Characterization of soil surface roughness from terrestrial laser scanner data

The surface roughness parameters commonly used as inputs to forest radar backscatter models are the root mean square heights (RMS) s and auto-correlation length l. These parameters were traditionally estimated from a one-dimensional surface profile with limited length. The complexity of natural surfaces makes it very difficult to explicitly describe the soil roughness. Terrestrial Laser Scanner (TLS) provides a new approach for the characterization of soil surface roughness. In this paper we address the issue of soil roughness characterization from terrestrial laser scanner data. The RMS height s was calculated using TLS data and compared with field measurements. The results showed that the proposed method can be used to make soil roughness measurement so long as the data sampling frequency was high enough. The relationship between required sampling frequency and the wave length of Microwaves was derived. In addition to the soil roughness parameters, a high resolution three dimensional digital elevation model (DEM) was constructed.