Balance of emissions with greenhouse effect in silvopastoral systems in three life zones of Costa Rica

摘要

The greenhouse effect is the result of the gases accumulation in the atmosphere, mainly carbon dioxide (CO_2), methane (CBU) and nitrous oxide (N_2O), that they increase annually 0.5, 0.6 and 0.35% respectively. Approximately 30% of these gases take place for the change in the use of the soil. It is considered that the tropics emit of 10 to 30 million of carbon (C) year~(-1) as a result of decreasing of the organic matter in the soils deforested (Detwiller and Hall 1988). In this sense, the soils with pastures play a very important roll for the great extension that they cover, for the retention and reduction of the emission of C to the atmosphere (Minarni et al. 1993, Fischer et al. 1994).