Detection of Dry-Flammable Peatland Area by Using Backscattering Coefficient Information of ALOS-2 Data L-Band Frequency

Abstract

Forest fire is the main problem in Indonesia and 75% occurred in peatland area, mainly in open area. Fast-growing commercial oil palm and paper pulp tree plantations, especially in Sumatera and Kalimantan has led to widespread deforestation and drainage in peatland area. Therefore, detection of dry-flammable peatland area is important to support land and forest fires prevention. The purpose of this research is to develop simple model for detection of dry-flammable peatland area by using Synthetic Aperture Radar (SAR) ALOS-2 L-Band data. Synthetic Aperture Radar ALOS-2 operating in L-Band frequency have advantages for peatland monitoring compare to other radar satellite data due to its longest wavelength and higher resolution which made a possibility to penetrate peatland surface. In this research, statistic approach was used to calculate relationship and develop model between backscattering coefficient (BC) and groundwater table (GWT). The study area is located in Sungai Apit, Siak Regency, Riau Province, Indonesia. The GWT were measured from 18 points sampling. Backscattering coefficient then calculated based on ALOS-2 L-Band calibration from JAXA for level 1.1.(Single Look Complex) data. Based on this research, the result of the relationship between GWT and backscattering coefficient is −0.5 both for HH and VV polarization. The equation model were developed by using linear regression based on the relationship between GWT and backscattering coefficient of HH and VV polarization. By using the information of backscattering coefficient of HH and VV polarization, we can calculate GWT of the peatland area. GWT more than 40 cm is classify as dry-flammable peatland area. We have termed the model Simple Dry-Flammable Peatland Detection SAR Model.