Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China.
College of Chemistry and Life Sciences, Chengdu Normal University, Chengdu 611130, PR China.
J Environ Manage. 2022 Oct 1;319:115683. doi: 10.1016/j.jenvman.2022.115683. Epub 2022 Jul 17.
Soil ecosystem functions and microbial community structure were severely impaired with long-term cadmium (Cd) contamination and acidification. To investigate the effect of amendments on soil physiochemical parameters and soil micro-ecology in acidic Cd contaminated soil, this study was conducted in a pot experiment with the application of calcium amendments, oyster shell powders (OS) and limestone (LM). Each amendment applied at ratios of 1.0%, 3.0%, and 5.0% (w/w), respectively. The results showed that the application of amendments increased the soil pH by 2.10-2.88, the bioavailable Cd decreased by 12.49%-19.48%, and un-bioavailable Cd increased by 96.57%-200.7%. The OS increased the richness index (Chao and Ace increased by 13.23%-16.20% and 7.13%-47.63%), and LM increased the microbial diversity index (Shannon increased by 1.14%-8.72% and Simpson indexes decreased by 28.00%-63.61%). In LM groups, soil microbial communities were significantly altered with increasing application concentrations, the relative abundance of phylum Proteobacteria, Bacteroidota and Gemmatimonadota increased, while Firmicute, Actinobacteria, Chloroflexi decreased. In OS treatments, the soil microbial community structure was basically unchanged. The correlation analysis showed that pH, TN, TP, CEC, OM were the dominant factors affecting the microbial community. This study has shown that application of amendments could effectively reduce the Cd bioavailability in soil, but LM altered the soil microbial community structure, while OS maintained the soil microbiological structure.
长期镉（Cd）污染和酸化会严重破坏土壤生态系统功能和微生物群落结构。为了研究改良剂对酸性 Cd 污染土壤理化参数和土壤微生态的影响，本研究采用盆栽试验，应用钙改良剂、牡蛎壳粉（OS）和石灰石（LM）。每种改良剂的添加比例分别为 1.0%、3.0%和 5.0%（w/w）。结果表明，施用改良剂可使土壤 pH 值提高 2.10-2.88，有效态 Cd 降低 12.49%-19.48%，无效态 Cd 增加 96.57%-200.7%。OS 增加了丰富度指数（Chao 和 Ace 分别增加了 13.23%-16.20%和 7.13%-47.63%），LM 增加了微生物多样性指数（Shannon 增加了 1.14%-8.72%，Simpson 指数降低了 28.00%-63.61%）。在 LM 组中，随着施用量的增加，土壤微生物群落发生了显著变化，厚壁菌门、拟杆菌门和芽单胞菌门的相对丰度增加，而Firmicutes、Actinobacteria、Chloroflexi 减少。在 OS 处理中，土壤微生物群落结构基本不变。相关分析表明，pH、TN、TP、CEC、OM 是影响微生物群落的主要因素。本研究表明，施用改良剂可有效降低土壤中 Cd 的生物有效性，但 LM 改变了土壤微生物群落结构，而 OS 维持了土壤微生物结构。
