Flushing flows are deliberate high-flow releases designed to mimic effects of floods in removing fine sediment from downstream aquatic habitats. A special case of environmental flows, flushing flows are intended to act on geomorphic processes to mitigate ecological effects of dams. We review definitions advanced for these flows, and then propose a new term, morphogenic releases, for high flows designed to interact with the channel to produce biophysical changes in channel characteristics. Similarly, ecomorphogenic releases is proposed for those flows intended specifically to improve aquatic and riparian habitats. We then review objectives of such specific environmental flows and potential conflicts with environmental, socio-economic, and dam-operational issues. We also provide some recommendations based on our literature review and experiences to specify the dimensions of morphogenic flows. Experiments to assess effects of morphogenic flows are increasingly part of the process of defining environmental flows. We highlight the challenges to implement morphogenic flows and some alternative actions when such flows cannot be implemented, recognizing that flow is not the only variable of interest downstream of dams to mitigate effects of dams; that mitigation of channel form, sediment supply, water quality, or other factors may also be important. Returning the channel to a pre-regulation state is often not possible, and it is necessary to address issues pragmatically by identifying the most efficient improvement options and what is financially feasible and socially desirable.

冲洗水是有意释放的高水流，旨在模拟洪水在从下游水生生境中清除细小沉积物的影响。在环境流量的一种特殊情况下，冲洗流量旨在作用于地貌过程，以减轻大坝的生态影响。我们回顾了针对这些流动的高级定义，然后针对旨在与通道相互作用以在通道特性中产生生物物理变化的高流量提出了一个新术语，形态发生释放。同样，生态形态释放建议将这些流量专门用于改善水生和河岸生境。然后，我们审查此类特定环境流量的目标以及与环境，社会经济和大坝运营问题的潜在冲突。我们还根据我们的文献综述和经验提供一些建议，以指定形态发生流的大小。评估形态发生流影响的实验越来越多地成为定义环境流过程的一部分。我们认识到实现形态发生流的挑战以及在无法实现形态发生流时采取的其他措施，因为认识到流量并不是减轻大坝下游影响的唯一利益变量。缓解河道形式，沉积物供应，水质或其他因素也可能很重要。