Carbon fixation and shade percentage in coffee (Coffea arabica L.) production systems in Líbano, Tolima, Colombia

摘要

Coffee plantation with trees represents an important system for carbon sequestration and a strategy to mitigate global climate change. In this research it was studied the fixation rate and storage of carbon in the following coffee production systems in L?-bano, Tolima, Colombia: 1) monoculture plantation; 2) agroforestry systems (AFS) with plantain (Musa AAB); 3) AFS with salmwood (Cordia alliodora); and 4) AFS with rubber trees (Hevea brasiliensis). Sample plots were established to measure stem diameter and height on coffee plants, along with stem diameter of trees. Total aboveground biomass of plants was estimated using available biomass models for those species. It was found that the average rate of carbon fixation in AFS with salmwood (4.37 Mg?·ha-1?·yr-1) was higher (P≤0.05) than the rest of the coffee production systems, and the trees showed to be the system component that accounted for most carbon storage (3.57 and 1.20 Mg?·ha-1?·yr-1 for salmwood and rubber trees, respectively). By the time of the study, the AFS with salmwood had achieved a carbon storage of  36.7 Mg ha-1 in 8.4 years, the AFS with rubber tree 22.9 Mg ha-1 in 14.6 years, the AFS with banana 1.3 Mg?·ha-1 in 2.1 years, and the coffee monoculture 2.2 Mg?·ha-1 in 3.5 years. The greatest carbon fixation was found with a shade of 33 %, showing the potential of these production systems to be included in carbon sequestration projects.