Université Côte d'Azur, CNRS, ECOSEAS, Nice, France.
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-Mer, France.
Sci Rep. 2022 Oct 27;12(1):18103. doi: 10.1038/s41598-022-22845-2.
Marine forests are shrinking globally due to several anthropogenic impacts including climate change. Forest-forming macroalgae, such as Cystoseira s.l. species, can be particularly sensitive to environmental conditions (e.g. temperature increase, pollution or sedimentation), especially during early life stages. However, not much is known about their response to the interactive effects of ocean warming (OW) and acidification (OA). These drivers can also affect the performance and survival of crustose coralline algae, which are associated understory species likely playing a role in the recruitment of later successional species such as forest-forming macroalgae. We tested the interactive effects of elevated temperature, low pH and species facilitation on the recruitment of Cystoseira compressa. We demonstrate that the interactive effects of OW and OA negatively affect the recruitment of C. compressa and its associated coralline algae Neogoniolithon brassica-florida. The density of recruits was lower under the combinations OW and OA, while the size was negatively affected by the temperature increase but positively affected by the low pH. The results from this study show that the interactive effects of climate change and the presence of crustose coralline algae can have a negative impact on the recruitment of Cystoseira s.l. species. While new restoration techniques recently opened the door to marine forest restoration, our results show that the interactions of multiple drivers and species interactions have to be considered to achieve long-term population sustainability.
由于气候变化等多种人为因素的影响，海洋森林在全球范围内正在缩小。形成森林的大型藻类，如 Cystoseira s.l. 物种，对环境条件（例如温度升高、污染或沉积）可能特别敏感，尤其是在早期生命阶段。然而，对于它们对海洋变暖（OW）和酸化（OA）的交互作用的响应，我们知之甚少。这些驱动因素还会影响到皮层珊瑚藻的表现和生存，皮层珊瑚藻是一种林下物种，可能在森林形成的大型藻类等后续演替物种的繁殖中发挥作用。我们测试了高温、低 pH 值和物种促进作用对 Cystoseira compressa 繁殖的交互影响。我们证明，OW 和 OA 的交互作用对 C. compressa 和其相关的珊瑚藻 Neogoniolithon brassica-florida 的繁殖产生负面影响。OW 和 OA 组合下的幼苗密度较低，而温度升高会对其大小产生负面影响，但低 pH 值会对其大小产生积极影响。本研究的结果表明，气候变化的交互作用和皮层珊瑚藻的存在可能对 Cystoseira s.l. 物种的繁殖产生负面影响。虽然最近的新技术为海洋森林恢复开辟了道路，但我们的研究结果表明，必须考虑多个驱动因素和物种相互作用的相互作用，以实现长期的种群可持续性。
