The mixing and stratification present under ice‐covered lakes during winter can potentially influence the oxygen concentrations in the subsequent spring. During winter, plankton rely on updrafts caused by convection to remain in the photic zone and perform primary production. Thus, there is a crucial link in winter between under‐ice light levels, circulation, and dissolved oxygen (DO) production. Detailed observations of temperature, oxygen, and incoming solar radiation over three winters between 2015 and 2017 suggested that plankton abundance and DO concentrations were maximal near the end of the winter before the ice melted when there was increased under‐ice light and convection. DO was supersaturated by the end of the severe winter of 2015 when the ice cover duration was the longest. In comparison, DO increased but was not saturated in the warmer winters of 2016 and 2017. The spring overturn started when the water column became isothermal and continued until when the mean water column temperature first exceeded 4°C, at which time, hypolimnetic DO depletion started and continued until the fall overturn. The concentration of DO when the water column becomes stratified in spring, along with the timing of the end of spring overturn, are both important initial conditions for summer DO concentrations.

中文翻译：

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大湖区冬季冰湖下的混合，分层和浮游生物：对春季溶解氧水平的影响

冬季，冰雪覆盖的湖泊下的混合和分层可能会影响随后春季的氧气浓度。在冬季，浮游生物依靠对流引起的上升气流停留在光合带并进行初级生产。因此，冬天的冰底光线水平，循环和溶解氧（DO）的产生之间有着至关重要的联系。在2015年至2017年的三个冬季中，对温度，氧气和太阳辐射的详细观测表明，当冰底光线和对流增加时，在冰融化之前的冬季末，浮游生物的丰度和DO浓度最大。到2015年严冬结束时，DO才变得过饱和，当时冰盖的时间最长。相比下，DO升高，但在2016年和2017年的较温暖的冬天并未饱和。当水柱达到等温状态时，春季翻转开始，并一直持续到平均水柱温度首次超过4°C时，此时低铁溶解氧开始并持续直到秋天倾覆。春季水柱分层时的溶解氧浓度以及春季翻转结束的时间，都是夏季溶解氧浓度的重要初始条件。