城市堆肥中的塑料颗粒及其颗粒大小分布
Hana Brťková1, Jana Růžičková1, Karolina Slamová2
1Centre CEET/ENET, VŠB - Technical University of Ostrava, Ostrava-Poruba, Moravian-Silesian Region, 708 00, Czech Republic.
Environmental pollution (Barking, Essex : 1987)
|April 26, 2024
概括
这项研究在城市绿色堆肥中发现了微塑料 (MP) 和添加剂,在特定颗粒大小中度更高. 这些化合物和其他有机物质的可溶性受堆肥的影响.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 聚合物科学 聚合物科学
背景情况:
- 堆肥中的微塑料 (MP) 污染对环境构成风险,并影响土壤特性.
- 了解MP的行为和堆肥中的降解对于可持续的土地应用至关重要.
研究的目的:
- 在城市绿色堆肥中量化微塑料和添加剂.
- 为了研究MP度,颗粒大小和堆肥特性之间的关系.
- 评估堆肥液对植物发芽的影响.
主要方法:
- 用于聚合物和添加剂识别的热解气体染色学和质谱学 (Py-GC/MS).
- 分析不同堆肥颗粒大小分量的微塑料度.
- 确定堆肥的化学性质 (C/N比,溶解的有机碳,水溶性).
- 使用发芽指数 (GI) 测试评估堆肥植物毒性.
主要成果:
- 聚乙烯二甲,聚烯,聚乙烯和聚烯被确定为主要的微塑料.
- 微塑料和添加剂在0.315-0.63毫米和0.63-1.25毫米颗粒大小类中最为集中.
- 在C/N比率和塑料颗粒度之间发现了显著的相关性.
- 与主要聚合物分解产品相比,观察到添加剂的可性更高.
- 最低的发芽指数 (GI) 记录在0.63-1.25毫米分数中,受塑料液和溶解有机碳/水溶性的影响.
结论:
- 城市绿色堆肥含有大量的微塑料和添加剂,特别是在更细的颗粒分数中.
- 在堆肥降解过程中,塑料颗粒的行为与纤维素酸的行为相似.
- 堆肥液,包括添加剂和有机物成分,可以对植物发芽产生负面影响.
- 需要进一步的研究才能充分了解堆肥中微塑料的生态毒理学影响.
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