Performance and fitness consequences of hypoxia and thermal stress in fishes

环境压力，无论是自然或人为引起的，可能会限制当地的适应，如果人口下降，没有足够的时间来适应，或者如果减少捕食/竞争允许人口持续存在，尽管对当地条件的适应不良。缺氧（低溶解氧，DO）是一种严重的和广泛的表现人为应力内陆和沿海沃茨驱动的废物和化肥的涌入，加速富营养化和污染。在严重缺氧的情况下，氧气可能是一个强大的限制因素，对健身相关的性能特征，如耐力游泳或逃避捕食者。气候变化可能会加剧缺氧对鱼类的影响，因为随着温度的升高，氧的溶解度降低，而外温动物（冷血生物）的代谢增加。相反，缺氧可能会加剧热应力限制有氧性能在较高的温度。

Environmental stress, whether natural or human-induced, may constrain local adaptation if populations decline, have not had sufficient time to adapt, or if reduced predation/competition allows populations to persist despite poor adaptation to local conditions. Hypoxia (low dissolved oxygen, DO) is a serious and widespread manifestation of anthropogenic stress to inland and coastal waters driven by influx of wastes and fertilizers that accelerate eutrophication and pollution. Under severe hypoxia, oxygen can be a powerful limiting factor on fitness-related performance traits, such as endurance swimming or escaping predators. Climate change is likely to exacerbate the impacts of hypoxia on fishes, because oxygen solubility decreases with rising temperature while metabolism of ectotherms (cold-blooded organisms) increases. Conversely, hypoxia may exacerbate thermal stress by limiting aerobic performance at higher temperatures.