Tropical forests store 20-40% of terrestrial carbon (C) and contain 90% of all tree species. Land-use change causes species loss and greenhouse gas emissions. However, human-modified tropical landscapes can also mitigate climate change and conserve biodiversity. We are interested in the long-term monitoring of tree diversity and C-sequestration in different land-use types because we have found synergies between tree diversity and C-storage in coffee farms, pastures, and forests in Costa Rica.