The area-wide estimation of aboveground biomass (AGB) and its changes as a proxy for the sequestration and emission of carbon are currently associated with high uncertainties. Here we combined interferometric synthetic aperture radar (InSAR) height models derived from TanDEM-X with repeated ground-based inventories from the years 2012 and 2019 to estimate InSAR height and AGB changes in a structurally diverse and dynamic landscape in Sumatra, Indonesia. The results suggested that the InSAR height models were highly accurate and the relationship between InSAR height and AGB change resulted in a coefficient of determination $R^2$ of 0.65 and a cross-validated root mean square error (RMSE) of 2.38 Mg ha⁻¹ year⁻¹, equivalent to 13.32% of the actual AGB difference range. The estimated AGB changes with TanDEM-X were further related to the initial canopy height and fire activities in the study area. Initial canopy heights and the occurrences of fires had a significant effect on the AGB change. In general, low canopy heights tend to be associated with increasing AGB over time, whereas high canopy heights tend to be associated with stable or decreasing AGB. As expected, fires had a negative impact on the AGB changes being more pronounced in forest areas compared to oil palm concessions. The results of this study are relevant for the utilization of spaceborne InSAR height models and its potential to estimate canopy height and AGB change on large spatial scales. It was demonstrated that these changes can be related to their sources and ecosystem processes. This AGB change estimation technique can be used to model the impacts of fires on AGB change and carbon emissions, which are important for sustainable forest management.

地上生物量 (AGB) 的区域范围估计及其作为碳固存和排放代理的变化目前与高度不确定性相关。在这里，我们将源自 TanDEM-X 的干涉合成孔径雷达 (InSAR) 高度模型与 2012 年和 2019 年的重复地面清单相结合，以估计印度尼西亚苏门答腊结构多样化和动态景观中的 InSAR 高度和 AGB 变化。结果表明 InSAR 高度模型具有较高的准确度，InSAR 高度与 AGB 变化之间的关系导致了一个决定系数${\mathrm{电阻}}^2$0.65 和交叉验证的均方根误差 (RMSE) 为 2.38 Mg ha ^-1年^-1，相当于实际 AGB 差异范围的 13.32%。TanDEM-X 的估计 AGB 变化进一步与研究区域的初始冠层高度和火灾活动有关。初始冠层高度和火灾的发生对 AGB 变化有显着影响。一般来说，低冠层高度往往与 AGB 随时间增加有关，而高冠层高度往往与稳定或下降的 AGB 相关。正如预期的那样，与油棕特许经营区相比，火灾对森林地区的 AGB 变化产生了更明显的负面影响。这项研究的结果与星载 InSAR 高度模型的利用及其在大空间尺度上估计冠层高度和 AGB 变化的潜力有关。结果表明，这些变化可能与其来源和生态系统过程有关。