低分子有机酸强化植物修复重金属污染土壤的作用与机制

Role and Mechanism of Low Molecular-Weight-Organic Acids in Enhanced Phytoremediation of Heavy Metal Contaminated Soil

植物修复是利用植物的物理、化学作用去除污染土壤中重金属的技术方法,可以减少二次污染物的产生,具有经济可行性.低分子有机酸(LMWOAs)具有生物降解性和环境友好性,在重金属污染土壤植物修复中具有较强的应用潜力.综述了LMWOAs在植物修复中的作用机制,主要包括:(1)调控根茎叶发育,增加植物生物量,强化植物富集效果;(2)增强光合作用,提升植物抗性,提高对重金属的耐受能力;(3)改变根际土壤性质,提高根际微生物活性,促进对重金属的吸收;(4)改变重金属形态,减轻重金属毒性,提高转运效率.最后阐述了LMWOAs强化植物修复重金属污染土壤的优缺点及应用,提出了LMWOAs在重金属污染土壤植物修复中的研究方向,这对LMWOAs在未来植物修复中的研究和应用具有科学意义.

Phytoremediation is an environmentally friendly technology to remove heavy metals from polluted soil by using the physical and chemical roles of plants. This can effectively reduce the production of secondary pollutants and is economically feasible. Low molecular-weight-organic acids(LMWOAs) are biodegradable and environmentally friendly and have strong application potential in the phytoremediation of heavy metal-contaminated soils. The role and mechanism of LMWOAs in phytoremediation was elaborated on in this study with the aim to:(1) regulate the development of roots, stems, and leaves;increase plant biomass;and enhance plant enrichment of heavy metals;(2) improve photosynthesis, enhance plant resistance, and promote tolerance to heavy metals;(3) change the properties of rhizosphere soil, improve rhizosphere microbial activity, and promote the absorption of heavy metals;and(4) change the form of heavy metals, reduce the toxicity of heavy metals, and improve transport efficiency. Moreover, the advantages, disadvantages, and application of LMWOAs in enhanced phytoremediation of heavy metal-contaminated soil were explored in this study. Finally, the research direction of LMWOAs in the phytoremediation of heavy metal-contaminated soils was proposed, which will have practical scientific significance for the research and application of LMWOAs in future phytoremediation.