Satellite data reveals a recent increase in shifting cultivation and associated carbon emissions in Laos

Abstract

Although shifting cultivation is the major land use type in Laos, the spatial-temporal patterns and the associated carbon emissions of shifting cultivation in Laos are largely unknown. This study provides a nationwide analysis of the spatial-temporal patterns of shifting cultivation and estimations of the associated carbon emissions in Laos over the last three decades. This study found that shifting cultivation has been expanding and intensifying in Laos, especially in the last 5 years. The newly cultivated land from 2016 to 2020 accounted for 4.5% (±1.2%) of the total land area of Laos. Furthermore, the length of fallow periods has been continuously declining, indicating that shifting cultivation is becoming increasingly intensive. Combining biomass derived from Global Ecosystem Dynamics Investigation and shifting cultivation maps and area estimates, we found that the net carbon emissions from shifting cultivation declined in 2001–2015 but increased in 2016–2020. The largest carbon source is conversion from intact forests to shifting cultivation, which contributed to 89% of the total emissions from 2001 to 2020. In addition, there were increased emissions from intensified use of fallow lands. This research provides useful information for policymakers in Laos to understand the changes in shifting cultivation and improve land use management. This study not only supports Reducing Emissions from Deforestation and Forest Degradation reporting for Laos but also provides a methodology for tracking carbon emissions and removals of shifting cultivation.