农艺措施和道路 proximity 驱动农业土壤中的塑料污染：来自印度比哈尔邦关于风化、元素关联和生态风险的见解。注：这里“road proximity”直接保留英文未翻译，因为不清楚其准确含义，可能是“道路临近度”之类的特定术语，需结合更多背景信息准确翻译。

Agronomic practices and road proximity drive plastic pollution in agricultural soils: Insights from Bihar, India on weathering, elemental association, and ecological risk.

作者信息

Karwadiya Jayant, Kerketta Alok Ranjan, Pathak Saurabh Kumar, Srivastava Sudhakar, Darbha Gopala Krishna

机构信息

Environmental Nanoscience Laboratory, Department of Earth Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India, 741246.

Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, Uttar Pradesh, India, 221005.

出版信息

Environ Pollut. 2025 Aug 8;384:126975. doi: 10.1016/j.envpol.2025.126975.

DOI:10.1016/j.envpol.2025.126975

PMID:40784475

Abstract

The widespread use of plastics in agriculture, particularly through mulching and polyhouse practices, has intensified concerns over soil contamination. However, limited research has addressed how spatial factors and agronomic practices, such as proximity to roads and mulching, influence macroplastics (MaP) and microplastics (MP) distribution in agricultural soils, particularly in India. This study assessed plastic contamination across 22 sites in six districts of Bihar, revealing mean MaP concentrations of 7.5 ± 3.6 particles kg soil (d.w.) and MP levels ranging from 150 to 1460 particles kg soil. MP concentrations were highest in mulched fields near roads (803 ± 371 particles kg), followed by distant mulched sites (657 ± 143 particles kg). Elevated levels were observed even in unmulched near-road fields (494 ± 327 particles kg), while the unmulched, distant fields (335 ± 76 particles kg) had the least contamination, indicating a combined influence of agricultural practices and road proximity. Polymer characterization revealed four types of MPs (PP > PE > PET > PS), with PE and PP accounting for over 95 % of the total. Weathering assessment via carbonyl index (CI) showed significantly higher values in MPs than MaPs, and field-extracted mulch films exhibited reduced contact angles relative to pristine films, indicating increased surface oxidation and hydrophilicity. Furthermore, MPs were found to adsorb multiple heavy metals, including Pb, Cu, Cr, Cd, Co, As, and Zn, highlighting risks of co-contaminant transport. Based on the MultiMP framework, all field types were classified as high-risk for MPs related impacts. These findings emphasize the need for sustainable plastic use in agriculture and call for targeted policy measures, including improved disposal practices and adoption of biodegradable alternatives, to mitigate long-term soil degradation and ecological harm.

摘要

塑料在农业中的广泛使用，特别是通过地膜覆盖和温室栽培，加剧了人们对土壤污染的担忧。然而，关于空间因素和农艺措施（如靠近道路和地膜覆盖）如何影响农业土壤中宏观塑料（MaP）和微塑料（MP）分布的研究有限，尤其是在印度。本研究评估了比哈尔邦六个区22个地点的塑料污染情况，结果显示MaP的平均浓度为7.5±3.6颗粒/千克土壤（干重），MP含量在150至1460颗粒/千克土壤之间。道路附近的地膜覆盖田块中MP浓度最高（803±371颗粒/千克），其次是远处的地膜覆盖地点（657±143颗粒/千克）。即使在道路附近未覆盖地膜的田块中也观察到较高水平（494±327颗粒/千克），而未覆盖地膜且距离较远的田块（335±76颗粒/千克）污染最少，这表明农业措施和靠近道路存在综合影响。聚合物表征显示有四种类型的MPs（PP>PE>PET>PS），其中PE和PP占总量的95%以上。通过羰基指数（CI）进行的老化评估表明，MPs中的值明显高于MaPs，并且田间提取的地膜相对于原始薄膜表现出减小的接触角，表明表面氧化和亲水性增加。此外，发现MPs吸附多种重金属，包括Pb、Cu、Cr、Cd、Co、As和Zn，突出了共污染物运输的风险。基于MultiMP框架，所有田块类型在MPs相关影响方面都被归类为高风险。这些发现强调了在农业中可持续使用塑料的必要性，并呼吁采取有针对性的政策措施，包括改进处置方法和采用可生物降解替代品，以减轻长期土壤退化和生态危害。