Only in the years 2007–2016 about 8000 large dams were constructed all over the world, adding to >50,000 previously built dams. These structures disturb abiotic and biotic components of rivers, but to date the knowledge of their impacts has been mainly derived from observations of downstream river reaches. Upstream from dams, however, backwater fluctuations induce sediment deposition, cause more frequent and higher valley-floor inundation, increase groundwater level, and change channel morphology and riparian vegetation. Little is known on the effects of these disturbances on the river biogeomorphological processes.

In this review I synthesized knowledge on backwater effects on rivers into a model of backwater-induced abiotic–biotic interactions in the fluvial system. This model is next used to propose new hypotheses and research tasks concerning the biogeomorphology of gravel-bed rivers in the temperate climatic zone. Implications for flow–sediment–morphology–vegetation interactions and feedbacks are conceptualized in a river cross-section based on recent biogeomorphological insights and methodological approaches allowing to explore them in future studies. The model highlights that backwater-induced changes in abiotic and biotic components of river system trigger further feedbacks between them that additionally influence these components even without a direct backwater influence. Backwater-induced changes in hydrodynamics and sediment transport favour seed germination and growth of plants and decrease their mortality during floods, but also eliminate plants intolerant to prolonged inundation and intensive fine sediment deposition. These impacts may change the biogeomorphical structure of river system by modifying trajectories of biogeomorphic succession cycles and related zones of vegetation–hydromorphology interactions in the river corridor. Specifically, backwater effects may promote the development of more stable channel morphology and a less diverse mosaic of riparian vegetation and animals habitats, contrasting with those occurring in free-flowing rivers of the temperate zone.

仅在2007-2016年，全世界就建造了8000座大水坝，而以前建造的水坝则增加了50,000多个。这些结构扰乱了河流的非生物和生物成分，但迄今为止，其影响的知识主要来自下游河段的观测。但是，在大坝上游，回水的波动引起沉积物的沉积，引起更频繁和更高的谷底洪水泛滥，增加地下水位，并改变河道形态和河岸植被。这些干扰对河流生物地貌过程的影响知之甚少。

在这篇综述中，我将关于回水对河流的影响的知识综合到了由回水在河流系统中引起的非生物－生物相互作用的模型中。接下来，该模型将用于提出有关温带气候区砾石床河流生物地貌的新假设和研究任务。基于最新的生物地貌学见解和方法论方法，可以在河流横断面上概念化河流-沉积物-形态-植被相互作用和反馈的含义，从而可以在未来的研究中对其进行探索。该模型强调，回水引起的河流系统非生物和生物成分变化会触发它们之间的进一步反馈，即使没有直接回水影响，它们也会进一步影响这些成分。回水引起的水动力和泥沙输送变化有利于植物种子的发芽和生长，并在洪水期间降低其死亡率，但同时也消除了不耐长时间浸水和密集的细沙沉积的植物。这些影响可能会通过修改生物地貌演替循环的轨迹以及河流走廊中植被与水文形态相互作用的相关区域来改变河流系统的生物地貌结构。特别地，与温带地区自由流动的河流中发生的水形成对比，回水效应可能促进更稳定的河道形态的发展以及河岸植被和动物栖息地的较少多样性的镶嵌。而且还能消除不耐长时间浸水和密集的细沙沉积的植物。这些影响可能会通过修改生物地貌演替循环的轨迹以及河流走廊中植被与水文形态相互作用的相关区域来改变河流系统的生物地貌结构。特别地，与温带地区自由流动的河流中发生的水形成对比，回水效应可能促进更稳定的河道形态的发展以及河岸植被和动物栖息地的较少多样性的镶嵌。而且还能消除不耐长时间浸水和密集的细沙沉积的植物。这些影响可能会通过修改生物地貌演替循环的轨迹以及河流走廊中植被与水文形态相互作用的相关区域来改变河流系统的生物地貌结构。特别地，与温带地区自由流动的河流中发生的水形成对比，回水效应可能促进更稳定的河道形态的发展以及河岸植被和动物栖息地的较少多样性的镶嵌。