indexes for soils with a homogeneous particle size (between groups 2 and 3), associated with the f u l l Vis-NIR spectral analysis, allowed building thematic maps with a good precision, without the need of mathematical models; this was possible by the modification of the reflectance intensity and the size of the concavity of the spectral band.</dc:description>
  <dc:date>2022</dc:date>
  <dc:type>text</dc:type>
  <dc:identifier>https://www.documentation.ird.fr/hor/fdi:010085332</dc:identifier>
  <dc:identifier>fdi:010085332</dc:identifier>
  <dc:identifier>de Oliveira J. F., Brossard Michel, Corazza E. J., Guimaraes M. D., Marchao R. L.. Field-scale spatial correlation between soil and Vis-NIR spectra in the Cerrado biome of Central Brazil. 2022, 30, e00532 [13 ]</dc:identifier>
  <dc:language>EN</dc:language>
  <dc:coverage>BRESIL</dc:coverage>
  <dc:coverage>GOIAS</dc:coverage>
</oai_dc:dc>
