ISPRS Archives XXXVIII-8/W3 Workshop Proceedings: Impact of Climate Change on Agriculture 300 STUDY FOR THE EFFECT OF SOIL MOISTURE CONTENT ON THE AGRICULTURAL VEGETATION USING ACTIVE MICROWAVE REMOTE SENSING

Dielectric constant values of the samples of soil of Alwar (at various moist states) have been calculated using wave guide cell method at a single microwave frequency 9.78 GHz at 33C. The Backscattering coefficients for rough and bare soil surfaces 0 soil σ are calculated by Small Perturbation Model (SPM). Fresnal reflectivity of the soil surfaces which is an input parameter for SPM is calculated using the values of dielectric constant of the soil (at different wetness) and observation angle as input parameters. The roughness of soil in SPM is characterized by RMS height and correlation length and isotropic Gaussian auto correlation function. The radar backscattering coefficient of vegetative soil surface is determined by water cloud model. The total back scattering coefficient is calculated adding the contribution of the vegetation, 0 veg σ and that of the modified effect of underlying soil. The effect of vegetation canopy on the backscattering from bare soil surface is modified by a parameter vegetation transmissivity τ. The present study reveals that radar backscattering coefficient for bare soil surface 0 soil σ and vegetative soil surface 0 pp σ has a respective correlation with SMC of the soil. Further, 0 soil σ and pp σ decrease as the angle of observation increases. [email protected]