Yu Xiumei, Yan Min, Cui Yongliang, Liu Zhongyi, Liu Han, Zhou Jie, Liu Jiahao, Zeng Lan, Chen Qiang, Gu Yunfu, Zou Likou, Zhao Ke, Xiang Quanju, Ma Menggen, Li Shuangcheng
College of Resources, Sichuan Agricultural University, Chengdu, China.
Sichuan Provincial Academy of Natural Resource Sciences, Chengdu, China.
Front Microbiol. 2022 May 6;12:809834. doi: 10.3389/fmicb.2021.809834. eCollection 2021.
Cadmium pollution is a serious threat to the soil environment. The application of bio-based fertilizers in combination with beneficial microbial agents is a sustainable approach to solving Cd pollution in farm soil. The present study investigated the effects of co-application of a Cd-immobilizing bacterial agent and two fermented organic fertilizers (fermentative edible fungi residue; fermentative cow dung) on and its microbial communities in a Cd-polluted field. It showed that both the application of the Cd-immobilizing bacterial agent alone and the combined application of bio-based soil amendments and the bacterial agent effectively reduced >20% of the uptake of Cd by the plant. Soil nitrogen level was significantly raised after the combined fertilization. The multivariate diversity analysis and co-occurrence network algorithm showed that a significant shift of microbial communities took place, in which the microbial populations tended to be homogeneous with reduced microbial richness and increased diversity after the co-application. The treatment of fermentative cow dung with the addition of the bacterial agent showed a significant increase in the microbial community dissimilarity ( = 0.996, = 0.001) compared to that treated with cow dung alone. The co-application of the bacterial agent with both organic fertilizers significantly increased the abundance of and . The FAPROTAX soil functional analysis revealed that the introduction of the microbial agent could potentially suppress human pathogenic microorganisms in the field fertilized with edible fungi residue. It also showed that the microbial agent can reduce the nitrite oxidation function in the soil when applied alone or with the organic fertilizers. Our study thus highlights the beneficial effects of the Cd-immobilizing bacterial inoculant on and provides a better understanding of the microbial changes induced by the combined fertilization using the microbial agent and organic soil amendments in a Cd-contaminated field.
镉污染对土壤环境构成严重威胁。将生物基肥料与有益微生物剂联合施用是解决农田土壤镉污染的可持续方法。本研究调查了在镉污染农田中，联合施用镉固定菌剂和两种发酵有机肥（发酵食用菌渣；发酵牛粪）对镉吸收及其微生物群落的影响。结果表明，单独施用镉固定菌剂以及生物基土壤改良剂与菌剂联合施用均能有效降低植物对镉的吸收，降幅超过20%。联合施肥后土壤氮含量显著提高。多变量多样性分析和共现网络算法表明，微生物群落发生了显著变化，联合施用后微生物种群趋于同质化，微生物丰富度降低，多样性增加。与单独施用牛粪相比，添加菌剂处理的发酵牛粪微生物群落差异显著增加（ = 0.996， = 0.001）。菌剂与两种有机肥联合施用显著增加了 和 的丰度。FAPROTAX土壤功能分析表明，引入微生物剂可能会抑制食用菌渣施肥农田中的人类致病微生物。研究还表明，单独施用或与有机肥一起施用微生物剂均可降低土壤中的亚硝酸盐氧化功能。因此，我们的研究突出了镉固定菌剂对镉吸收的有益作用，并增进了对镉污染农田中使用微生物剂和有机土壤改良剂联合施肥引起的微生物变化的理解。
