Zhu Yongqi, An Mengjie, Anwar Tumur, Wang Haijiang
Key Laboratory of Biological Resources and Genetic Engineering of Xinjiang Uygur Autonomous Region, College of Life Science and Technology, Xinjiang University, Ürümqi, Xinjiang, China.
Agricultural College, Shihezi University, Shihezi, Xinjiang, China.
Front Microbiol. 2024 Feb 9;15:1288526. doi: 10.3389/fmicb.2024.1288526. eCollection 2024.
Heavy metal pollution is a major worldwide environmental problem. Many remediation techniques have been developed, these techniques have different performance in different environments.
In this study, soil sampling was conducted in multiple cotton fields in Xinjiang, China, and found that cadmium (Cd) was the most abundant soil heavy metal. Then, to find the most suitable technique for the remediation of Cd pollution in cotton fields, a two-year study was conducted to explore the effects of cotton straw-derived biochar (BC, 3%) and -based biofertilizer (BF, 1.5%) on cotton Cd uptake and transport and soil microbial community structure under Cd exposure conditions (soil Cd contents: 1, 2, and 4 mg·kg).
The results showed that the bioaccumulation coefficients (Cd content of cotton organs / soil available Cd content) of cotton roots, stems, leaves, and buds/bolls reduced by 15.93%, 14.41%, 23.53%, and 20.68%, respectively after the application of BC, and reduced by 16.83%, 17.15%, 22.21%, and 26.25%, respectively after the application of BF, compared with the control (no BC and BF). Besides, the application of BC and BF reduced the transport of Cd from soil to root system, and enhanced the diversity of soil bacterial communities (dominant species: and ) and the metabolic functions related to amino acid synthesis. It was worth noting that the differential species for BF group BC group including , , , and were associated with the enrichment and transport of Cd, especially the transport of Cd from cotton roots to stems.
Therefore, the application of BC and BF changed the soil bacterial diversity in Cd-polluted cotton field, and then promoted the transport of Cd in cotton, ultimately improving soil quality. This study will provide a reference for the selection of soil heavy metal pollution remediation techniques in Xinjiang, China.
重金属污染是一个全球性的主要环境问题。人们已经开发了许多修复技术，这些技术在不同环境中的表现各不相同。
本研究在中国新疆的多个棉田进行土壤采样，发现镉（Cd）是土壤中含量最高的重金属。然后，为了找到最适合修复棉田镉污染的技术，进行了一项为期两年的研究，以探讨棉秆生物炭（BC，3%）和生物炭基生物肥料（BF，1.5%）对镉暴露条件下（土壤镉含量：1、2和4 mg·kg）棉花镉吸收和转运以及土壤微生物群落结构的影响。
结果表明，与对照（不施用BC和BF）相比，施用BC后，棉花根、茎、叶和蕾/铃的生物富集系数（棉花器官镉含量/土壤有效镉含量）分别降低了15.93%、14.41%、23.53%和20.68%，施用BF后分别降低了16.83%、17.15%、22.21%和26.25%。此外，BC和BF的施用减少了镉从土壤向根系的转运，并增强了土壤细菌群落的多样性（优势物种： 和 ）以及与氨基酸合成相关的代谢功能。值得注意的是，BF组与BC组的差异物种包括 、 、 和 ，它们与镉的富集和转运有关，特别是镉从棉花根向茎的转运。
因此，BC和BF的施用改变了镉污染棉田的土壤细菌多样性，进而促进了棉花中镉的转运，最终改善了土壤质量。本研究将为中国新疆土壤重金属污染修复技术的选择提供参考。
