Assessing interactions between crop biophysical parameters and X-band
backscattering using empirical data and model sensitivity analysis
Abstract
Active microwave remote sensing data at different frequencies can
provide crucial information on crop morphology and conditions, thus
effectively supporting agronomic management at different scales. In this
work, we used variance-based global sensitivity analysis (GSA) as a
quantitative framework for investigating the sensitivity of X-band
backscattering to agronomic and morphological features typical of two
different crops, maize and rice. To this end, we jointly exploited
empirical data on crop status and growth, high-resolution TerraSAR-X
data, and microwave radiative transfer model (RTM) simulations.
Phenology-informed simulations allowed us to quantify the contributions
of different scattering mechanisms for the two crops under varying
observation setups, to assess the sensitivity of X-band backscattering
to morpho-structural crop biophysical parameters (and their
interactions), and to evaluate the effects of crop biomass on
backscatter across growth stages.