Subsidient: Loes Verkuil / Utrecht University
The intensification trends in the Colombian coffee sector towards monoculture systems are putting pressure on the resilience of ecosystems in terms of soil conditions, biodiversity and temperature regulation, resulting in land degradation. As the world is confronted with an environmental crisis, ecosystem restoration initiatives are vital for recovering and sustaining ecosystem service performances. Coffee agroforestry systems are known to benefit ecosystem services, but the temporal effects of the implementation on land restoration are still not fully understood. This study presents a chronosequence analysis on the potential of agroforestry systems to enhance carbon stocks and to mitigate soil erosion, without compromising on coffee productivity. Research was carried out on 55 coffee farms in Risaralda, Colombia, of which 15 farms were monoculture systems and 40 farms transitioned to agroforestry systems. Results show that canopy cover can be established in a short time, which appeared to be an important factor in avoiding soil erosion, together with density of shade trees. Above and belowground carbon stock together was higher in agroforestry systems than in monoculture systems, of which only aboveground carbon stock appeared to increase over time, as did tree diversity. The coffee yield did not change over time and no effects of canopy cover and shade tree density were found. Based on these results, it is recommended to establish agroforestry management practices in monoculture coffee landscapes to recover soil conditions in a short time, avoid further land degradation and to enhance carbon sequestration.