Macrophytes play important functional roles in river ecosystems, providing habitat and food, as well as influencing flow, water chemistry, and sediment dynamics. They also represent an important component of river biodiversity. Artificial river barriers have the potential to disrupt macrophyte dispersal, and compromise their distribution and persistence, but little information is available compared to barrier impacts on fish and macroinvertebrates. Here, we review the mechanisms supporting dispersal of river macrophytes in rivers and evaluate the nature of barrier impacts on macrophytes. Hydrochory (dispersal of propagules by water) is the principal mechanism of downstream dispersal, while zoochory (dispersal of propagules by animals) is likely to be the most important vector of upstream dispersal and inter‐catchment transport. Most studies have focused on the impact of large structures such as dams, and the findings indicate the impact is highly context dependent. Slow‐flowing habitats upstream of dams can act as traps to drifting propagules and thereby interrupt hydrochory. However, the consequences of interrupted hydrochory for downstream populations are unclear. River regulation can result in lower macrophyte diversity, although the lentic habitats associated with reservoirs can also favour an increase in the abundance and richness of macrophyte communities. Instream barriers are unlikely to affect zoochory by birds directly, but barriers are well known to restrict fish movements, so there is considerable potential for barriers to disrupt zoochory by fish, although no empirical study has specifically examined this possibility. There is a paucity of studies examining the impacts of low‐head barriers on macrophyte dispersal. Given the influence of macrophytes on river processes, we call for further research into barrier impacts on macrophyte population dynamics in order to gain a better understanding of the consequences of river fragmentation for fluvial communities and ecosystem functioning.

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人工屏障对河流中大型维管植物连通性和扩散的影响：批判性评论

大型植物在河流生态系统中发挥着重要的功能作用，提供栖息地和食物，并影响水流、水化学和沉积物动力学。它们也是河流生物多样性的重要组成部分。人工河流屏障有可能破坏大型植物的传播，并损害它们的分布和持久性，但与屏障对鱼类和大型无脊椎动物的影响相比，可用的信息很少。在这里，我们回顾了支持河流大型植物在河流中扩散的机制，并评估了屏障对大型植物影响的性质。Hydrochory（通过水传播繁殖体）是下游传播的主要机制，而zoochory（通过动物传播繁殖体）可能是上游传播和流域间运输的最重要载体。大多数研究都集中在大坝等大型结构的影响上，研究结果表明这种影响高度依赖于环境。大坝上游的缓慢流动的栖息地可以充当漂流繁殖体的陷阱，从而中断水文。然而，中断水源对下游种群的影响尚不清楚。河流调节会导致大型植物多样性降低，尽管与水库相关的静息栖息地也有利于大型植物群落的丰度和丰富度的增加。河内障碍不太可能直接影响鸟类对动物的影响，但众所周知，障碍会限制鱼类的活动，因此障碍有相当大的潜力可以通过鱼类破坏动物，尽管没有实证研究专门研究这种可能性。很少有研究检查低水头障碍对大型植物扩散的影响。鉴于大型植物对河流过程的影响，我们呼吁进一步研究屏障对大型植物种群动态的影响，以便更好地了解河流破碎化对河流群落和生态系统功能的影响。