Title :
On the characterization of agricultural soil roughness for radar remote sensing studies
Author :
Davidson, Malcolm W J ; Le Toan, Thuy ; Mattia, Francesco ; Satalino, Giuseppe ; Manninen, Terhikki ; Borgeaud, Maurice
Author_Institution :
Centre d´´Etudes de la Biosphere, Toulouse, France
fDate :
3/1/2000 12:00:00 AM
Abstract :
The surface roughness parameters commonly used as inputs to electromagnetic surface scattering models (SPM, PO, GO, and IEM) are the root mean square (RMS) height s, and autocorrelation length l. However, soil moisture retrieval studies based on these models have yielded inconsistent results, not so much because of the failure of the models themselves, but because of the complexity of natural surfaces and the difficulty in estimating appropriate input roughness parameters. In this paper, the authors address the issue of soil roughness characterization in the case of agricultural fields having different tillage (roughness) states by making use of an extensive multisite database of surface profiles collected using a novel laser profiler capable of recording profiles up to 25 m long. Using this dataset, the range of RMS height and correlation values associated with each agricultural roughness state is estimated, and the dependence of these estimates on profile length is investigated. The results show that at spatial scales equivalent to those of the SAR resolution cell, agricultural surface roughness characteristics are well described by the superposition of a single scale process related to the tillage state with a multiscale random fractal process related to field topography.
Keywords :
agriculture; backscatter; fractals; geophysical techniques; radar cross-sections; radar theory; remote sensing by radar; rough surfaces; soil; synthetic aperture radar; terrain mapping; SAR; agricultural field; agricultural soil roughness; autocorrelation length; backscatter; characterization; electromagnetic surface scattering model; geophysical measurement technique; land surface; multiscale random fractal; natural surface; radar remote sensing; radar scattering; rough surface; superposition; surface profile; surface roughness parameters; terrain mapping; tillage; Electromagnetic modeling; Electromagnetic scattering; Radar scattering; Rough surfaces; Scanning probe microscopy; Scattering parameters; Soil; State estimation; Surface roughness; Surface topography;
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on