Some spectral considerations for remote sensing of soil salinity

Abstract

The National Soil Conservation Program (NSCP) and CSIRO funded a research project titled Remote Sensing of Agricultural Salinity, which gathered field and airborne reflectance data for study sites in areas of dryland agricultural salinity in Western Australia. Multivariate techniques are employed to analyse these data gathered over a 3-year period to determine optimum, spectral and temporal considerations for maximizing information content. This report concentrates on some of the spectral aspects and concludes that: spectral bands, existing in currently available remote sensing systems, may not be optimal for the delineation of salinity; that volunteer vegetation indicated the impact of increasing salinity; and that minor amounts of soluble salts in surface soils will modify spectra. The usefulness of portable field spectroradiometers and airborne scanning systems are also assessed for the discrimination of areas of land in the early stages of the effects of salinization.