The thicknesses of organic (O) and organomineral (A) horizons are essential parameters for estimating the soil organic carbon stock. They are usually measured at sampling points distributed randomly or regularly over a site, but due to high spatial variability of the soil horizons' thicknesses, the sampling should be dense enough to estimate the carbon stock precisely. Dense soil sampling is cost, time, and labour demanding. Therefore, some studies suggest that geophysical methods such as ground-penetrating radar (GPR) can assist with a more precise estimation of the organic and organomineral horizons thicknesses without digging soil pits. This study evaluates the accuracy of the organic and the organomineral horizons thicknesses repeatedly measured under different soil moisture conditions on two contrasting soil types: Dystric Cambisol and Arenic Podzosol, using GPR with 800 MHz antenna. The results proved this method to be promising; however, we could not distinguish the boundary between organic and organomineral horizons but only the O + A horizon/subsoil boundary. The thickness of O + A horizons was estimated with an error between 25 and 35% in the Dystric Cambisol site and 18 – 24% in the Arenic Podzol site. The results were more accurate under moister conditions for both soil types, but under drier conditions, deeper parts of irregular horizon boundaries were better distinguishable.

有机 (O) 和有机矿物 (A) 层的厚度是估算土壤有机碳储量的基本参数。它们通常在随机或规则分布的采样点上测量，但由于土壤层厚度的高度空间变异性，采样应该足够密集以精确估计碳储量。密集的土壤采样需要成本、时间和劳动力。因此，一些研究表明，诸如探地雷达 (GPR) 等地球物理方法可以帮助更精确地估计有机和有机矿物层厚度，而无需挖掘土壤坑。本研究评估了在不同土壤水分条件下对两种对比土壤类型重复测量的有机和有机矿物层厚度的准确性：Dystric Cambisol 和 Arenic Podzosol，使用带有 800 MHz 天线的 GPR。结果证明这种方法是有前途的；然而，我们无法区分有机层和有机矿物层之间的边界，而只能区分 O + A 层/底土边界。O + A 层的厚度估计在 Dystric Cambisol 站点的误差在 25% 到 35% 之间，在 Arenic Podzol 站点的误差在 18% 到 24% 之间。在两种土壤类型的潮湿条件下，结果更准确，但在干燥条件下，不规则地平线边界的较深部分更容易区分。O + A 层的厚度估计在 Dystric Cambisol 站点的误差在 25% 到 35% 之间，在 Arenic Podzol 站点的误差在 18% 到 24% 之间。在两种土壤类型的潮湿条件下，结果更准确，但在干燥条件下，不规则地平线边界的较深部分更容易区分。O + A 层的厚度估计在 Dystric Cambisol 站点的误差在 25% 到 35% 之间，在 Arenic Podzol 站点的误差在 18% 到 24% 之间。在两种土壤类型的潮湿条件下，结果更准确，但在干燥条件下，不规则地平线边界的较深部分更容易区分。