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随着现代遥感观测技术的不断发展，目前已经有多个版本的公开高程数据集。然而，在林区，由于植被对电磁波的遮挡或吸收作用，遥感手段探测得到的高程不能反映真实的地表信息，存在系统偏差的影响。为了分析多源DEM产品在林区高程偏差的特性，本文选取了美国马里兰州和索诺马县为研究区域，对比不同地形、不同林区类型条件下雷达DEM产品SRTM1、TanDEM-X 90和光学DEM产品AW3D 30与裸地参考高程3DEP的差值，得到三类高程产品的林区穿透率，并结合林区类型、植被冠层高度、冠层覆盖度和坡度等辅助数据进行差异分析。结果表明，在所有研究区域中，C波段雷达数据SRTM1的整体林区穿透率最大，尤其是在马里兰州常绿针叶林，其整体穿透率可达0.771。而基于X波段雷达观测的TanDEM-X 90和光学数据AW3D 30的林区穿透率相当。三类高程产品在针叶林中的林区穿透率大于在阔叶林中的林区穿透率，且林区穿透率均随着冠层覆盖度的增加而减弱，其中TanDEM-X 90和AW3D 30的林区穿透率减弱幅度较大。除探测波长影响外，主要原因是TanDEM-X 90和AW3D 30都是由高分辨率数据采样得到，重采样前的高分辨率原始数据更容易检测到树木之间的开阔区域。因此，在林区中对SRTM1、TanDEM-X 90和AW3D 30三类高程产品进行应用时，应综合考虑传感器波段的穿透性、林区类型、冠层覆盖度以及坡度的影响，根据每个产品的林区穿透率去除植被冠层高度，以获取更加精确的地表信息。
1)Objective With the continuous development of modern remote sensing observation technology, there have been several versions of open elevation data sets. However, in forest areas, due to the shielding or absorption of electromagnetic wave by vegetation, the elevation detected by remote sensing method cannot reflect the real surface information, and there is the influence of systematic deviation. Therefore, the research objective of this paper is to analyze the characteristics of multi-source DEM products in forest region elevation deviation. 2)Method This paper selects Maryland and Sonoma County in the United States as the study area. By comparing the difference between radar DEM product SRTM1, TanDEM-X 90 and optical DEM product AW3D 30 and bare ground reference elevation 3DEP under different terrain and different forest conditions, Obtain the forest penetration rate of the three types of elevation products, and analyze the difference with auxiliary data such as the sensor measurement band, forest type, vegetation canopy height, canopy coverage and slope. 3)Result The results show that the C-band radar data SRTM1 has the highest penetration rate in the overall forest area of all the study areas, especially in the evergreen coniferous forest in Maryland, where the overall penetration rate can reach 0.771, which is also consistent with the SRTM1 data. The forest penetration rate of TanDEM-X 90 based on X-band radar observation and optical data AW3D 30 is equivalent. The penetration rate of the three types of elevation products in the coniferous forest is greater than that in the broad-leaved forest, and the penetration rate of the forest area decreases with the increase of canopy coverage. Among them, TanDEM-X 90 and AW3D 30 The penetration rate of the forest area weakened greatly. In addition to the influence of detection wavelength, the main reason is that TanDEM-X 90 and AW3D 30 are both sampled from high-resolution data. The high-resolution raw data before resampling makes it easier to detect the open area between trees. In addition, the complex terrain environment will reduce the forest penetration rate of SRTM1 to a certain extent. 4)Conclusion Therefore, when applying the three types of elevation products SRTM1, TanDEM-X 90 and AW3D 30 in forest areas, the penetrability of the sensor waveband, forest type, canopy coverage, and slope should be considered comprehensively. The forest penetration rate of the product removes the vegetation canopy height to obtain more accurate surface information. This research is helpful to improve the accuracy of tree height removal for elevation products in the later stage, and at the same time, it provides a scientific reference basis for users when selecting the three types of elevation products.