Abstract Woody vegetation provides multiple services to the pastoralists in the Sahel and since the drought of 1972–1984, concerns have been raised about its persistence. Some studies have observed a decline in tree density and specific richness while others have reported a greening at a larger scale. In this study, an extensive field inventory was carried out around two deep wells in the Ferlo (Senegal). The influence of topography and proximity of deep wells on woody vegetation density, diversity and regeneration was studied. An analysis of the size class distribution was carried out to gain insight into the population dynamics of some species. This study highlights the key role of low topographic positions in favouring woody vegetation establishment with a higher species richness and a greater density. The remoteness of deep wells seems to have no effect on these variables. The instability of several tree species populations was evident from the size class analysis. As large trees play an important role in hosting regeneration, the persistence of the current woody vegetation is threatened. Given the positive impact of depressions on woody vegetation, further research should focus on these topographic features and their role as central pieces in a potential management plan.

中文翻译：

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较低的地形位置增强了 Ferlo（塞内加尔萨赫勒）的木本植被稳定性

摘要 木本植被为萨赫勒地区的牧民提供多种服务，自 1972 年至 1984 年的干旱以来，人们对其持续存在表示担忧。一些研究观察到树木密度和特定丰富度的下降，而其他研究则报告了更大规模的绿化。在这项研究中，在 Ferlo（塞内加尔）的两个深井周围进行了广泛的现场清查。研究了地形和深井距离对木本植被密度、多样性和更新的影响。对大小等级分布进行了分析，以深入了解某些物种的种群动态。这项研究强调了低地形位置在有利于具有更高物种丰富度和更大密度的木本植被建立方面的关键作用。深井的偏远似乎对这些变量没有影响。从大小等级分析可以明显看出几种树种种群的不稳定性。由于大树在承载再生方面发挥着重要作用，当前木本植被的持久性受到威胁。鉴于洼地对木本植被的积极影响，进一步的研究应关注这些地形特征及其作为潜在管理计划中核心部分的作用。