Traditional agroforestry systems in Timor-Leste can store large amounts of carbon in both soil and biomass

Abstract Agroforestry has the potential to make agriculture more resilient while improving carbon sequestration by incorporating trees and/or other woody perennials into agricultural land, thereby diversifying landscapes. Traditional agricultural systems in tropical areas often include trees, but their carbon sequestration potential is not always well described, hindering their inclusion in climate change mitigation strategies. In this study, we quantified carbon storage in both vegetation biomass and soil in five traditional agroforestry systems (AFS) in Timor-Leste, namely cropping systems with fallow (CF), silvopastures (SP), young agroforests (YA), home gardens (HG), and forest gardens (FG). Our results show that these traditional AFS can store large amounts of carbon, with the average total carbon stocks (soil and biomass) being 155 Mg C ha−1. The AFS with the highest total carbon stocks (FG) stored an average of 213 Mg C ha−1. The average stocks in the other AFS were 108 Mg C ha−1 in CF, 158 Mg C ha−1 in SP, 134 Mg C ha−1 in YA, and 171 Mg C ha−1 in HG. Biomass carbon stocks varied substantially between AFS, while soil carbon stocks were less variable between AFS but more site-dependent. We found no relationship between the amount of carbon stored in biomass and soil. Our results highlight the diversity of traditional AFS in Timor-Leste and their carbon sequestration capacity. These results could provide an important baseline for the inclusion of AFS in Timor-Leste’s climate change mitigation strategy, and could serve as a reference for future AFS studies in different agro-climates of Timor-Leste.