Carbon flux and patterns of land-use/land-cover change in the Selva Lacandona, Mexico

Based on land-use/land-cover (LU/LC) maps for the 1970s and satellite image ry for the 1990s we estimate LU/LC change and associated C fluxes in 3 subr egions of the Selva Lacandona, Chiapas, Mexico. The total area of closed fo rest was reduced by 31%, whereas secondary forests expanded more than ninef old, secondary shrubs by almost sixfold, and cultivated land and pasture ar eas expanded 21% and 92%, respectively. However, the LU/ LC change was not uniformly distributed over the entire study area. Total mean C densities ra nged from 452 Mg C ha(-1) for closed mature forests to a low of 120 Mg C ha (-1) for pasture. The heavily converted areas lost an estimated 24% of thei r total 1976 C poets, whereas the low impacted region lost only 3%.