Maqbool Ahsan, Guzmán Gema, Fiener Peter, Wilken Florian, Soriano María-Auxiliadora, Gómez José A
Institute for Sustainable Agriculture, CSIC, Cordoba 14004, Spain; Doctorate Program "Ingeniería Agraria, Alimentaria, de los Recursos Naturales y del Desarrollo Rural Sostenible" University of Córdoba, 14014 Córdoba, Spain.
IFAPA-Camino de Purchil, Granada 18004, Spain.
J Hazard Mater. 2024 Sep 15;477:135318. doi: 10.1016/j.jhazmat.2024.135318. Epub 2024 Jul 25.
Soil is polluted with plastic waste from macro to submicron level. Our understanding of macroplastics (> 5 mm) occurrence and behavior has remained comparatively elusive, mainly due to a lack of a tracing mechanism. This study set up a methodology to trace macroplastic displacement, which combined magnetic iron oxide-tagged soil and macroplastic pieces tagged by an adhesive passive radiofrequency identification transponder. By utilizing these techniques, a field study was carried out to analyze the effect of tillage implement and plastic sizes on plastic displacement, to understand the fate of macroplastics in arable land. Results indicated that the displacement of macroplastics did not depend upon plastic sizes but did depend upon the tillage implement used. The mean macroplastics displacement per tillage pass was 0.36 ± 0.25 m with non-inversion chisel tillage and 0.15 ± 0.13 m with inversion disk tillage, which was similar to bulk soil displacement. However, only inversion disk tillage caused fragmentation (41 %) of macroplastics and generated microplastics (< 5 mm). In contrast, both tillage implements drove to similar burial of surface macroplastics into the tilled layer (74 % on average). These results highlight that tillage is a major process for macroplastics fate in arable soils, being one of the first studies to investigate it.
土壤从宏观到亚微米级都受到塑料垃圾的污染。我们对宏观塑料（>5毫米）的出现和行为的理解相对仍然难以捉摸，主要是由于缺乏追踪机制。本研究建立了一种追踪宏观塑料位移的方法，该方法将磁性氧化铁标记的土壤和由粘性无源射频识别应答器标记的宏观塑料片相结合。通过运用这些技术，开展了一项田间研究，以分析耕作工具和塑料尺寸对塑料位移的影响，从而了解耕地中宏观塑料的归宿。结果表明，宏观塑料的位移不取决于塑料尺寸，而是取决于所使用的耕作工具。每次耕作时，非翻转凿式耕作的宏观塑料平均位移为0.36±0.25米，翻转圆盘耕作的为0.15±0.13米，这与土壤整体位移相似。然而，只有翻转圆盘耕作导致宏观塑料破碎（41%）并产生微塑料（<5毫米）。相比之下，两种耕作工具都使地表宏观塑料平均有相似程度（平均74%）地埋入耕作层。这些结果凸显出耕作是耕地土壤中宏观塑料归宿的一个主要过程，这是首批对此进行研究的工作之一。
