Abstract
Plant water stress can limit productivity in both natural and agronomic plant communities. Short term as well as long term water stress has the same effects on plant physiology and canopy architecture. Changes in water status of a canopy can have indirect effects on remotely sensed optical reflectance and thermal emittance. The main aim of this study was to study the diurnal spectral response of sugar beet canopies, mainly in the near infrared region, with various environmental and structural properties under field conditions, through measurements taken in the laboratory and in the field, which include spectral data and biophysical variables. Results from this research indicated that the diurnal canopy reflectance varied for both non-stressed and stressed crops due to the effect of solar zenith angle. Overall, this work investigated the relationship between vegetation variables and reflectance of water stressed vegetation and showed that biophysical variables that affect canopy reflectance should be considered carefully in any attempt to implement remote sensing techniques. (Author)