Under limited precipitation, coarse-textured soils may strongly limit tree regeneration success and stand productivity, yet their effective impact depends on layer thickness and the nature of the underlying soil material. Within that context, we have evaluated the performance of two ground-penetrating radar (GPR) techniques to assess the short-scale variability in physical soil properties, using the Maâmora forest and cork oak as a case study. A frequency-domain GPR was developed to map the soil surface water content of a 1 ha, 18-year old cork oak stand. In addition, a time-domain GPR was used to detect soil textural transitions in depth between the sand and clay textures of the same cork oak stand. Intensive GPR measurements were made along transects, together with detailed local stand and soil characterization. The volumetric water contents (ϴ_v) varied between 0.01 m³/m³ and 0.1 m³/m³, which represent available water storage of coarse sands to sandy loams [0.04 m³/m³ - 0.12 m³/m³]. The estimated transition depths detected by the second GPR varied between 1.8 m and 4.0 m deep. Soil water content was found to be a relevant indicator of successful cork oak regeneration as it was strongly related to the dominant heights of the cork oaks. The most successful areas were characterized by higher surface moisture and these higher values were mostly explained by soil texture. Moreover, the layer thickness also influenced cork oak growth. Hence, both radar systems provided useful predictors for the regeneration success of cork oaks. Using GPR for future tree planting would allow foresters to detect the best areas in terms of hydric and edaphic conditions where trees should be installed in order to ensure a successful establishment.

在有限的降水量下，质地粗糙的土壤可能会严重限制树木的再生成功和林分生产力，但其有效影响取决于层厚和下层土壤物质的性质。在此背景下，我们以Maâmora森林和软木橡树为案例，评估了两种探地雷达（GPR）技术的性能，以评估土壤物理性质的短尺度变化。开发了频域GPR，以绘制18年前1公顷的软木栎林的土壤表层水分图。此外，使用时域GPR来检测同一软木栎木林分的沙子和粘土质地之间的深度土壤质地过渡。沿着样带进行了密集的GPR测量，以及详细的局部林分和土壤特征。体积水含量（ϴ _v）在0.01m³/m³和0.1m³/m³之间变化，表示从粗砂到砂质壤土的可用储水量[0.04m³/m³-0.12m³/m³]。第二个GPR探测到的估计过渡深度在1.8 m和4.0 m之间变化。发现土壤含水量是成功软木橡树再生的重要指标，因为它与软木橡树的优势高度密切相关。最成功的区域以较高的表面湿度为特征，而这些较高的值主要由土壤质地来解释。而且，层厚也影响了软木的生长。因此，两个雷达系统都为软木橡树的再生成功提供了有用的预测指标。