Radar and optical/thermal satellite data have already proven their potential to estimate surface SM and pedological maps are already used to establish drainage qualities of dominant soils. The hypothesis of this research is that satellite images will help identify very well and very poorly drained soils for an entire agricultural plain in a semi-arid environment, even during drought periods. In this context, the goal of this research is to investigate the potential of empirical relationships
between remotely sensed signals (radar backscatter or optical reflectance and thermal emission) and SM values measured at the field scale in order to produce maps of estimated SM, and to identify very well and very poorly drained areas, across an agricultural plain in a semi-arid region in Sardinia (Italy). The methodology is based on multiple
scale data collected from 2003 to 2009: ENVISAT ASAR (Advanced
Synthetic Aperture Radar), RADARSAT-2, and LANDSAT TM5 satellite
imagery from 2003 on; ground data collected at the field plot scale
from 2005 on; and pedological and other information from regional
maps.