Land use and land cover (LULC) change caused by human activities is a major source of anthropogenic carbon emissions and a driver of climate change. The Mekong Region is highly dynamic, experiencing extensive LULC change in recent decades. This study provides a spatially and temporally continuous estimate of LULC change for the Mekong River Basin for 2001–2019 using time series analysis of MODIS data coupled with a spatiotemporal carbon bookkeeping model to track carbon losses and recovery. The LULC change product has an overall accuracy of 74.4 ± 1.9% (82.1 ± 1.7% after consolidating tree-dominated classes), including an increase of 5.6% after combining with existing MODIS products (referred to as the M-CCDC process). Two of the largest components of LULC change in the region are the establishment of plantations and agricultural expansion, which were estimated to be 33,617 ± 7342 km² and 14,915 ± 4682 km² between 2003 and 2014. We found that 82% of the deforested area was converted to tree plantations. Among all the newly added plantations, 86% replaced natural forests and 12% replaced agricultural land. In addition, existing maps of annual tree canopy cover (TCC) were used to assess forest disturbances that do not result in LULC conversions. The M-CCDC results combined with the forest disturbances derived from TCC maps were coupled to a spatiotemporal carbon bookkeeping model to estimate carbon emissions and uptake. Carbon emissions were 72.9 ± 6.2 Tg C yr⁻¹ during 2001–2017; emissions increase to 102.8 ± 8.6 Tg C yr⁻¹ if including carbon not yet released to the atmosphere in the form of decomposing slash and wood products. Carbon uptake for the same period was −35.5 ± 4.9 Tg C yr⁻¹, with carbon uptake from new plantations offsetting almost half of the emissions from deforestation in this area. Assessment of post-deforestation land use is crucial for quantifying the short- and longer- term carbon consequences of LULC change.

人类活动引起的土地利用和土地覆被（LULC）变化是人为碳排放的主要来源，也是气候变化的驱动力。湄公河地区充满活力，近几十年来LULC发生了广泛变化。这项研究使用MODIS数据的时间序列分析，结合时空碳簿记模型来追踪碳损失和回收，从而提供了2001-2019年湄公河流域LULC变化的时空连续估计。LULC变更产品的整体准确度为74.4±1.9％（合并树型类别后为82.1±1.7％），与现有的MODIS产品（称为M-CCDC工艺）组合后的准确度提高了5.6％。该地区土地利用和土地利用变化的两个最大组成部分是种植园的建立和农业的扩张，在2003年至2014年期间分别为²和14,915±4682 km ^2。我们发现82％的森林砍伐面积已转化为人工林。在所有新增加的人工林中，有86％取代了天然林，而12％取代了农地。此外，现有的年度树冠覆盖图（TCC）用于评估不会导致LULC转换的森林干扰。M-CCDC结果与TCC图得出的森林干扰相结合，并结合了时空碳簿记模型以估算碳排放量和吸收量。2001-2017年期间碳排放量为72.9±6.2 Tg C yr ^-1 ; 排放增加到102.8±8.6 Tg C yr ^-1如果包括尚未以分解斜线和木质产品的形式释放到大气中的碳。同期的碳吸收量为-35.5±4.9 Tg C yr ^-1，新种植园的碳吸收量几乎抵消了该地区森林砍伐所产生的排放量。评估毁林后土地利用对于量化土地利用，土地利用变化的短期和长期碳影响至关重要。