Engineering Research Center of Ministry of Education for Mine Ecological Restoration, Xuzhou 221116, China; School of Environmental Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China.
School of Environmental Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China.
Chemosphere. 2022 Sep;302:134811. doi: 10.1016/j.chemosphere.2022.134811. Epub 2022 May 2.
Cadmium (Cd) pollution cause severe stress to soil microorganisms and biochar utilized for its ability to immobilize Cd in the soil effectively. However, the influence of biochar on the structure and function of the bacterial network under Cd stress is unclear. This research reports a pot experiment conducted to investigate the impact of 2.0% Italian poplar bark biochar (PB), 2.0% thiourea-modified biochar (TP), and control treatment (CK) on the complexity, stability and functional properties of the bacterial community under Cd stress. The results showed that: (1) Biochar increased the diversity of soil bacterial consortia under Cd stress (p < 0.05), and the diversity index demonstrated as order of CK < PB < TP; (2) Compared with CK network, the nodes number of PB and TP treatments networks were much higher, while the modularity and transitivity increased by 0.04% and 37.6%, 2.45% and 1.12%, respectively. The biochar amendment increased the stability and complexity of the network; (3) PICRUSt2 prediction results show that Xenobiotics biodegradation and metabolism membrane transport of TP treatment increased 62.52% and 53.62% compared with CK, respectively, which could be related to the decrease in Cd content according to principal component analysis. (4) The reduction of leaching Cd content caused network complexity and bacterial function changes by biochar amendment. TP amendment enhanced the complexity and stability of soil bacterial community under Cd stress, which will provide a scientific basis for in situ remediations of Cd-contaminated soils.
镉（Cd）污染会对土壤微生物造成严重压力，而生物炭因其有效固定土壤中 Cd 的能力而被广泛应用。然而，生物炭对 Cd 胁迫下细菌网络结构和功能的影响尚不清楚。本研究通过盆栽实验，研究了 2.0%意大利杨树皮生物炭（PB）、2.0%硫脲改性生物炭（TP）和对照处理（CK）对 Cd 胁迫下细菌群落复杂性、稳定性和功能特性的影响。结果表明：（1）生物炭增加了 Cd 胁迫下土壤细菌群落的多样性（p<0.05），多样性指数顺序为 CK<PB<TP；（2）与 CK 网络相比，PB 和 TP 处理网络的节点数明显更高，而模块度和传递性分别增加了 0.04%和 37.6%、2.45%和 1.12%。生物炭的添加增加了网络的稳定性和复杂性；（3）PICRUSt2 预测结果表明，与 CK 相比，TP 处理的 Xenobiotics biodegradation and metabolism membrane transport 分别增加了 62.52%和 53.62%，这可能与主成分分析中 Cd 含量的降低有关；（4）生物炭添加降低了浸出 Cd 含量，从而改变了网络复杂性和细菌功能。TP 添加剂增强了 Cd 胁迫下土壤细菌群落的复杂性和稳定性，为原位修复 Cd 污染土壤提供了科学依据。
