Luo Gongwen, Xue Chao, Jiang Qianhong, Xiao Yan, Zhang Fengge, Guo Shiwei, Shen Qirong, Ling Ning
Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China.
College of Agro-Grassland Science, Nanjing Agricultural University, Nanjing, China.
mSystems. 2020 Jun 30;5(3):e00162-20. doi: 10.1128/mSystems.00162-20.
Maintaining stability of ecosystem functions in the face of global change calls for a better understanding regulatory factors of functionally specialized microbial groups and their population response to disturbance. In this study, we explored this issue by collecting soils from 54 managed ecosystems in China and conducting a microcosm experiment to link disturbance, elemental stoichiometry, and genetic resistance. Soil carbon:nitrogen:phosphorus (C:N:P) stoichiometry imparted a greater effect on the abundance of microbial groups associated with main C, N, and P biogeochemical processes in comparison with mean annual temperature and precipitation. Nitrogen cycling genes, including bacterial , , , and , exhibited the highest genetic resistance to N deposition. The and genes exhibited the highest resistance to warming and drying-wetting cycles, respectively. Soil total C, N, and P contents and their ratios had a strong direct effect on the genetic resistance of microbial groups, which was dependent on mean annual temperature and precipitation. Specifically, soil C/P ratio was the main predictor of N cycling genetic resistance to N deposition. Soil total C and N contents and their ratios were the main predictors of P cycling genetic resistance to N deposition, warming, and drying-wetting. Overall, our work highlights the importance of soil stoichiometric balance for maintaining the ability of ecosystem functions to withstand global change. To be effective in predicting future stability of soil functions in the context of various external disturbances, it is necessary to follow the effects of global change on functionally specialized microbes related to C and nutrient cycling. Our study represents an exploratory effort to couple the stoichiometric drivers to microbial populations related with main C, N, and P cycling and their resistances to global change. The abundance of microbial groups involved in cellulose, starch, and xylan degradation, nitrification, N fixation, denitrification, organic P mineralization, and inorganic P dissolution showed a high stoichiometry dependency. Resistance of these microbial populations to global change could be predicted by soil C:N:P stoichiometry. Our work highlights that stoichiometric balance in soil C and nutrients is instrumental in maintaining the stability and adaptability of ecosystem functions under global change.
面对全球变化，维持生态系统功能的稳定性需要更好地理解功能专业化微生物群落的调控因素及其种群对干扰的响应。在本研究中，我们通过收集中国54个管理生态系统的土壤并进行微观实验，将干扰、元素化学计量和遗传抗性联系起来，探讨了这个问题。与年平均温度和降水量相比，土壤碳：氮：磷（C:N:P）化学计量对与主要碳、氮和磷生物地球化学过程相关的微生物群落丰度影响更大。包括细菌的 、 、 和 在内的氮循环基因对氮沉降表现出最高的遗传抗性。 和 基因分别对变暖和干湿循环表现出最高的抗性。土壤总碳、氮和磷含量及其比率对微生物群落的遗传抗性有很强的直接影响，这取决于年平均温度和降水量。具体而言，土壤C/P比率是氮循环对氮沉降遗传抗性的主要预测指标。土壤总碳和氮含量及其比率是磷循环对氮沉降、变暖和干湿作用遗传抗性的主要预测指标。总体而言，我们的工作强调了土壤化学计量平衡对于维持生态系统功能抵御全球变化能力的重要性。为了有效预测在各种外部干扰情况下土壤功能的未来稳定性，有必要跟踪全球变化对与碳和养分循环相关的功能专业化微生物的影响。我们的研究是一项探索性工作，旨在将化学计量驱动因素与与主要碳、氮和磷循环相关的微生物种群及其对全球变化的抗性联系起来。参与纤维素、淀粉和木聚糖降解、硝化作用、固氮作用、反硝化作用、有机磷矿化和无机磷溶解的微生物群落丰度表现出高度的化学计量依赖性。这些微生物种群对全球变化的抗性可以通过土壤C:N:P化学计量来预测。我们的工作强调，土壤碳和养分的化学计量平衡有助于维持全球变化下生态系统功能的稳定性和适应性。
