KAJIAN PEMANFAATAN DATA ALOSPALSAR DALAM PEMETAAN KELEMBABAN TANAH

Abstract

Soil moisture mapping has important role in the aspects of hydrology, meteorology, and agriculture. Hence, development of practical, efficient and reliable method for identification of soil moisture content in wide area is strongly required. In this study, identification of soil moisture using microwave remote sensing data was examined. Distribution ofsoil moisturemay indicatethe nature ofthe existingsurface. The objectives of this study are to investigate the application of two polarizations(VV and HH)of polarimetric-ALOS PALSAR data for soil moisture mapping and tostudy the characteristic of backscatter and dielectric constant for several land covers in Bekasi Regency and its vicinity. The soil moisture (mv) was mapped using the equation of Top et al. (1980) that used the variable of dielectric constant (ε') value, while the dielectric constant was calculated using equation developed by Dubois et al. (1995). The study results show that ALOS-PALSAR polarimetric is identified to be very good estimator for soil moisture mapping. At 0-5 cm soil depth, the average of soil moisture (% volume)value for vegetated land, fallow (bera) land, bare land, and built-up area are 25%, 20%, 24.9%, and 23.7% respectively. For surface that has higher moisture content, the backscatter value of VV polarization is more sensitive than HH polarization.The higher dielectric constant exhibit the higher soil moisture content. Surface roughness would also affect estimation accuracy of soil moisture.