A technique to estimate topsoil thickness in arid and semi-arid areas of north-eastern Jordan using synthetic aperture radar data

A Japanese Earth Resources Satellite (JERS)-1 L-band synthetic aperture radar (SAR) dataset was used for estimating topsoil thickness, of different types, in arid and semi-arid areas in north-eastern Jordan. In this research, the relationship between remotely sensed data, backscattering coefficient and the thickness of topsoil was investigated. Based on the dielectric constant properties of the topsoil samples, the relationship between the backscattering coefficient and the topsoil thickness was obtained by developing a multilayer modelling analysis. Using this model, the topsoil thickness had been estimated by means of the derived backscattering coefficients from JERS-1 SAR image. The estimated thickness values of the different topsoil types were found to be comparable with field ground data. The estimated minimum thickness for hardpan topsoil is 55 cm; Qaa topsoil, 74 cm; and topsoil of herbaceous area, 46 cm, while the estimated maximum thickness is more than 98 cm, more than 100 cm, and 82 cm, respectively. Ground data, on the other hand, revealed the minimum thickness for hardpan topsoil to be 50 cm; Qaa topsoil, 70 cm; and topsoil of herbaceous area, 40 cm, while the maximum thickness is more than 120 cm, more than 100 cm, and 80 cm, respectively.