Effects of acidification and nitrate eutrophication on the widespread soft coral Xenia umbellata

Coral reefs may experience lower pH values as a result of ocean acidification, which has negative consequences for many reef organisms and may be exacerbated by other factors such as eutrophication. Thus far, the effects of these global (acidification) and local (eutrophication) factors have been mainly investigated separately, and previous research concentrated on hard corals. We thus carried out a manipulative aquarium experiment for 21 days to study the response of the widespread pulsating soft coral Xenia umbellata to ocean acidification (stepwise decrease from ambient (8.2) to pH values of 8.0, 7.8, and 7.6) and nitrogen eutrophication, i.e., nitrate concentrations were increased from ambient (< 0.5 µM) to ~5 µM. […]

珊瑚礁可能因海洋酸化而出现较低的pH值，这对于众多珊瑚礁生物构成了负面影响，且这一影响可能因富营养化等其他因素而加剧。迄今为止，全球性（酸化）与局部性（富营养化）因素的作用主要被分别研究，而以往的研究主要集中在硬珊瑚上。因此，我们进行了一项为期21天的操纵性水族箱实验，旨在探究广泛分布的脉动软珊瑚伞珊瑚（Xenia umbellata）对海洋酸化（从环境中的（8.2）逐步降低至pH值8.0、7.8和7.6）及氮富营养化（即硝酸根浓度从环境中的（<0.5 µM）增加到约5 µM）的响应。