INTEGRATION OF BIOMETRIC AND REMOTE SENSING TECHNIQUES FOR ESTIMATION OF NET ECOSYTEM PRODUCTIVITY IN TROPICAL RAIN FOREST

摘要

Biometric and remote sensing techniques are two different measurement methods that can be employed in estimating terrestrial carbon cycling from plot and can be extended to local or regional scales. Biometric technique is commonly referred to the observation of plot scale to the individual tree biomass in forested area that generally covered an area not exceeding 60 hectares. Recent advance technology, remote sensing technique is a satellite based measurement that can be used to map forest components as temporally, spectrally and spatially over large coverage area. In high dense vegetated area such as tropical rain forest, integration of biometric and remote sensing techniques seems as a new coming-up technique that enable to provide a significant terrestrial ecosystem model from combination of two different scales in determination of carbon source and sink. Thus in this study, integration from biometric and remote sensing techniques have been employed to estimate net ecosystem productivity (NEP) in Pasoh Forest Reserve (PFR), Peninsular Malaysia. Inventories to the series census data conducted by Forest Research Institute Malaysia (FRIM) have be used to calculate aboveground net primary productivity (NPP) from 2000 to 2005 based to the biometric technique. Instead, Moderate Resolution Imaging Spectroradiometer (MODIS) images using three spectral different bands; visible band, near infra-red band, ocean bands (band 11 and band 12) have been utilized to estimate NPP using "continuous field model". Six years of NPP results from both techniques and soil respiration have been analyzed using matrices least square method in order to determine integration coefficients. As a result, a new model NEP from integration of biometric and remote sensing techniques for tropical rain forest has been successfully produced in this study. As conclusion, the pattern of annual carbon sequestration at PFR is determined as carbon sink (+ve) during 2000 and 2001 at 4.609 t ha~(-1) yr~(-1) and 1.390 t ha~(-1) yr~(-1), respectively. Nonetheless, this study is also indicating PFR as carbon source (-ve) during 2002, 2003, 2004 and 2005 at 0.898 t ha~(-1) yr~(-1), -2.772 t ha~(-1) yr~(-1), -4.456 t ha~(-1) yr~(-1) and -6.077 t ha~(-1) yr~(-1), respectively.