Liang Rong, He Jiao, Sun Fei-Hu, Zhang Rui-Fang, Wang Xin-Xin
College of Resources and Environment Science, Hebei Agricultural University, Baoding 071001, China.
Agricultural Technology Innovation Center in Mountainous Areas of Hebei Province, Baoding 071001, China.
Huan Jing Ke Xue. 2024 Jun 8;45(6):3679-3687. doi: 10.13227/j.hjkx.202306183.
The threat of microplastic pollution in soil ecosystems has caused widespread concern. In order to clarify the effect of polyethylene microplastics on soil properties, a 4-month soil incubation experiment was conducted in this study to investigate the effect of different mass fraction (1 %, 2.5 %, and 5 %) and particle sizes (30 mesh and 100 mesh) of polyethylene microplastics on soil chemical properties, nutrient contents, and enzyme activities. The results showed that:① When the particle size was 100 mesh, microplastics at the mass concentrations of the 2.5 % and 5 % treatments significantly reduced soil pH, and the exposure of polyethylene microplastics had no significant effect on soil conductivity. ② Compared to that in CK, the addition of microplastics reduced soil available potassium, available phosphorus, and nitrate nitrogen to varying degrees. The addition of 100 mesh microplastics significantly increased soil organic matter and ammonium nitrogen. ③ When the particle size was 100 mesh, compared to that in CK, treatments of all concentrations significantly increased soil catalase activity and alkaline phosphatase, showing an increasing but not significant trend, and the 5 % concentration treatment significantly decreased soil sucrase activity. ④ Changes in soil properties were influenced by the addition of microplastics of different concentrations and sizes, with higher concentrations and smaller particle sizes having more significant effects. In conclusion, the effects of microplastics on soil properties were not as pronounced as expected, and future research should focus on the mechanisms involved in the different effects.
土壤生态系统中微塑料污染的威胁已引起广泛关注。为阐明聚乙烯微塑料对土壤性质的影响，本研究进行了为期4个月的土壤培养实验，以探究不同质量分数（1%、2.5%和5%）和粒径（30目和100目）的聚乙烯微塑料对土壤化学性质、养分含量及酶活性的影响。结果表明：①当粒径为100目时，质量浓度为2.5%和5%处理的微塑料显著降低了土壤pH值，而聚乙烯微塑料的添加对土壤电导率无显著影响。②与对照相比，微塑料的添加不同程度地降低了土壤速效钾、速效磷和硝态氮含量。添加100目微塑料显著增加了土壤有机质和铵态氮含量。③当粒径为100目时，与对照相比，各浓度处理均显著提高了土壤过氧化氢酶活性和碱性磷酸酶活性，呈增加但不显著的趋势，5%浓度处理显著降低了土壤蔗糖酶活性。④土壤性质的变化受不同浓度和粒径微塑料添加的影响，浓度越高、粒径越小，影响越显著。总之，微塑料对土壤性质的影响不如预期显著，未来研究应聚焦于不同影响所涉及的机制。
