Soil bacterial taxonomic diversity is critical to maintaining the plant productivity
Soil bacterial taxonomic diversity is critical to maintaining the plant productivity
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DOI：
10.1016/j.envint.2020.105766
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发表时间：
2020-07-01
影响因子：
11.8
通讯作者：
Hu, Hang-Wei
中科院分区：
文献类型：
--
作者：
Chen, Qing-Lin;Ding, Jing;Hu, Hang-Wei
土壤微生物群落在驱动多种生态系统功能和生态过程中起着核心作用，这些功能和过程是维持植物生产力的关键。然而，我们缺乏可靠的证据土壤微生物多样性和植物生产力之间的联系，这阻碍了我们的能力，以预测在全球环境变化的背景下，微生物多样性损失的粮食安全的后果。在这里，我们使用的稀释灭绝的方法来测试土壤微生物多样性损失的温室实验中的地上植物生物量的后果。与原始土壤相比，连续稀释接种物处理的细菌α多样性（观察到的操作分类单位和Shannon指数）显着降低。主坐标分析表明，原始土壤中的细菌群落组成（β多样性）与连续稀释接种物的处理明显分离。无论接种与否，原土生菜地上生物量均显著高于灭菌土。普通最小二乘回归模型表明，植物生物量与细菌α多样性之间存在显著的线性关系，表明土壤微生物多样性的降低会导致生菜生物量的显著下降。植物生物量与土壤基础呼吸和反硝化速率之间没有显著的相关性。结构方程模型表明，土壤微生物多样性对植物生物量的影响保持，即使同时占其他驱动程序（土壤特性和生物过程）。我们的研究提供了实验证据，土壤微生物多样性是重要的植物生产力的维持，并建议在土壤微生物群落的功能冗余可能被高估，特别是在农业生态系统。
Soil microbial communities play a central role in driving multiple ecosystem functions and ecological processes that are key to maintaining the plant productivity. However, we lack sound evidence for the linkage between soil microbial diversity and plant productivity, which hinders our ability to predict the consequences of microbial diversity loss for food security under the context of global environmental change. Here, we used the dilution-to-extinction approach to test the consequences of soil microbial diversity loss for the aboveground plant biomass in a glasshouse experiment. Compared with original soils, the bacterial alpha-diversity (Observed operational taxonomic units and Shannon index) significantly decreased in treatments with serially diluted inoculum. Principal coordinates analysis showed that the overall bacterial community compositions (beta-diversity) in original soils were clearly separated from the treatments with serially diluted inoculum. The aboveground biomass of lettuce harvested from the original soils was significantly higher than that from the sterilized soils regardless of the inoculation. The ordinary least squares regression model showed a significant linear relationship between the plant biomass and bacterial alpha-diversity, indicating that reduction in soil microbial diversity could result in a significant decline in the biomass of lettuce. No significant correlation was observed between plant biomass and soil processes including soil basal respiration and denitrification rates. Structural equation models suggested that the effects of soil microbial diversity on the plant biomass were maintained even when simultaneously accounting for other drivers (soil properties and biological processes). Our study provides experimental evidence that soil microbial diversity is important to the maintenance of the plant productivity and suggests that the functional redundancy in soil microbial communities may be overestimated especially in the agroecological system.