Abstract
CO2 evolution rates from three different types of soil cover (clearcut or bare soil, floor of new generated jungle and floor of mature rubber stand) were measured under tropical conditions in We t-Malaysia. The soil CO2 released from the new generated jungle forest was about 90% higher than that of the mature rubber stand; rather low CO2 release rates were observed on the bare clearcut soil. This suggests a very poor biological and respiratory activity at the bare clearcut soil compared with the floors of the mature rubber stand and the new generated jungle.