Replication Data for: Comparison of aboveground vegetation and soil seed bank composition at sites of different grazing intensity around a savanna-woodland watering point in West Africa

Grazing removes a plant’s aboveground vegetative and reproductive tissues and can modify the soil seed bank, potentially impacting the restoration of preferred species. Knowledge about aboveground vegetation and species composition of soil seed bank and the processes that contribute to vegetation recovery on and surrounding watering points subjected to grazing is lacking. Successful restoration strategies hinge on addressing these knowledge gaps. We assessed the effects of livestock grazing on aboveground vegetation and soil seed bank characteristics along a river bank and surrounding areas subject to different grazing intensities and draw implications for restoration. Plots (50 × 50 m) were established along five transects representing differing levels of grazing intensity. Soil samples were taken from three layers within each plot to determine soil properties and species composition of soil seed bank using the seedling emergence method. Heavy grazing resulted in the disappearance of perennial grasses, a reduction in species diversity and a decrease in soil nutrients with increased soil depth. Overall, the similarity between the extant aboveground vegetation and flora within the soil seed bank was low. The soil seed bank was dominated by herbaceous species and two woody species, suggesting that many woody species are not accumulating in the soil. With increasing soil depth, the seed density and richness declined. Canonical correspondence analyses (CCAs) showed that emerged seedlings from the soil seed bank were significantly influenced by soil carbon, organic matter, total nitrogen, total potassium and soil cation exchange capacity. This finding suggests that current grazing practices have a negative impact on the vegetation surrounding watering points; hence there is a need for improved grazing management strategies and vegetation restoration in these areas. The soil seed bank alone cannot restore degraded river banks; active transfer of propagules from adjacent undisturbed forest areas is essential.放牧可去除植物的地上营养组织与繁殖器官，同时改变土壤种子库（soil seed bank），进而可能对目标恢复物种的植被重建产生不利影响。目前学界对放牧影响下水源点及其周边区域的地上植被、土壤种子库物种组成，以及驱动该区域植被恢复的相关过程仍缺乏系统认知，而行之有效的植被恢复策略，有赖于填补上述认知空白。 本研究针对不同放牧强度下的河岸带及其周边区域，评估了家畜放牧对地上植被与土壤种子库特征的影响，并为区域植被恢复工作提供理论参考。研究沿代表不同放牧强度梯度的5条样带，设置了50×50 m的样地；从每个样地的三层土壤中采集土样，采用幼苗萌发法（seedling emergence method）测定土壤理化性质与土壤种子库的物种组成。 高强度放牧会导致多年生草本植物消失、物种多样性降低，且随土壤深度增加，土壤养分含量逐渐下降。总体而言，现存地上植被与土壤种子库中的植物区系之间的相似性较低。土壤种子库以草本植物与2种木本植物为优势类群，这表明多数木本植物并未在土壤中形成种子库积累。随土壤深度增加，种子密度与物种丰富度均呈下降趋势。 典范对应分析（Canonical correspondence analyses, CCAs）结果显示，土壤种子库萌发的幼苗群落显著受到土壤碳、有机质、全氮、全钾及土壤阳离子交换量的影响。该结果表明，现行放牧模式对水源点周边的植被具有不利影响，因此上述区域亟需优化放牧管理策略并开展植被恢复工作。仅依靠土壤种子库无法实现退化河岸带的恢复，从周边未受干扰的林区主动移植繁殖体是必不可少的手段。