Semi-Empirical Approach and Radar Polarimetry for Vegetation Observation
DLR German Aerospace Center,
PO Box 1116,
The health of crop depends on the amount of supplies on one hand and the exhalation of crop specific parameters on other hand. Important parameters in crop development are crop height, leaf area index, crop covered soil moisture etc. Valuating these parameters over large area is difficult physically, but it has its importance in the crop-physiology research and for instant health of a crop. Remote sensing can provide information on the actual status of vegetation. In this direction, radar has proved to have some inherent advantages over optical sensors in crop monitoring due to the ability o microwaves to penetrate into/and through the vegetaton cover. Many studies have been carried out to investigate the sensitivity of microwave sensors to agricultural vegetation parameters and promissing results have been obtained. Until now polarimetric-interferometric approaches have been mainly applyed on forests to assess the tree height and extinction coefficient. This papers highlights the semi-empirical polarimetric / interferometric approach to estimate agricultural vegetation parameters. The effect of crop height on the backscattering coefficient and interferometric observables for various polarizations is analysed as well as the sensitivity to vegetation extinction coefficient. Based on this the potential of polarimetric / interferometric observables for quantitative crop parameter estimation is discussed.