研究报告
施昊坤,吴次芳,胡一鸣,林耀奔.土地整治对盐碱土壤细菌群落动态和组装的影响分析[J].环境科学学报,2023,43(2):317-329
土地整治对盐碱土壤细菌群落动态和组装的影响分析
- Land consolidation impacted edaphic bacterial community dynamics and assembly in saline alkali land
- 基金项目:国家社会科学基金重大项目(No.14ZDA039)
- 林耀奔
- 南京工业大学法律与公共事务学院,南京211899
- 摘要:了解土地整治对盐碱土壤细菌群落的影响对认识盐碱地生态特征和推动生态修复具有重要意义.以黄河三角洲盐碱土壤为研究对象,利用Illumina高通量测序技术,测定土地整治区与非整治区土壤细菌群落结构差异,并分析了土壤环境变量、空间因子和土地整治行为对细菌群落结构的相对贡献,探讨了土地整治对细菌群落组装和细菌群落功能的影响.结果表明:土地整治区仅有Shannon多样性指数显著高于非整治区.土地整治区与非整治区的细菌群落结构存在显著差异,通过LEfSe分析确定了细菌群落中的生物标志物,这些生物标志物在土地整治区大多与氮循环过程相关,在非整治区则大多表现出对有机污染与重金属污染的耐受性.空间距离效应分析表明土地整治有利于减弱空间因素对细菌群落结构的影响.中性群落模型分析结果显示土地整治区细菌群落的拟合程度更高,表明具有更高的迁移能力.方差分解分析表明环境变量单独解释部分对细菌群落结构变异的贡献率最大(15.50%).细菌功能预测结果表明土地整治区土壤氮循环相关功能显著增强,在非整治区碳降解活动更为活跃.总之,土地整治对细菌群落具有显著影响,降低土壤环境的空间异质性,并能够有效改善细菌群落功能.因此,这些发现有助于为开展盐碱地生态修复提供参考.
- Abstract:Identifying the impacts of land consolidation on bacterial community shift and assembly is of great significance to understand the ecological characteristics of saline-alkali soil and promote efficiency of ecological restoration. Taking saline-alkali soil of cultivation areas in the Yellow River Delta as the study region, we determined the differences of soil bacterial community structure between land consolidation areas and non-consolidation areas by Illumina high-throughput sequencing technology. The contributions of edaphic environmental variables, spatial factors, and land consolidation behavior to the bacterial community composition were analyzed. Additionally, the impacts of land consolidation on the assembly of bacterial communities and bacterial community function were discussed. The results showed that the Shannon diversity index was significantly higher in the areas with land consolidation than that without land consolidation. There are significant differences in bacterial community structure between land consolidation areas and non-consolidation areas. Moreover, we identified some bacterial groups as biomarkers of soil bacterium through LEfSe, and many of them were significantly related to the nitrogen cycle in land consolidation. In contrast, some biomarkers in farmland without land consolidation showed tolerance to organic pollution or heavy metal pollution. The results of geographical distance decay analysis suggested that land consolidation was conducive to weakening the influence of spatial factors on bacterial community structure. The analysis results of the neutral community model indicated that the fitting degree of bacterial community under land consolidation was higher, suggesting that they might have a higher migration. The results of variance partitioning analysis showed that edaphic environmental variables contributed most (15.50%) to the variation of community structure. Moreover, the results of functional prediction indicated that the related functions of soil nitrogen cycle were significantly enhanced by land consolidation, while the carbon degradation activity was more active in areas without land consolidation. In summary, land consolidation can cause significantly effects on bacterial community composition, reduce spatial heterogeneity of the edaphic environment, and improve the nitrogen cycling of the bacterial community. These findings help provide references for ecological restoration of saline-alkali land.