Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China.
Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
Sci Total Environ. 2022 Feb 10;807(Pt 3):150982. doi: 10.1016/j.scitotenv.2021.150982. Epub 2021 Oct 14.
Although microplastics have been investigated in terrestrial environments, the occurrence and transport of microplastics in semiarid regions with serious wind erosion are still limited. We investigated plastic debris, including macroplastics (>5 mm) and microplastics (50 μm to 5 mm), from twenty semiarid farmlands and then developed a mass flux model to calculate the quantities of plastic debris transport by wind erosion. Finally, the spatial extent of microplastic deposition was estimated. The average abundance of macroplastics increased with duration of mulching film use, whereas the abundance of microplastics did not change significantly (p > 0.05). Moreover, the highest abundance of microplastics among samples was from the farmland using greenhouse, which suggests that wind erosion played an essential role in retention of plastic debris. Besides, the enrichment ratio (ER) which depends on the shape of microplastics is identified to be a key indicator of the mass flux model. The results showed that 6.91-38.11 kg/ha of plastic debris was released by wind in the 25th year after film application, with 6.14 n/m of microplastics settling in February in Xi'an, which is 690 km away from the source.
虽然已经对陆地环境中的微塑料进行了研究，但在风蚀严重的半干旱地区，微塑料的存在和迁移仍知之甚少。我们调查了来自 20 个半干旱农田的塑料碎片，包括大块塑料（>5 毫米）和微塑料（50 微米至 5 毫米），并开发了一个质量通量模型来计算风蚀作用下塑料碎片的迁移量。最后，估计了微塑料沉积的空间范围。大块塑料的平均丰度随覆盖膜使用时间的延长而增加，而微塑料的丰度没有明显变化（p > 0.05）。此外，温室农田样本中微塑料的丰度最高，这表明风蚀在塑料碎片的保留中起着重要作用。此外，取决于微塑料形状的富集比（ER）被确定为质量通量模型的关键指标。结果表明，在覆膜应用后的第 25 年，有 6.91-38.11 千克/公顷的塑料碎片通过风释放出来，在西安 2 月有 6.14 纳米/米的微塑料沉降，距离源地 690 公里。
