微生物复合菌剂在西北典型煤矿破损生态区修复中的应用

Application of a composite microbial agent in the restoration of ecologically damaged areas in typical coal mines in Northwest China

摘要:

【背景】 煤炭作为重要的能源物质，在生产活动中需求量巨大，但长期的煤炭开采会对矿区生态环境带来极大破坏。微生物修复作为一种对环境友好、操作简单、经济成本低的修复方式，在煤矿区生态系统恢复中有广泛的应用前景。【目的】 利用微生物复合菌剂对煤矿区排土场地进行修复。通过微生物的代谢活动以及与植物根系的相互作用，实现修复煤矿破碎生态环境的目的。【方法】 借助16S rRNA基因高通量测序技术对修复场地微生物群落结构进行分析。通过监测试验场地土壤营养成分、重金属含量以及场地荞麦植株生长状况，评价了微生物修复效果，并初步探究了微生物所发挥的功能。【结果】 试验场地中存在有多种具有修复能力的菌种，微生物菌剂的加入降低了试验场地微生物多样性，但对土著微生物群落结构的影响较小。经过150 d的现场修复，场地有机质含量提高70%、总氮含量提升20%、总钾含量提升48.4%。速效氮、磷、钾也分别提升40%、26.8%和24.2%，土壤肥力得到显著恢复。场地有机质、速效磷和速效钾含量在修复期内呈现出增长趋势，表明功能微生物持续为植物生长提供高效的营养物质。场地砷含量降低49%，铜含量降低41%，表明微生物对场地(类)重金属起到了修复作用。微生物通过促进植株根系生长，提高了植株对营养物质的吸收和利用，场地荞麦株高提高30%，干重提升100%，粗蛋白含量提高22.4%。【结论】 微生物菌剂显著提高了试验场地的土壤肥力，抑制了土壤重金属毒害作用，并有效地促进了场地经济作物的生长。微生物修复在煤矿区破损生态系统的恢复上具有巨大的应用价值。

Abstract:

[Background] As an important energy resource, coal is in high demand in production activities. However, long-term coal mining causes serious damage to the eco-environment. Microbial remediation, as an environmentally friendly, simple, and low-cost remediation method, has broad application prospects in the restoration of coal mining areas. [Objective] We used a composite microbial agent for the remediation of spoil sites in coal mining areas, aiming to restore the fragmented eco-environment of coal mines through microbial activities and interactions of microorganisms with plant roots. [Methods] Utilizing 16S rRNA gene high-throughput sequencing, we analyzed the microbial community structure at the remediation site. By monitoring the soil nutrient content, heavy metal concentrations, and growth of buckwheat plants, we assessed the efficacy of microbial remediation and explored the functions of the microorganisms. [Results] There were diverse microbial species with remediation capabilities at the experimental area. The addition of the microbial agent reduced the microbial diversity but had a minor impact on the indigenous microbial community structure at the experimental site. The on-site restoration for 150 days increased the organic matter, total nitrogen, total potassium, available nitrogen, available phosphorus, and available potassium by 70%, 20%, 48.4%, 40%, 26.8%, and 24.2%, respectively, which indicated the significant recovery in soil fertility. The organic matter, available phosphorus, and available potassium showed an increasing trend during the restoration period, indicating that functional microorganisms continuously provided efficient nutrients for plant growth. The decrease of 49% in arsenic and 41% in copper indicated that microorganisms played a role in the remediation of heavy metals at the site. Microorganisms promoted the growth of plant roots, enhancing the absorption and utilization of nutrients by plants. They increased the buckwheat plant height, dry weight, and crude protein content by 30%, 100%, and 22.4%, respectively. [Conclusion] The microbial agent significantly improved the soil fertility, suppressed the toxic effects of heavy metals in the soil, and promoted the growth of economic crops at the experimental site. Microbial remediation holds a great application value in the restoration of fragmented ecosystems in coal mining areas.