The installation of weirs leads to extensive alterations in species composition of riverbank vegetation, as they distinctly change the natural disturbance regime of rivers. Due to their infrastructural significance, the removal of most weirs and impoundments is unlikely, which is why restoration measures along impounded rivers are strongly limited.

To evaluate the restoration potential of weir-near (maximum 400 m distance upstream and downstream from weir) and weir-distant (minimum 1000 m distance from weir) river stretches, we sampled 72 total relevés (24 weir-distant, 24 weir-near upstream, and 24 weir-near downstream) along the German river Lahn in Hesse and Rhineland Palatinate. Weir-distant stretches do not have lockages directly surrounding any weirs like they do in weir-near areas; consequently, the impoundment effect is further minimized, which leads to reduced regulation intensity. Differences in species composition were evaluated by non-metric, multidimensional scaling and indicator species analysis. Species diversity, functional diversity, and csr-signatures were compared to test for differences between upstream, downstream, and weir-distant sites using a Kruskal-Wallis test by ranks and a Posthoc-Kruskal-Nemenyi-Test. Indicator species were used to analyze the distribution of typical species from the transition zone of riverbanks.

Weir-distant vegetation was distinctly different from weir-near vegetation, revealing more similarities to typical floodplain species and species adapted to flooding and changing water levels, higher species diversity, and a somewhat higher functional diversity. R-strategists were more prevalent along the weir-distant reaches; this also applies to species from flooded meadows and grasslands. As these results indicate a more typical species composition for riverbank habitats, weir-distant river stretches are likely to bear a higher potential for successful restoration measures than weir-near river stretches. Thus, regulation intensity is an important factor when planning riverbank restoration measures. As summer annual species from the Bidentetea alliance were rare, we recommend the ecological value of regulated riverbank stretches be assessed by means of species that naturally occur directly above the summer annual species zone. Within our study, these species originate from flooded meadows and grasslands that occurred irrespective of the weir distance and corresponded to water level fluctuation intensity.

堰的安装导致河岸植被物种组成的广泛变化，因为它们明显改变了河流的自然扰动状态。由于其基础设施的重要性，大多数堰和蓄水库的拆除不太可能，这就是为什么严格限制沿蓄水河的恢复措施的原因。

为了评估近堰（距堰上游和下游最大距离为400 m）和远堰（距堰最小距离为1000 m）河段的恢复潜力，我们采样了72个相关物（24个近堰，24个近堰）黑河和莱茵兰普法尔茨州的德国拉恩河上游和下游24堰附近）。堰距离较远的延伸段没有像在堰区附近那样直接在堰周围环绕的锁定装置；因此，蓄水效果进一步最小化，从而导致调节强度降低。通过非度量，多维标度和指示剂物种分析来评估物种组成的差异。比较了物种多样性，功能多样性和csr签名，以测试上游，下游，使用等级的Kruskal-Wallis检验和Posthoc-Kruskal-Nemenyi检验进行测距和测距。指标物种用于分析河岸过渡带典型物种的分布。

远堰的植被与近堰的植被明显不同，揭示了与典型洪泛区物种和适应洪水和变化水位的物种更多的相似性，更高的物种多样性和更高的功能多样性。R策略家在堰坝远处更为普遍。这也适用于淹没的草地和草原上的物种。由于这些结果表明，河岸生境的物种组成更为典型，因此，与堰流较近的河段相比，堰远的河段可能具有更高的成功恢复措施的潜力。因此，调节强度是规划河岸恢复措施时的重要因素。作为Bidentetea的夏季一年生物种联盟很少，我们建议通过自然直接存在于夏季一年生物种带上方的物种来评估受调节河岸段的生态价值。在我们的研究中，这些物种起源于淹没的草地和草原，其发生与堰距无关，并且与水位涨落强度相对应。