Schertenleib Katrin S H, Davey Tallulah, Taylor David, O'Connor Nessa E
Discipline of Zoology School of Natural Sciences, Trinity College Dublin Dublin 2 Ireland.
Department of Mechanical, Manufacturing and Biomedical Engineering School of Engineering, Trinity College Dublin Dublin 2 Ireland.
Ecol Evol. 2024 Sep 18;14(9):e70308. doi: 10.1002/ece3.70308. eCollection 2024 Sep.
The effects of climate change on coastal biodiversity are a major concern because altered community compositions may change associated rates of ecosystem functioning and services. Whilst responses of single species or taxa have been studied extensively, it remains challenging to estimate responses to climate change across different levels of biological organisation. Studies that consider the effects of moderate realistic near-future levels of ocean warming and acidification are needed to identify and quantify the gradual responses of species to change. Also, studies including different levels of biological complexity may reveal opportunities for amelioration or facilitation under changing environmental conditions. To test experimentally for independent and combined effects of predicted near-future warming and acidification on key benthic species, we manipulated three levels of temperature (winter ambient, +0.8 and +2°C) and two levels of pco (ambient at 450 ppm and elevated at 645 ppm) and quantified their effects on mussels and algae growing separately and together (to also test for inter-specific interactions). Warming increased mussel clearance and mortality rates simultaneously, which meant that total biomass peaked at +0.8°C. Surprisingly, however, no effects of elevated pco were identified on mussels or algae. Moreover, when kept together, mussels and algae had mutually positive effects on each other's performance (i.e. mussel survival and condition index, mussel and algal biomass and proxies for algal productivity including relative maximum electron transport rate [rETRmax], saturating light intensity [ ] and maximum quantum yield [ / ]), independent of warming and acidification. Our results show that even moderate warming affected the functioning of key benthic species, and we identified a level of resistance to predicted ocean acidification. Importantly, we show that the presence of a second functional group enhanced the functioning of both groups (mussels and algae), independent of changing environmental conditions, which highlights the ecological and potential economic benefits of conserving biodiversity in marine ecosystems.
气候变化对沿海生物多样性的影响是一个主要关注点，因为群落组成的改变可能会改变生态系统功能和服务的相关速率。虽然对单一物种或分类群的反应已经进行了广泛研究，但估计不同生物组织水平对气候变化的反应仍然具有挑战性。需要开展研究，考虑近期海洋变暖和酸化的适度现实水平的影响，以识别和量化物种对变化的渐进反应。此外，纳入不同生物复杂性水平的研究可能会揭示在不断变化的环境条件下改善或促进的机会。为了通过实验测试近期预测的变暖和酸化对关键底栖物种的独立和综合影响，我们控制了三个温度水平（冬季环境温度、+0.8和+2°C）和两个pco₂水平（450 ppm的环境水平和645 ppm的升高水平），并量化了它们对单独生长和共同生长的贻贝和藻类的影响（同时也测试种间相互作用）。变暖同时提高了贻贝的滤食率和死亡率，这意味着总生物量在+0.8°C时达到峰值。然而，令人惊讶的是，未发现pco₂升高对贻贝或藻类有影响。此外，当贻贝和藻类共同培养时，它们对彼此生长表现具有相互积极影响（即贻贝存活率和状况指数、贻贝和藻类生物量以及藻类生产力指标，包括相对最大电子传递速率[rETRmax]、饱和光强[ ]和最大量子产量[ / ]），且不受变暖和酸化影响。我们的结果表明，即使是适度变暖也会影响关键底栖物种的功能，并且我们确定了对预测海洋酸化的一定抗性水平。重要的是，我们表明第二个功能组的存在增强了两组（贻贝和藻类）的功能，且不受环境条件变化的影响，这凸显了保护海洋生态系统生物多样性的生态和潜在经济效益。
