Preparation Methods for Estimating Value of Radiation Absorption by Using Landsat TM / ETM + (A case study of Mount Forest Walat Sukabumi).

Abstract

The purpose of this study is to predict the short-wave radiation values which is absorbed by using Landsat ETM + satellite imagery and software Gap Light Analyzer (GLA). Equilibrium radiation at the forest vegetation is ρ + τ + α = 1, where α is the proportion of solar radiation flux density absorbed by unit leaf area index, ρ is the proportion of flux density solar radiation reflected by a unit of leaf area index or canopy, and τ is proportion of solar radiation flux density transmitted by the unit leaf area index (Impron, 1999). The amount of transmission and reflection depending on the angle of solar radiation (Monteith, 1972). Radiation values components in Walat Mount Forest is short wave radiation value of 48 Wm-2, the transmission value is obtained by using the formula ρ + τ + α = 100% value of 89 Wm-2, and transmission value using the GLA is 100 Wm-2. Radiation absorption value in Walat Mountain is obtained using two methods, the first method is obtained using Kirchoff law approach of radiation absorption which value of 388 Wm-2 and the second is using the GLA which value of 377 Wm-2.