Estimating Carbon Pool and Carbon Release due to Tropical Deforestation Using High-resolution Satellite Data: Carbon Release due to Tropical Deforestation
Forest-cover in the tropics is changing rapidly due to indiscriminate removal of timber from many localities. The main focus of the study is to develop an operational tool for monitoring biomass and carbon pool of tropical forest ecosystems. The method was applied to a test site of Bangladesh. The research used Landsat ETM+, Landsat TM and IRS pan images of 2001, 1992 and 1999 respectively. Geometrically corrected Landsat ETM+ imagery was obtained from USGS and adjusted to the field using GPS. Historical images were corrected using image-to-image registration. Atmospheric correction was done by modified dark object subtraction method. Stratified sampling design based on the remote sensing image was applied for assessing the above-ground biomass and carbon content of the study area. Field sampling was done during 2002-2003. Dbh and height of all the trees inside the sample plots were measured. Field measurement was finally converted to carbon content using allometric relations. Three different methods: stratification, regression and k-nearest neighbors were tested for combining remote sensing image information and field-based terrestrial carbon pool. Additional field sampling was conducted during 2003-2004 for testing the accuracy. Finally regression method was selected. The amount of carbon released and sequestrated from the ecosystem was estimated. The application of the developed method would be quite useful for understating the terrestrial carbon dynamics and global climate change
