Accurate, cost-effective monitoring of plantation aboveground biomass (AGB) is crucial for supporting local livelihoods and carbon sequestration initiatives like the China Certified Emission Reduction (CCER) program. High-resolution canopy height maps (CHMs) are essential for this, but standard lidar-based methods are expensive. While deep learning with RGB imagery offers an alternative, accurately extracting canopy height features remains challenging. To address this, we developed a novel model for high-resolution CHM generation using a Large Vision Foundation Model (LVFM). Our model integrates a feature extractor, a self-supervised feature enhancement module to preserve spatial details, and a height estimator. Tested in Beijing's Fangshan District using 1-meter Google Earth imagery, our model outperformed existing methods, including conventional CNNs. It achieved a mean absolute error of 0.09 m, a root mean square error of 0.24 m, and a correlation of 0.78 against lidar-based CHMs. The resulting CHMs enabled over 90% success in individual tree detection, high accuracy in AGB estimation, and effective tracking of plantation growth, demonstrating strong generalization to non-training areas. This approach presents a promising, scalable tool for evaluating carbon sequestration in both plantations and natural forests.
翻译:准确、经济高效地监测人工林地上生物量(AGB)对于支持当地生计以及中国核证自愿减排量(CCER)计划等碳汇倡议至关重要。高分辨率冠层高度图(CHM)是实现此目标的关键,但基于激光雷达的标准方法成本高昂。虽然利用RGB影像进行深度学习提供了一种替代方案,但准确提取冠层高度特征仍然具有挑战性。为此,我们开发了一种利用大规模视觉基础模型(LVFM)生成高分辨率CHM的新型模型。该模型集成了特征提取器、用于保持空间细节的自监督特征增强模块以及高度估计器。使用1米分辨率的谷歌地球影像在北京房山区进行测试,我们的模型性能优于包括传统CNN在内的现有方法。与基于激光雷达的CHM相比,其平均绝对误差为0.09米,均方根误差为0.24米,相关性为0.78。生成的CHM实现了超过90%的单木检测成功率、高精度的AGB估算以及有效的林分生长跟踪,显示出对非训练区域的强大泛化能力。该方法为评估人工林和天然林的碳汇潜力提供了一种前景广阔、可扩展的工具。