Analysis of soil physical parameters and their influence on ERS-1 backscatter

Hydrological and ecological models on a local scale require information about the spatial distribution of soil moisture. This study was conducted to develop methods for information retrieval about spatial and temporal variability of soil moisture and influencing soil parameters using ERS-1 PRI SAR data. Six test sites in the land of Brandenburg, Germany, were chosen to measure soil moisture simultaneous to ERS-1 passes. Multitemporal analysis of the test sites demonstrated the sensitivity of backscatter to soil moisture. However, the correlation results were improved by multiple regression analysis including for bulk density (r ranging between 0.63 and 0.92). The qualitative assessment of the influence of surface random roughness on backscatter showed that the level of backscatter response depends on different surface roughness conditions. A grouping of soil moisture values in three classes depending on surface conditions results in a strong correlation coefficient (r ranging between 0.88 and 0.91)