Monitoring shifting cultivation in Laos with Landsat time series

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

“…After short-term cultivation, the plot is abandoned, which allows the vegetation to recover. Shifting cultivation is the predominant land use and a major cause of forest degradation and deforestation in some tropical countries (Heinimann et al 2017, Curtis et al 2018, Jiang et al 2022, such as Laos (Chen et al 2023), and the Democratic Republic of Congo (Molinario et al 2015). Monitoring shifting cultivation is complicated, because it is highly dynamic, and the area affected by each slash-and-burn event is small.…”

“…In Laos, officially the Lao People's Democratic Republic (Lao PDR), shifting cultivation is an important agricultural system (Roder 2001, Douangsavanh et al 2006, Epprecht et al 2018, Manivong and Cramb 2020 and the major driver of forest dynamics (Curtis et al 2018, Chen et al 2023. It is estimated that shifting cultivation affected 32.9 ± 1.9% of Laos from 1991 to 2020, and the shifting cultivation activities increased in the most recent 5 years (Chen et al 2023). Laos' population has been increasing steadily from 4.314 million in 1990 to 7.319 million in 2020 (World Bank 2023), whereas upland rice yields did not distinctly improve between 1990 and 2020.…”

“…Monitoring shifting cultivation and analyzing its patterns are important to understand the forest cover change in Laos and relevant to achieving Laos' goal of increasing forest cover to 70% (The current forest cover is 62%) (The Government of Lao PDR 2005). Since there were few spatially and temporally explicit maps and estimates of shifting cultivation before Chen et al (2023), carbon emissions from shifting cultivation have not been accurately estimated in the REDD+ reporting of Laos (Department of Forestry, Ministry of Agriculture and Forestry, Lao PDR 2018).…”

“…Spatially and temporally explicit information about shifting cultivation in Laos was unavailable until recently (Chen et al 2023), and a comprehensive national-scale analysis of the spatial and temporal patterns of shifting cultivation has not been conducted to date. A traditional approach for mapping shifting cultivation is to create landscape mosaics based on a land cover map of a single year (Messerli et al 2009, Silva et al 2011, Hett et al 2012, Hurni et al 2013a.…”

“…In previous studies, the temporal resolution of the land cover maps was not high enough to support the analysis of temporal patterns (Heinimann et al 2013). Recently, Chen et al (2023) used satellite data to create shifting cultivation products for Laos with sufficient temporal frequency (annual) and spatial resolution (30 m) to support a nationalscale spatial-temporal analysis. The recently launched GEDI (Global Ecosystem Dynamics Investigation) mission provides new opportunities for estimating biomass at a large scale (Tang et al 2020).…”