Abstract Ocean acidification (OA) influences the production of volatile organic compounds (VOCs) by seagrass leaves and their associated epiphytes. We hypothesize that the perception of “odour” produced by seagrass leaf epiphytes will change with seawater acidification, affecting the behaviour of seagrass-associated invertebrates. To test this hypothesis, we collected epiphytes from leaves of Posidonia oceanica growing at two pH conditions (7.7 and 8.1) and identified the most abundant genera of diatoms. We tested the VOCs produced at pH 8.1 by the epiphytic communities in toto, as well as those produced by selected diatoms, on various invertebrates. A complex set of species-specific and concentration-dependent chemotactic reactions was recorded, according to the pH of seawater. In particular, VOCs produced by individual diatoms triggered contrasting reactions in invertebrates, depending on the pH. The perception of epiphyte VOCs is likely to vary due to alteration of species ability to perceive and/or interpret chemical cues as infochemicals or due to changes in the structure of VOCs themselves. Thus, OA alters the fine-tuned chemical cross-talks between seagrass epiphytes and associated invertebrates, with potential consequences for the structure of communities and food webs of seagrass ecosystems.

中文翻译：

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海洋酸化改变了无脊椎动物对海草 Posidonia Oceanica 附生植物产生的伤口激活信息化学物质的反应

摘要 海洋酸化 (OA) 会影响海草叶片及其相关附生植物产生的挥发性有机化合物 (VOC)。我们假设海草叶附生植物对“气味”的感知会随着海水酸化而改变，从而影响与海草相关的无脊椎动物的行为。为了验证这一假设，我们从在两种 pH 条件（7.7 和 8.1）下生长的 Posidonia Oceanica 的叶子中收集了附生植物，并确定了最丰富的硅藻属。我们在各种无脊椎动物上测试了附生群落在 pH 8.1 下产生的 VOC，以及由选定的硅藻产生的 VOC。根据海水的 pH 值，记录了一组复杂的物种特异性和浓度依赖性趋化反应。特别是，由单个硅藻产生的 VOC 会在无脊椎动物中引发对比反应，具体取决于 pH 值。由于物种将化学线索感知和/或解释为信息化学物质的能力的改变或由于 VOC 本身结构的变化，对附生植物 VOC 的感知可能会有所不同。因此，OA 改变了海草附生植物和相关无脊椎动物之间微调的化学串扰，对海草生态系统的群落结构和食物网产生潜在影响。