Multifrequency Measurements of the Effects of Soil Moisture, Soil Texture, And Surface Roughness

Wang, James R.; O'Neill, Peggy E.; Jackson, Thomas J.; Engman, Edwin T.

doi:10.1109/tgrs.1983.350529

Cited by 207 publications

(87 citation statements)

References 18 publications

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“…Another parameter playing an important role in microwave emission from soils is the surface soil roughness, which causes an increase in emissivity and a reduction of the sensitivity to SMC, especially at the higher frequencies (Choudhury et al, 1979;Wang et al, 1983). The definition of roughness of a soil surface depends both on the surface characteristics and the observation wavelength.…”

Section: Microwave Remote Sensing Techniquesmentioning

confidence: 99%

Microwave radiometric measurements of soil moisture in Italy

Macelloni¹,

Paloscia²,

Pampaloni³

et al. 2003

Hydrol. Earth Syst. Sci.

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Within the framework of the MAP and RAPHAEL projects, airborne experimental campaigns were carried out by the IFAC group in 1999 and 2000, using a multifrequency microwave radiometer at L, C and X bands (1.4, 6.8 and 10 GHz). The aim of the experiments was to collect soil moisture and vegetation biomass information on agricultural areas to give reliable inputs to the hydrological models. It is well known that microwave emission from soil, mainly at L-band (1.4 GHz), is very well correlated to its moisture content. Two experimental areas in Italy were selected for this project: one was the Toce Valley, Domodossola, in 1999, and the other, the agricultural area of Cerbaia, close to Florence, where flights were performed in 2000. Measurements were carried out on bare soils, corn and wheat fields at different growth stages and on meadows. Ground data of soil moisture (SMC) were collected by other research teams involved in the experiments. From the analysis of the data sets, it has been confirmed that L-band is well related to the SMC of a rather deep soil layer, whereas C-band is sensitive to the surface SMC and is more affected by the presence of surface roughness and vegetation, especially at high incidence angles. An algorithm for the retrieval of soil moisture, based on the sensitivity to moisture of the brightness temperature at C-band, has been tested using the collected data set. The results of the algorithm, which is able to correct for the effect of vegetation by means of the polarisation index at X-band, have been compared with soil moisture measurements in the ground. Finally, the sensitivity of emission at different frequencies to the soil moisture profile was investigated. Experimental data sets were interpreted by using the Integral Equation Model (IEM) and the outputs of the model were used to train an artificial neural network to reproduce the soil moisture content at different depths.

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Section: Microwave Remote Sensing Techniquesmentioning

confidence: 99%

Microwave radiometric measurements of soil moisture in Italy

Macelloni¹,

Paloscia²,

Pampaloni³

et al. 2003

Hydrol. Earth Syst. Sci.

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“…This possible uncertainty in the measurements was pointed out in [24] when calibration of the microwave radiometers over a smooth water surface was described. It The brightness temperature sensitivity to the variation of the individual surface roughness parameters is illustrated in Figure 5, where the solid curves are the best fits to the data.…”

Section: -4mentioning

confidence: 95%

Calculations of the Microwave Brightness Temperature of Rough Soil Surfaces: Bare Field

Mo¹,

Schmugge

Wang

1987

IEEE Trans. Geosci. Remote Sensing

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“…Generally, the resistivity and permittivity of the rock are functions of the chemical composition, density, porosity, water saturation, in homogeneity, poly-crystallinity, rock lithology and component geometries, which in turn are related to the particle size distribution (or rock texture), rock bulk density, and shape of the rock particles. [2][3][4][5][6][7] However, it is difficult to confirm the exact contribution of each physical and petrological parameter to a sample's measured dielectric constant. Of all of these aspects, the most dominant factor affecting the dielectric permittivity of rock is its water saturation, including both bound and free water.…”

Section: Introductionmentioning

confidence: 99%

Dielectric Constant Properties of Tight Sandstone

Liu¹

2017

IPCSE

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This study stated dielectric properties of tight sandstone, which has porosity below 2%, and permeability below milli-Darcy. At this in-situs condition, the inter-pores are almost not connective, and throats are in micro-or nano-scale, so the electric conduction occupied weak position, but dielectric property predominated the current travelled through the rocks. Hence, the dielectric property is much significant characteristics should be investigated in order to better understand the electric mechanism of tight rocks. This paper illustrated the characteristics with experimental data from low to high frequency (Hz-kHz). Two parameters, resistivity and permittivity or dielectricity, were investigated with tight sandstone cores. The experiments were executed at room temperature (20˚C), the cores were injected into different content and salinity salt solution. The content, or say saturation of the solution in cores varied from 0-100% (in fact, completely salt solution) the salinity change from 0 (fresh water) to 1mg/mol. The experiment results showed that all of these two physical quantities, i.e. resistivity (R p ) and permittivity (Cp), have properties of frequency dispersion over the whole frequency range. Further analysis indicates that frequency dispersion of resistivity is relatively weak, but of dielectric, is much more obvious. That proved dielectric is more sensitive to saturation and salinity than resistivity, especially at low frequency. Two variables were introduced in order to describe the frequency dispersion properties D R and D C , which corresponded R p and C p respectively. D R and D C should indicate more detail account of the polarization and relaxation of components of tight sandstone cores, which will be further discussed in other paper.

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Multifrequency Measurements of the Effects of Soil Moisture, Soil Texture, And Surface Roughness

Cited by 207 publications

References 18 publications

Microwave radiometric measurements of soil moisture in Italy

Microwave radiometric measurements of soil moisture in Italy

Calculations of the Microwave Brightness Temperature of Rough Soil Surfaces: Bare Field

Dielectric Constant Properties of Tight Sandstone

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