老挝革新开放（1986）提出到2020年要逐步稳定刀耕火种农业。地缘经济、林业政策及人口压力已造成刀耕火种农业利用强度增大、休耕周期缩短，对山民生计、土壤碳固持、生物多样性等造成影响。兼具农林复杂动态属性与过去遥感时序产品获取受限，客观制约了刀耕火种农业及其休耕期演变的动态监测研究。项目在利用MODIS指数产品率定刀耕火种农业不同阶段植被–水分指数阈值区间的基础上，基于Landsat植被–水分指数组合改进、发展历年新开辟刀耕火种物候监测算法，提取老挝北部1986年以来逐年新开辟刀耕火种信息，运用景观指数研究刀耕火种农业景观格局变化，基于空间分析研究其利用强度时空特征；在像元尺度上提出刀耕火种农业休耕年限与休耕周期动态变化评价方法，通过时空转换，揭示老挝北部近40年来刀耕火种农业休耕期变化过程与特征；研究刀耕火种农业利用强度、休耕期变化与人口增长、建设用地扩张的相互关系，评价其未来发展趋势。

Since the adoption and implementation of the New Economic Mechanism in the 4th Party Congress in 1986, Government of Lao has aimed to curb and eventually stabilize swidden agriculture in 2020. Geo-economics, forestry policies and human population pressure have greatly enhanced the land use intensity of swiddening (or slashing and burning) and shortened the related fallow periods of swiddening agriculture, which have exerted extensive effects on the local livelihoods of upland farmers, soil carbon sequestration and biological diversity. The facts that swidden agriculture showing agroforestry attributes of complexity and diversity, and limited availability of time-series remote sensing data products in the past (say, Landsat before 2008), have greatly restricted the continuous and extensive monitoring analyses of the spatial and temporal dynamics of swidden agriculture and its fallow length. In this study, threshold values or intervals of vegetation-moisture spectral indices for varied temporal stages (from pre-slash, post-slash or sun/air drying, vegetation burning, post-burn, crops cultivation to fallowing) of swidden agriculture will be carefully and repeated determined using Moderate Resolution Imaging Spectroradiometer (MODIS) time-series fires and vegetation indices data products since 2000. Consequently, novel, modified, and improved phenology-based monitoring algorithms for the detection and mapping of the newly burned plot (NBP) of swidden agriculture each year based on the combinations of Landsat-derived vegetation-moisture indices (such as NDVI, EVI, SAVI, LSWI, and NBR) will be applied to consistently generate the thematic NBPs information of swidden agriculture in northern Laos year by year since 1986. By means of landscape indices and GIS-based spatial analyses, the dynamics of landscape pattern and land use intensity of swidden agriculture will be compared and investigated accordingly. New approaches for assessing the changes of fallow ages and fallow periods of swidden agriculture will also be innovatively devised at the pixel level. In combination with the Space-Time Conversion method, the change processes and characteristics of fallow periods of swidden agriculture in northern Laos in the past four decades (1986-2023) will be comprehensively studies at its first time. Finally, with national population census data (1985, 1995, 2005, 2015 and 2020) and Sentinel-2 A/B derived expansion information of built-up land since 2016, their mutual relationships with the changes in land use intensity and fallow length will be clearly and respectively revealed for the future projection of the development of swidden agriculture.