Flow regulation impacts on riparian vegetation composition, often increasing the prevalence of exotic and terrestrial plant species. Environmental flows may benefit native riparian vegetation via the promotion of plant recruitment from riparian soil seedbanks, but this is dependent on an intact native seedbank. Thus, we assessed the composition of the soil seedbank of different riverine geomorphic features to determine its potential response to environmental flows. Soil seedbank samples were taken from channel bars, benches and floodplains at six sites along the Campaspe River, Australia, a heavily regulated river that receives environmental flows. These geomorphic features represent a gradient in elevation and thus flooding frequency from frequently flooded (bars) to infrequently flooded (floodplain). Seedbank samples were ‘grown out’ in a glasshouse, and seedlings identified and classified according to taxa, flood tolerance and origin (native or exotic). We identified 6515 seedlings across all geomorphic features and sites, with monocots most abundant. Soil seedbank composition varied between geomorphic features. Overall, seedling abundances were greater for in-channel features (bars and benches) than floodplains, but taxa richness did not vary likewise. Soil seedbanks of in-channel features were dominated by flood tolerant and native taxa, while flood intolerant and exotic taxa were generally associated with floodplains. The dominance of native flood tolerant taxa in the soil seedbanks of in-channel geomorphic features suggest these seedbanks can play an important role in the resilience of native riparian plant communities. Moreover, environmental flows are likely to play a positive role in maintaining native riparian plant communities given such conditions.

流量调节影响河岸植被组成，通常会增加外来和陆生植物物种的流行。环境流可能通过促进河岸土壤种子库的植物补充使当地河岸植被受益，但这取决于完整的原生种子库。因此，我们评估了不同河流地貌特征的土壤种子库的组成，以确定其对环境流量的潜在响应。土壤种子库样本取自澳大利亚坎帕斯佩河沿岸六个地点的河道坝、长凳和洪泛区，这条河受到环境流量的严格监管。这些地貌特征代表了海拔梯度，因此洪水频率从经常被淹（条形）到不经常被淹（泛滥平原）。种子库样本在温室中“生长”，根据分类群、耐洪性和来源（本地或外来）对幼苗进行识别和分类。我们在所有地貌特征和地点确定了 6515 株幼苗，其中单子叶植物最为丰富。土壤种子库组成因地貌特征而异。总体而言，河道内特征（酒吧和长凳）的幼苗丰度高于泛滥平原，但类群丰富度没有同样变化。河道特征的土壤种子库以耐洪和本地类群为主，而不耐洪和外来类群通常与漫滩有关。河道内地貌特征的土壤种子库中原生耐洪类群的优势表明这些种子库可以在原生河岸植物群落的恢复力中发挥重要作用。而且，