Role of organic matter in obliterating the effects of iron on spectral reflectance and colour of Brazilian tropical soils

Galvão, Lênio Soares; Vitorello, Ícaro

doi:10.1080/014311698215090

Cited by 88 publications

(57 citation statements)

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“…The negative r values were consistent with the soil spectral properties described in the literature (Stoner & Baumgardner, 1981;Formaggio et al, 1996;Galvão & Vitorello, 1998;Demattê et al, 2004;Dalmolin et al, 2005). Regression relationships were applied to the exposed soil image resulting from the use of the spectral mixture model and of the normalized SWIR and TIR approach to show variations in soil constituents (e.g., Al 2 O 3 ) on a per-pixel basis (Figure 7).…”

Section: Possibilities Of Estimating Soil Constituents Using Aster Resupporting

confidence: 54%

“…Despite these advantages, the number of soil investigations using this sensor is still very small when compared with Landsat or VNIR-SWIR laboratory sensor studies to describe the effects of soil constituents (e.g., organic matter, Fe oxides and clay minerals) on reflectance (Stoner & Baumgardner, 1981;Formaggio et al, 1996;Galvão & Vitorello, 1998;Demattê et al, 2004;Dalmolin et al, 2005 and references therein). On the other hand, the relationships between soil granulometric-chemical properties and emissivity data are not completely characterized, even in laboratory studies in the TIR spectral region.…”

Section: Introductionmentioning

confidence: 99%

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The combined use of reflectance, emissivity and elevation Aster/Terra data for tropical soil studies

Breunig

Galvão

Formaggio

et al. 2009

Rev. Bras. Ciênc. Solo

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SUMMARYReflectance, emissivity and elevation data of the sensor ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer)/Terra were used to characterize soil composition variations according to the toposequence position. Normalized data of SWIR (shortwave infrared) reflectance and TIR (thermal infrared) emissivity, coupled to a soil-fraction image from a spectral mixture model, were evaluated to separate bare soils from nonphotosynthetic vegetation. Regression relationships of some soil properties with reflectance and emissivity data were then applied on the exposed soil pixels. The resulting estimated values were plotted on the ASTER-derived digital elevation model. Results showed that the SWIR bands 5 and 6 and the TIR bands 10 and 14 measured the clay mineral absorption band and the quartz emissivity feature, respectively. These bands improved also the discrimination between nonphotosynthetic vegetation and soils. Despite the differences in pixel size and field sampling size, some soil properties were correlated with reflectance (R 2 of 0.65 for Al 2 O 3 in band 6; 0.61 for Fe 2 O 3 in band 3) and emissivity (R 2 of 0.65 for total sand fraction in the 10/14 band ratio). The combined use of reflectance, emissivity and elevation data revealed variations in soil composition with topography in specific parts of the landscape. From higher to lower slope positions, a general decrease in Al 2 O 3 and increase in total sand fraction was observed, due to the prevalence of Rhodic Acrustox at the top and its gradual transition to Typic Acrustox at the bottom.

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Section: Possibilities Of Estimating Soil Constituents Using Aster Resupporting

confidence: 54%

Section: Introductionmentioning

confidence: 99%

The combined use of reflectance, emissivity and elevation Aster/Terra data for tropical soil studies

Breunig

Galvão

Formaggio

et al. 2009

Rev. Bras. Ciênc. Solo

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“…Exemplos da aplicação do sensoriamento remoto na ciência do solo podem ser verificados em alguns trabalhos, como os de Madeira Netto et al (1997), Galvão & Vitorelo (1998) e Demattê & Garcia (1999).…”

Section: Introductionunclassified

Determinação indireta do teor de hematita no solo a partir de dados de colorimetria e radiometria

Campos

Demattê²,

Quartaroli³

2003

Pesq. agropec. bras.

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A cor do solo é uma propriedade que deriva de alguns atributos do próprio solo, entre eles, do teor de óxidos de ferro. Desse modo, o estabelecimento de relações funcionais entre dados referentes à caracterização da cor e teores de óxidos de ferro apresenta-se como uma alternativa simples e rápida para a semiquantificação dos teores dos referidos óxidos. O objetivo do presente trabalho foi semiquantificar os teores de hematita na fração argila, em laboratório, a partir da avaliação automatizada das cores de amostras de solos do Estado de São Paulo, utilizando um colorímetro e um espectrorradiômetro. Os dados obtidos por radiometria serviram de base para a determinação da cor nos sistemas L*a*b* e Munsell, bem como para o cálculo de índices de avermelhamento (IAVs). Os IAVs apresentaram dependência funcional dos teores de hematita e foram as melhores relações verificadas com os índices determinados a partir de cores no sistema L*a*b*. Modelos exponenciais, baseados em dados obtidos por sensores, mostram-se adequados na predição dos teores de hematita.

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“…Another important fact that determines the shape and depth of the absorption band and, hence, impacts on the IFD are grain size and the presence of other iron-bearing minerals [21]. The presence of organic matter is also able to mask the iron absorption band at 900 nm [55].…”

Section: Rustenburgmentioning

confidence: 99%

Spaceborne Mine Waste Mineralogy Monitoring in South Africa, Applications for Modern Push-Broom Missions: Hyperion/OLI and EnMAP/Sentinel-2

et al. 2014

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Abstract:Remote sensing analysis is a crucial tool for monitoring the extent of mine waste surfaces and their mineralogy in countries with a long mining history, such as South Africa, where gold and platinum have been produced for over 90 years. These mine waste sites have the potential to contain problematic trace element species (e.g., U, Pb, Cr). In our research, we aim to combine the mapping and monitoring capacities of multispectral and hyperspectral spaceborne sensors. This is done to assess the potential of existing multispectral and hyperspectral spaceborne sensors (OLI and Hyperion) and future missions, such as Sentinel-2 and EnMAP (Environmental Mapping and Analysis Program), for mapping the spatial extent of these mine waste surfaces. For this task we propose a new index, termed the iron feature depth (IFD), derived from Landsat-8 OLI data to map the 900-nm absorption feature as a potential proxy for monitoring the spatial extent of mine waste. OLI was chosen, because it represents the most suitable sensor to map the IFD over large areas in a multi-temporal manner due to its spectral band layout; its (183 km × 170 km) scene size and its revisiting time of 16 days. The IFD is in good agreement with primary OPEN ACCESS Remote Sens. 2014, 6 6791 and secondary iron-bearing minerals mapped by the Material Identification and Characterization Algorithm (MICA) from EO-1 Hyperion data and illustrates that a combination of hyperspectral data (EnMAP) for mineral identification with multispectral data (Sentinel-2) for repetitive area-wide mapping and monitoring of the IFD as mine waste proxy is a promising application for future spaceborne sensors. A maximum, absolute model error is used to assess the ability of existing and future multispectral sensors to characterize mine waste via its 900-nm iron absorption feature. The following sensor-signal similarity ranking can be established for spectra from gold mining material: EnMAP 100% similarity to the reference, ALI 97.5%, Sentinel-2 97%, OLI and ASTER 95% and ETM+ 91% similarity.

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Role of organic matter in obliterating the effects of iron on spectral reflectance and colour of Brazilian tropical soils

Cited by 88 publications

References 0 publications

The combined use of reflectance, emissivity and elevation Aster/Terra data for tropical soil studies

The combined use of reflectance, emissivity and elevation Aster/Terra data for tropical soil studies

Determinação indireta do teor de hematita no solo a partir de dados de colorimetria e radiometria

Spaceborne Mine Waste Mineralogy Monitoring in South Africa, Applications for Modern Push-Broom Missions: Hyperion/OLI and EnMAP/Sentinel-2

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