Ecosystem metabolism drives pH variability and modulates long-term ocean acidification in the Northeast Pacific coastal ocean
Ecosystem metabolism drives pH variability and modulates long-term ocean acidification in the Northeast Pacific coastal ocean
复制标题
DOI：
10.1038/s41598-018-37764-4
复制
发表时间：
2019-01-30
影响因子：
4.6
通讯作者：
Ruesink, Jennifer
中科院分区：
文献类型：
--
作者：
Lowe, Alexander T.;Bos, Julia;Ruesink, Jennifer
海洋酸化对沿海生态系统服务构成严重威胁，但很少有实证研究调查了当地生态过程如何调节大气CO2上升引起的全球pH值变化。我们量化的模式pH值的变化作为大气中的CO2和当地的物理和生物过程在83个站点超过25年在萨利希海和两个东北太平洋河口的功能。平均海水pH值以-0.009 +/- 0.0005 pH值/年（-1）（25年内pH值为0.22）大幅下降，空间变化率比大气CO2驱动的海洋酸化高10倍。溶解氧饱和度（% DO）每年下降-0.24 +/- 0.036%（-1），特定地点的趋势与pH值相似。平均pH值从< 7.6 in winter to >夏季的8.0变化，伴随着从异养（% DO < 100）到自养（% DO > 100）的季节性变化，以及对成壳生物至关重要的文石饱和状态的急剧变化（冬季不饱和概率> 80%，但夏季< 20%）。% DO压倒了大气CO2、温度和盐度对pH的影响。总的来说，这些观察结果提供了证据，表明当地生态系统过程调节海洋酸化，并支持从生态系统角度看待海洋酸化和生产性水生生境的多种压力。
Ocean acidification poses serious threats to coastal ecosystem services, yet few empirical studies have investigated how local ecological processes may modulate global changes of pH from rising atmospheric CO2. We quantified patterns of pH variability as a function of atmospheric CO2 and local physical and biological processes at 83 sites over 25 years in the Salish Sea and two NE Pacific estuaries. Mean seawater pH decreased significantly at -0.009 +/- 0.0005 pH yr(-1) (0.22 pH over 25 years), with spatially variable rates ranging up to 10 times greater than atmospheric CO2-driven ocean acidification. Dissolved oxygen saturation (% DO) decreased by -0.24 +/- 0.036% yr(-1), with site-specific trends similar to pH. Mean pH shifted from < 7.6 in winter to > 8.0 in summer concomitant to the seasonal shift from heterotrophy (% DO < 100) to autotrophy (% DO > 100) and dramatic shifts in aragonite saturation state critical to shell-forming organisms (probability of undersaturation was > 80% in winter, but < 20% in summer). % DO overwhelmed the influence of atmospheric CO2, temperature and salinity on pH across scales. Collectively, these observations provide evidence that local ecosystem processes modulate ocean acidification, and support the adoption of an ecosystem perspective to ocean acidification and multiple stressors in productive aquatic habitats.