Land cover mapping and carbon pools estimates in Rondonia, Brazil

In order to estimate changes in carbon pools and fluxes to the atmosphere, we used Landsat TM data to calculate the extent of areas converted to pasture to different lengths of time in a 100km by 92km area of the southwestern Brazilian Amazon. Image processing and the supervised classification allowed the production of an accurate land cover map including forest and pastures of different ages. Estimates of carbon pools and fluxes to the atmosphere were carried out using the results of Landsat image analysis and published data about carbon stocks in vegetation and soil. The results showed that a large amount of carbon (12 103 g cm2) is released after three years under pasture. From the initial burning and after fifth year under pasture, the system functioned as a source of CO2 to atmosphere. After this period the balance is slightly negative and the amount of CO2 released is lower than the amount released in the initial period.