Li Yan, Ge Yuan, Wang Jichen, Shen Congcong, Wang Jianlei, Liu Yong-Jun
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
Mol Ecol. 2021 Jun;30(12):2915-2930. doi: 10.1111/mec.15935. Epub 2021 May 18.
Observational and experimental evidence has revealed the functional importance of microbial diversity. However, the effects of microbial diversity loss on ecosystem functions are not consistent across studies, which are probably tempered by microbial functional redundancy, specific taxa and functions evaluated. Here we conducted diversity manipulation experiments in two independent soils with distinct prokaryotic communities, and investigated how the initial community traits (e.g., distinct functional redundancy and taxonomic composition) modulate the contribution of prokaryotic diversity loss and composition shift to eight ecosystem functions related to soil nutrient cycling. We found that diversity loss impaired three functions (potential nitrification rate, N -fixation activity and phosphatase) and multifunctionality only in the communities with low functional redundancy, but all examined functions were unaffected in the communities with high functional redundancy. All significantly affected functions belonged to specialized functions, while the broad function (soil basal respiration) was unaffected. Moreover, prokaryotic composition explained more functional variation than diversity, which was ascribed to the crucial role of specific taxa that influence particular functions. Taken together, this study provides empirical evidence for identifying the mechanism underlying the ecosystem response to changes in microbial community, with implications for improving the prediction of ecosystem process models and managing microbial communities to promote ecosystem services.
观察和实验证据揭示了微生物多样性的功能重要性。然而，微生物多样性丧失对生态系统功能的影响在各项研究中并不一致，这可能受到微生物功能冗余、所评估的特定分类群和功能的影响。在此，我们在具有不同原核生物群落的两种独立土壤中进行了多样性操纵实验，并研究了初始群落特征（例如，不同的功能冗余和分类组成）如何调节原核生物多样性丧失和组成变化对与土壤养分循环相关的八种生态系统功能的贡献。我们发现，多样性丧失仅在功能冗余度低的群落中损害了三种功能（潜在硝化速率、固氮活性和磷酸酶）以及多功能性，但在功能冗余度高的群落中，所有检测的功能均未受影响。所有受到显著影响的功能都属于特定功能，而广泛功能（土壤基础呼吸）未受影响。此外，原核生物组成比多样性解释了更多的功能变异，这归因于影响特定功能的特定分类群的关键作用。综上所述，本研究为确定生态系统对微生物群落变化作出响应的潜在机制提供了实证依据，对改进生态系统过程模型的预测以及管理微生物群落以促进生态系统服务具有重要意义。
