1. Climate warming is causing changes in the physics of deep lakes, such as longer summer stratification, increased water column stability, reduced ice cover, and a shallower depth of winter overturns. An ultimate consequence of warming would be a transition to a different mixing regime. Here we investigate the role of physical, chemical, and biological feedback mechanisms that unfold during a shift in mixing regime, and whether these feedbacks could prompt and stabilise the new regime. Although climate, interannual temperature variation, and lake morphometry are the main determinants of a mixing regime, when climate change causes shifts in mixing regime, internal feedback mechanisms may gain in importance and modify lake ecosystem functioning.
2. We review the role of these feedbacks in three mixing regime shifts: from polymictic to seasonally stratified, from dimictic to monomictic, and from holomictic to oligomictic or meromictic.
3. Polymictic lakes of intermediate depth (c. 3–10 m mean depth) could experience seasonal stratification if a stratification event triggers phytoplankton blooms or dissolved organic matter release, reducing transparency and therefore further heating the surface layer. However, this feedback is only likely to have influence in small and clear lakes, it would be easily disturbed by weather conditions, and the resulting stratified state does not remain stable in the long term, as stratification is lost in winter.
4. The ice‐albedo feedback might cause an accelerated shift from ice‐covered (dimictic) to ice‐free (monomictic) winters in sufficiently deep (mean depth 50 m or more) lakes, where temperature memory is carried over from one winter to the next. Nevertheless, there is an ongoing debate into whether this process can persist during natural weather variations and overcome self‐stabilising mechanisms such as thermal insulation by snow. The majority of studies suggest that a gradual transition from dimictic to monomictic is more likely than an abrupt transition.
5. A shift from a holomictic to a meromictic regime can occur if anoxia is triggered by incomplete mixing and an increase in deep‐water density—through the accumulation of solutes—exceeds a density decrease by hypolimnetic warming. A shift to meromixis would strongly alter the biology of a lake and might be difficult to reverse. If solutes accumulate only minimally in the hypolimnion, an oligomictic regime is formed, in which years with complete and incomplete mixing alternate.
6. Understanding the importance of feedback mechanisms and the role of biogeochemistry when lakes shift in mixing regime could lead to a better understanding of how climate change affects lake ecosystems.

中文翻译：

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内部反馈在变暖气候下改变深湖混合状态中的作用

1. 气候变暖正在引起深湖物理的变化，例如较长的夏季分层，增加的水柱稳定性，减少的冰盖以及较浅的冬季倾覆深度。变暖的最终结果将是过渡到不同的混合方式。在这里，我们研究了在混合机制转变期间展开的物理，化学和生物反馈机制的作用，以及这些反馈是否能够促进和稳定新机制。尽管气候，年际温度变化和湖泊形态是决定混合状态的主要因素，但是当气候变化导致混合状态发生变化时，内部反馈机制可能会变得很重要并改变湖泊生态系统的功能。
2. 我们回顾了这些反馈在三种混合体制转变中的作用：从多学科到季节性分层，从二学科到单学科，从整体论到寡聚或铁素体。
3. 中间深度（复成分湖泊Ç 3-10米平均深度）可能会经历季节性分层如果分层事件触发器浮游植物增殖或溶解的有机物质的释放，从而减少的透明度，因此进一步加热该表面层。但是，这种反馈仅可能在小而清澈的湖泊中产生影响，很容易受到天气条件的干扰，并且由于冬天会分层，因此分层的状态长期不会保持稳定。
4. 在足够深（平均深度为50 m或更多）的湖泊中，冰反照率的反馈可能会导致从覆冰的（模拟的）冬季加速到无冰的（模拟的）冬季，那里的温度记忆从一个冬天转移到另一个冬天。 。然而，关于这个过程是否可以在自然天气变化过程中持续并克服自我稳定机制（如雪热隔离）的争论仍在不断。大多数研究表明，从突然到单相的逐渐过渡比突然过渡的可能性更大。
5. 如果由于不完全混合而引发缺氧，并且由于溶质的积累而使深水密度增加，而由于低铁加热导致密度降低，则可能会发生从完整的向完全孤立的转变。向混合生殖的转变将极大地改变湖泊的生物学，并且可能难以逆转。如果溶质仅在次层层积聚，则形成寡聚状态，在这种状态下，完全混合和不完全混合会交替进行。
6. 了解湖泊混合过程中转移时反馈机制的重要性以及生物地球化学的作用，可以使人们更好地了解气候变化如何影响湖泊生态系统。