Microbiology Department, University of Massachusetts, Amherst, MA, United States of America.
INRAE, AgroParisTech, UMR EcoSys, Université Paris-Saclay, Palaiseau, France.
PLoS One. 2024 Oct 24;19(10):e0311364. doi: 10.1371/journal.pone.0311364. eCollection 2024.
Across biomes, soil biodiversity promotes ecosystem functions. However, whether this relationship will be maintained within ecosystems under climate change is uncertain. Here, using two long-term soil warming experiments, we investigated how warming affects the relationship between ecosystem functions and bacterial diversity across seasons, soil horizons, and warming duration. Soils were sampled from these warming experiments located at the Harvard Forest Long-Term Ecological Research (LTER) site, where soils had been heated +5°C above ambient for 13 or 28 years at the time of sampling. We assessed seven measurements representative of different ecosystem functions and nutrient pools. We also surveyed bacterial community diversity. We found that ecosystem function was significantly affected by season, with autumn samples having a higher intercept than summer samples in our model, suggesting a higher overall baseline of ecosystem function in the fall. The effect of warming on bacterial diversity was similarly affected by season, where warming in the summer was associated with decreased bacterial evenness in the organic horizon. Despite the decreased bacterial evenness in the warmed plots, we found that the relationship between ecosystem function and bacterial diversity was unaffected by warming or warming duration. Our findings highlight that season is a consistent driver of ecosystem function as well as a modulator of climate change effects on bacterial community evenness.
在生物群落中，土壤生物多样性促进了生态系统功能。然而，在气候变化下，这种关系是否能在生态系统中得以维持尚不确定。在这里，我们利用两个长期的土壤增温实验，调查了增温如何影响不同季节、土壤层次和增温持续时间下，生态系统功能与细菌多样性之间的关系。这些增温实验是在哈佛森林长期生态研究（LTER）站点进行的，增温实验在采样时已经将土壤温度比环境温度升高了+5°C，增温持续了 13 年或 28 年。我们评估了七个代表不同生态系统功能和养分库的测量指标。我们还调查了细菌群落多样性。我们发现，生态系统功能受到季节的显著影响，在我们的模型中，秋季样本的截距高于夏季样本，这表明秋季生态系统功能的总体基线更高。增温对细菌多样性的影响也受到季节的影响，夏季的增温与有机层中细菌均匀度的降低有关。尽管增温处理区的细菌均匀度降低，但我们发现，生态系统功能与细菌多样性之间的关系不受增温和增温持续时间的影响。我们的研究结果表明，季节是生态系统功能的一个一致驱动因素，也是气候变化对细菌群落均匀度影响的调节因素。
