Estimating water content from hyperspectral measurements for fire risk mapping

This paper shows the interest of laboratory hyperspectral measurements to estimate fuel moisture content for fire risk assessment. Measurements were obtained for two Mediterranean forest species over a controlled water stress experiment. The hyperspectral measurements were performed with a Specim camera, sensible to spectral reflectance from 900 to 1700 nm. We calculated the spectral correlation with variations in the moisture content, both for the camera raw bands as well as for those adjusted to the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. High correlation values were obtained for moisture content measurements and the Normalized Difference Water Index (NDWI), both for Q. suber (r=0.803 with the FMC and r=0.846 for EWT), and for the Q. robur (r=0.705 with the FMC and r=0.802 for EWT). Our work asserts that both parameters can be estimated with appropriate accuracy using satellite images.