生态与农村环境学报 ›› 2023, Vol. 39 ›› Issue (5): 617-624.doi: 10.19741/j.issn.1673-4831.2023.0167

• 微/纳塑料生物生态和环境效应 • 上一篇    下一篇

生物炭对设施土壤中聚氯乙烯微塑料植物毒性的影响研究

李嘉, 喻雨霏, 崔敏   

  1. 扬州大学环境科学与工程学院, 江苏 扬州 225127
  • 收稿日期:2023-03-08 出版日期:2023-05-25 发布日期:2023-05-24
  • 通讯作者: 李嘉,E-mail:lijia3611@yzu.edu.cn E-mail:lijia3611@yzu.edu.cn
  • 作者简介:李嘉(1990-),男,山东烟台人,副教授,博士,主要研究方向为新污染物迁移转化。E-mail:lijia3611@yzu.edu.cn
  • 基金资助:
    国家自然科学基金(42007108)

Effects of Biochar on the Phytotoxicity of Polyvinyl Chloride Microplastics in Greenhouse Soil

LI Jia, YU Yu-fei, CUI Min   

  1. College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225127, China
  • Received:2023-03-08 Online:2023-05-25 Published:2023-05-24

摘要: 聚氯乙烯(polyvinyl chloride, PVC)微塑料广泛分布于设施土壤中,具有较强的植物毒性,对农作物生长发育构成严重威胁,因此,亟需采取措施降低土壤微塑料的植物毒性。生物炭具有较强的吸附能力,能有效钝化土壤污染物,被广泛应用于污染土壤修复。此外,生物炭在改土增产方面表现出巨大潜力。为了探究生物炭对土壤中PVC微塑料植物毒性的影响,对比分析了单一PVC微塑料暴露以及PVC微塑料和不同浓度生物炭复合暴露条件下生菜的生长指标和生理生化指标。结果表明,单一PVC微塑料暴露下生菜叶片叶绿素含量较对照组显著增加(P<0.01),然而,生菜地下部和地上部生物量却分别降低23.54%和12.04%。这可能是因为PVC微塑料附着在生菜根系表面,诱导根部过氧化氢(H2O2)积累并产生氧化损伤,从而影响根系的正常生理功能。向PVC微塑料污染土壤中添加质量分数w为0.5%~2.5%的生物炭,降低了生菜根部和叶片丙二醛(MDA)含量,并使得生菜生物量较单一PVC微塑料处理组有所增加。但是,高浓度(w=5.0%)生物炭加剧了生菜根部的氧化损伤,其对生菜的促生长作用也相继减弱。因此,通过添加适量生物炭能够缓解土壤微塑料的植物毒性,这为治理设施土壤微塑料污染提供了科学依据。

关键词: 微塑料, 设施土壤, 生菜, 植物毒性, 氧化应激

Abstract: Polyvinyl chloride (PVC) microplastics are commonly found in greenhouse soils. They are highly phytotoxic and pose a serious threat to plant growth and development. Therefore, measures to reduce the phytotoxicity of PVC microplastics are urgently needed. Biochar is known for its strong adsorption capacity. It can effectively passivate soil contaminants and has been widely used in the remediation of soil contamination. Additionally, biochar has exhibited great application potential for improving soil quality and increasing crop yields. To determine the effect of biochar on PVC microplastic phytotoxicity in greenhouse soils, the growth, physiological and with biochemical indices of lettuce (Lactuca sativa) were analyzed under single exposure to PVC microplastics and combined exposure to PVC microplastics and with biochar at different concentrations. The results show that the chlorophyll content of lettuce leaves exposed to single PVC microplastics was significantly increased compared to the control group (P<0.01). However, the biomass of root and shoot of lettuce was reduced by 23.54% and 12.04%, respectively. This may be attributed to the adhesion of PVC microplastics to the surface of lettuce roots, which induced the production and accumulation of hydrogen peroxide (H2O2) in the roots and caused oxidative damage, thus affecting the normal physiological function of the roots. The addition of 0.5% to 2.5% biochar to the PVC microplastics-contaminated soil resulted in a decrease in malondialdehyde (MDA) levels in lettuce roots and leaves and an increase in lettuce biomass compared to the single PVC microplastics exposure treatment group. However, the high concentration (5.0%) of biochar exacerbated the oxidative damage to lettuce roots and attenuated its growth-promoting effect on lettuce. These results suggest that the phytotoxicity of soil microplastics can be mitigated by the addition of appropriate amounts of biochar, and can provide a scientific basis for addressing soil microplastic pollution in agriculture.

Key words: microplastics, greenhouse soil, lettuce, phytotoxicity, oxidative stress

中图分类号: