Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, Fujian Normal University, Fuzhou, 350007, China.
School of Geographical Sciences, Fujian Normal University, Fuzhou, China.
Microb Ecol. 2023 Aug;86(2):1096-1106. doi: 10.1007/s00248-022-02124-3. Epub 2022 Oct 18.
Global climate change is characterized by altered global atmospheric composition, including elevated CO and O, with important consequences on soil fungal communities. However, the function and community composition of soil fungi in response to elevated CO together with elevated O in paddy soils remain largely unknown. Here we used twelve open-top chamber facilities (OTCs) to evaluate the interactive effect of CO (+ 200 ppm) and O (+ 40 ppb) on the diversity, gene abundance, community structure, and functional composition of soil fungi during the growing seasons of two rice cultivars (Japonica, Wuyujing 3 vs. Nangeng 5055) in a Chinese paddy soil. Elevated CO and O showed no individual or combined effect on the gene abundance or relative abundance of soil fungi, but increased structural complexity of soil fungal communities, indicating that elevated CO and/or O promoted the competition of species-species interactions. When averaged both cultivars, elevated CO showed no individual effect on the diversity or abundance of functional guilds of soil fungi. By contrast, elevated O significantly reduced the relative abundance and diversity of symbiotrophic fungi by an average of 47.2% and 39.1%, respectively. Notably, elevated O exerts stronger effects on the functional processes of fungal communities than elevated CO. The structural equation model revealed that elevated CO and/or O indirectly affected the functional composition of soil fungi through community structure and diversity of soil fungi. Root C/N and soil environmental parameters were identified as the top direct predictors for the community structure of soil fungi. Furthermore, significant correlations were identified between saprotrophic fungi and root biomass, symbiotrophic fungi and root carbon, the pathotroph-symbiotroph and soil pH, as well as pathotroph-saprotroph-symbiotroph and soil microbial biomass carbon. These results suggest that climatic factors substantially affected the functional processes of soil fungal, and threatened soil function and food production, highlighting the detrimental impacts of high O on the function composition of soil biota.
全球气候变化的特征是全球大气成分发生改变，包括 CO 和 O 浓度升高，这对土壤真菌群落产生了重要影响。然而，在稻田土壤中，CO 升高与 O 升高共同作用下土壤真菌的功能和群落组成在很大程度上仍不清楚。在这里，我们使用了 12 个开顶式气室（OTCs）来评估 CO（+200 ppm）和 O（+40 ppb）在两个水稻品种（粳稻，武育粳 3 号与南粳 5055）的生长季节对土壤真菌多样性、基因丰度、群落结构和功能组成的互作影响。CO 升高和 O 升高对土壤真菌的基因丰度或相对丰度均没有单独或综合影响，但增加了土壤真菌群落的结构复杂性，表明 CO 升高和/或 O 升高促进了种间竞争。当平均两种栽培品种时，CO 升高对土壤真菌功能类群的多样性或丰度没有单独的影响。相比之下，O 升高平均分别使共生真菌的相对丰度和多样性降低了 47.2%和 39.1%。值得注意的是，O 升高对真菌群落的功能过程的影响比 CO 升高更强。结构方程模型表明，CO 升高和/或 O 升高通过土壤真菌的群落结构和多样性间接影响土壤真菌的功能组成。根 C/N 和土壤环境参数被确定为土壤真菌群落的顶级直接预测因子。此外，还鉴定出了腐生真菌与根生物量、共生真菌与根碳、病原体-共生体与土壤 pH 以及病原体-腐生菌-共生体与土壤微生物生物量碳之间的显著相关性。这些结果表明，气候因素显著影响了土壤真菌的功能过程，并威胁到土壤功能和粮食生产，突出了高 O 对土壤生物区系功能组成的有害影响。
