Negative Effects of Diurnal Changes in Acidification and Hypoxia on Early-Life Stage Estuarine Fishes
Negative Effects of Diurnal Changes in Acidification and Hypoxia on Early-Life Stage Estuarine Fishes
复制标题
酸化和缺氧的日变化对生命早期河口鱼类的负面影响
DOI：
10.3390/d12010025
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
C. Gobler
中科院分区：
文献类型：
--
作者：
Brooke K. Morrell;C. Gobler
河口是各种早期鱼类的重要育苗栖息地，但可能会同时经历酸化和缺氧，其强度可能每天不同。研究了酸化(pH 7.2-7.4)和低氧(溶解氧(DO)~2-4 mg L−1)作为单独应激源和复合应激源对美国东海岸特有的3种饲用鱼类4种适合度的影响。此外，还评估了暴露于这两种应激源的不同持续时间的影响，以探索在具有环境代表性的条件下仔鱼的敏感阈值。杂色梭子蟹对慢性低pH值具有抵抗力，而门氏支原体和贝氏支原体的存活率和孵化时间分别显著减少。暴露在低氧环境中会导致两种膜亚目幼虫的孵化成功率降低，以及贝氏沼虾幼虫的存活率降低。每天暴露在低pH和低DO下4或8h并不能改变贝雷利纳幼虫的存活率，但每天暴露8h或12h可显著抑制幼虫的大小。相反，在缺氧和酸化的所有周期内(4-12小时)，门静脉分枝杆菌的存活率都显著下降。暴露在12小时的昼夜低氧环境中，尽管平均DO暴露浓度明显高于相同水平的低氧暴露，但通常会引起与长期低氧暴露相同或更严重的负面影响。这证明了适应不断变化的DO水平需要付出大量的生物学成本，并暗示DO的昼夜循环是对河口鱼类幼体的重大威胁。在这项研究中，幼体对缺氧的反应，以及对酸化程度较小的反应，在连续和每天的时间尺度上都表明，整个产卵和产卵后时期的河口条件可能对这些鱼类的种群产生不利影响，对食物网的其余部分产生不同的影响。
Estuaries serve as important nursery habitats for various species of early-life stage fish, but can experience cooccurring acidification and hypoxia that can vary diurnally in intensity. This study examines the effects of acidification (pH 7.2–7.4) and hypoxia (dissolved oxygen (DO) ~ 2–4 mg L−1) as individual and combined stressors on four fitness metrics for three species of forage fish endemic to the U.S. East Coast: Menidia menidia, Menidia beryllina, and Cyprinodon variegatus. Additionally, the impacts of various durations of exposure to these two stressors was also assessed to explore the sensitivity threshold for larval fishes under environmentally-representative conditions. C. variegatus was resistant to chronic low pH, while M. menidia and M. beryllina experienced significantly reduced survival and hatch time, respectively. Exposure to hypoxia resulted in reduced hatch success of both Menidia species, as well as diminished survival of M. beryllina larvae. Diurnal exposure to low pH and low DO for 4 or 8 h did not alter survival of M. beryllina, although 8 or 12 h of daily exposure through the 10 days posthatch significantly depressed larval size. In contrast, M. menidia experienced significant declines in survival for all intervals of diel cycling hypoxia and acidification (4–12 h). Exposure to 12-h diurnal hypoxia generally elicited negative effects equal to, or of greater severity, than chronic exposure to low DO at the same levels despite significantly higher mean DO exposure concentrations. This evidences a substantial biological cost to adapting to changing DO levels, and implicates diurnal cycling of DO as a significant threat to fish larvae in estuaries. Larval responses to hypoxia, and to a lesser extent acidification, in this study on both continuous and diurnal timescales indicate that estuarine conditions throughout the spawning and postspawn periods could adversely affect stocks of these fish, with diverse implications for the remainder of the food web.
影响因子：
2.7
作者：
Baumann, Hannes;Smith, Erik M.
通讯作者：
Smith, Erik M.
你最好重复一遍：系列实验揭示了复杂的二氧化碳和温度对大西洋银边后代的影响
DOI：
10.3390/d10030069
发表时间：
2018
期刊：
Diversity
影响因子：
--
作者：
Murray, Christopher;Baumann, Hannes
通讯作者：
Baumann, Hannes