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IEEE Transactions on Geoscience and Remote Sensing 48, 5 (2010) 2367 - 2374
Numerical Backscattering Analysis for Rough Surfaces Including a Cloddy Structure
Mehrez Zribi 1, Aurélie Le Morvan-Quemener 2, Monique Dechambre 3, 4, N. Baghdadi 5
(2010)

In recent years, the presence of a new type of agricultural-surface tillage used for the sowing of wheat and corn has been observed with increasing frequency. It illustrates less roughly ploughed soils, with a greater quantity of small clods distributed over the soil surface. In this paper, a new description of such rough agricultural surfaces is proposed. It is based on a composite model, including a classical surface represented by an exponential correlation function, together with a random cloddy structure. This description enables volumetric structures to be introduced over the soil's surface. A numerical moment-modeling method, based on integral equations, is used to evaluate the contribution of clods to the radar backscattering behavior of agricultural surfaces. It is found that the presence of clods explains the very small correlation lengths which are often found in cloddy agricultural fields. The classical approach, in which the surface is described by a correlation function only based on two statistical parameters, rms height and correlation length, overestimates the backscattering coefficients when compared with an approach that includes the clods. This overestimation is often observed with real radar data for such fields.
1 :  Centre d'études spatiales de la biosphère (CESBIO)
CNRS : UMR5126 – Institut de recherche pour le développement [IRD] – CNES – Observatoire Midi-Pyrénées – INSU – Université Paul Sabatier [UPS] - Toulouse III
2 :  Laboratoire inter-universitaire des systèmes atmosphèriques (LISA)
CNRS : UMR7583 – INSU – Université Paris VII - Paris Diderot – Université Paris-Est Créteil Val-de-Marne (UPEC)
3 :  Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS)
CNRS : UMR8190 – Université Pierre et Marie Curie [UPMC] - Paris VI – Université de Versailles Saint-Quentin-en-Yvelines – INSU
4 :  Institut Pierre-Simon-Laplace (IPSL)
CNRS : FR636 – Institut de recherche pour le développement [IRD] – CEA – CNES – INSU – Université Pierre et Marie Curie [UPMC] - Paris VI – Université de Versailles Saint-Quentin-en-Yvelines – Ecole normale supérieure de Paris - ENS Paris
5 :  Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD)
Centre de coopération internationale en recherche agronomique pour le développement [CIRAD]
Sciences de l'ingénieur/Electromagnétisme

Planète et Univers/Sciences de la Terre

Sciences du Vivant/Sciences agricoles