Estimation of Dielectric Constant Using A Dual-pol Sentinel-1A in Tropical Peatland

Abstract Synthetic Aperture Radar (SAR) is newest remote sensing technology that is not affected by meteorological conditions. This technology is particularly suitable for use in tropical regions such as Indonesia. In tropical peatland, Indonesia becomes the most important countries for peat areas and carbon stocks. However, this tropical peatland forest had been disturbed by fires, and become a national issue and an international issue. In disaster mitigation, identifying the existence of tropical peatland are needed. But this information is very limited. Therefore, we analysed backscattering value of VV and VH polarisation, and estimated dielectric constant from a dual-polarisation Sentinel-1A in Siak Regency, Riau Province, Indonesia. We also measured dielectric constant at four several types of land use (namely, forest, oil palm, shrubs, and agriculture) along with two types of peat conditions. Results indicated that the dielectric constant decreases as the land use become dry. Results show that the profiles of dielectric constant derived from dual-pol Sentinel-1A images have a high similarity to the direct approach using GPR, with a degree of similarity of 87.24%. The averaged dielectric constants of peat are lower than the peat in subtropics area and ranges between 41 and 68.