ABSTRACT
This chapter explores information from existing studies that have measured changes to surface soil Carbon (C) stocks following the conversion of forest to pasture in the Brazilian Amazon. It examines the influences of precipitation, soil texture, pasture age and grass species on soil C balance. Rates of decomposition of residual forest-derived C can be generally similar across a range of soil types in Rondonia, and carbon derived from newly-established pasture vegetation plays an important role in the development of pasture surface soil C stocks. This suggests that factors that increase grass productivity will have the greatest effect on soil C accumulation. There are relatively few studies of soil C balance after deforestation for pasture in the extensive area over which pasture agriculture dominates cleared forest lands. The maintenance of soil C depends both on the stability of organic matter derived from the former forest vegetation and the rate of organic matter input from planted pasture grasses.
