Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & Key Laboratory of Microbiology, College of Heilongjiang Province & School of Life Sciences, Heilongjiang University, Harbin 150080, China.
Griffith School of Environment and Science and the Australian Rivers Institute, Griffith University, Nathan, QLD, Australia.
Sci Total Environ. 2024 Jul 20;935:173286. doi: 10.1016/j.scitotenv.2024.173286. Epub 2024 May 19.
Nitrogen cycling in terrestrial ecosystems is critical for biodiversity, vegetation productivity and biogeochemical cycling. However, little is known about the response of functional nitrogen cycle genes to global change factors in soils under different land uses. Here, we conducted a multiple hierarchical mixed effects meta-analyses of global change factors (GCFs) including warming (W+), mean altered precipitation (MAP+/-), elevated carbon dioxide concentrations (eCO), and nitrogen addition (N+), using 2706 observations extracted from 200 peer-reviewed publications. The results showed that GCFs had significant and different effects on soil microbial communities under different types of land use. Under different land use types, such as Wetland, Tundra, Grassland, Forest, Desert and Agriculture, the richness and diversity of soil microbial communities will change accordingly due to differences in vegetation cover, soil management practices and environmental conditions. Notably, soil bacterial diversity is positively correlated with richness, but soil fungal diversity is negatively correlated with richness, when differences are driven by GCFs. For functional genes involved in nitrification, eCO in agricultural soils and the interaction of N+ with other GCFs in grassland soils stimulate an increase in the abundance of the AOA-amoA gene. In agricultural soil, MAP+ increases the abundance of nifH. W+ in agricultural soils and N+ in grassland soils decreased the abundance of nifH. The abundance of the genes nirS and nirK, involved in denitrification, was mainly negatively affected by W+ and positively affected by eCO in agricultural soil, but negatively affected by N+ in grassland soil. This meta-analysis was important for subsequent research related to global climate change. Considering data limitations, it is recommended to conduct multiple long-term integrated observational experiments to establish a scientific basis for addressing global changes in this context.
陆地生态系统中的氮循环对生物多样性、植被生产力和生物地球化学循环至关重要。然而，对于不同土地利用方式下土壤中功能氮循环基因对全球变化因素的响应，人们知之甚少。在这里，我们对包括增温（W+）、平均改变降水（MAP+/-）、升高二氧化碳浓度（eCO）和氮添加（N+）在内的全球变化因素（GCFs）进行了多层次混合效应荟萃分析，使用了从 200 篇同行评议出版物中提取的 2706 个观测结果。结果表明，GCFs 对不同土地利用类型下的土壤微生物群落有显著的不同影响。在不同的土地利用类型下，如湿地、苔原、草原、森林、沙漠和农业，由于植被覆盖、土壤管理实践和环境条件的差异，土壤微生物群落的丰富度和多样性将相应变化。值得注意的是，当差异由 GCFs 驱动时，土壤细菌多样性与丰富度呈正相关，而土壤真菌多样性与丰富度呈负相关。对于与硝化作用有关的功能基因，农业土壤中的 eCO 和草原土壤中 N+与其他 GCFs 的相互作用刺激 AOA-amoA 基因丰度增加。在农业土壤中，MAP+增加了 nifH 的丰度。农业土壤中的 W+和草原土壤中的 N+降低了 nifH 的丰度。参与反硝化作用的基因 nirS 和 nirK 的丰度主要受 W+的负向影响，受农业土壤中 eCO 的正向影响，但受草原土壤中 N+的负向影响。这项荟萃分析对于随后与全球气候变化相关的研究很重要。考虑到数据的局限性，建议进行多次长期综合观测实验，为解决这方面的全球变化建立科学基础。
