Climate change, river regulation and water extraction create the conditions where destratification-driven hypoxia will become more common in rivers. Preventing this and the fish deaths that can result requires options that prevent stratification and create oxygen refuges for fish. Here we discuss aeration and mixing approaches that may help prevent fish deaths when flow-related measures are not available. The options were evaluated based on efficacy, environmental risk and readiness to be deployed cost-effectively. The options either promote mixing, aeration or both. Bubble diffusers and paddle wheels used commonly in aquaculture are unlikely to aerate already hypoxic pools. However, if deployed before stratification occurs, they may promote mixing and maintain aeration. In comparison, pumps with Venturi tubes or ultrafine oxygen bubble condensers both mix and aerate, making them suitable for use once hypoxic events are underway. Water jets are low cost and could be deployed quickly. Dosing reaches with calcium peroxide may be useful for emergency aeration, but requires further safety and efficacy testing. Flow management that maintains fish refuges and storage reserves during drought is the best way to guard against fish deaths, but if storage releases are not available, there are options for creating and maintaining oxygen refuges to minimise ecosystem damage.

气候变化、河流调节和取水创造了条件，使河流中的去层化驱动的缺氧变得更加普遍。防止这种情况和可能导致的鱼类死亡需要防止分层并为鱼类创造氧气避难所的选择。在这里，我们讨论了在没有流量相关措施时可能有助于防止鱼类死亡的曝气和混合方法。这些选项是根据功效、环境风险和成本效益部署的准备情况进行评估的。这些选项可以促进混合、曝气或两者兼而有之。水产养殖中常用的气泡扩散器和桨轮不太可能对已经缺氧的水池充气。但是，如果在分层发生之前部署，它们可能会促进混合并保持曝气。相比下，带有文丘里管或超细氧气泡冷凝器的泵既可以混合又可以充气，因此一旦发生缺氧事件，它们就适合使用。水射流成本低，可以快速部署。使用过氧化钙的剂量范围可能对紧急曝气有用，但需要进一步的安全性和有效性测试。在干旱期间维持鱼类避难所和存储储备的流量管理是防止鱼类死亡的最佳方法，但如果无法获得存储释放，则可以选择创建和维护氧气避难所以最大程度地减少对生态系统的破坏。