典型热带区域农用地微塑料残留特征及种植类型影响  

Microplastics residual and the influence of cultivation type in a typical tropical region

作　　者：钱益斌[1] 何小康 杨帅 严佩 孙宇 陈曦 冯成洪[2,3] QIAN Yibin;HE Xiaokang;YANG Shuai;YAN Pei;SUN Yu;CHEN Xi;FENG Chenghong(Hainan Research Academy of Environmental Sciences,Haikou 571126,China;State Key Laboratory of Water Environment Simulation,Beijing Normal University,Beijing 100875,China;School of Environment,Beijing Normal University,Beijing 100875,China)

机构地区：[1]海南省环境科学研究院,海口571126 [2]北京师范大学水环境模拟国家重点实验室,北京100875 [3]北京师范大学环境学院,北京100875

出　　处：《安全与环境学报》2024年第11期4475-4483,共9页Journal of Safety and Environment

摘　　要：海南岛作为我国主要的热带作物生产基地,独特的气候条件有利于微塑料的形成与残留,系统阐释这一热带典型区域农用地土壤微塑料的残留特征,可以为热带地区塑料污染治理提供重要支撑。研究以海口市琼山区为典型研究区域采集农用地土壤样品,通过密度分离、消解和显微镜观测等步骤提取和鉴定农用地土壤中微塑料的丰度、形状、粒径和颜色等残留特征,探究了微塑料的潜在来源以及人类活动强度对农用地土壤微塑料丰度的影响,并揭示了不同种植类型土壤微塑料分布的差异。结果显示,所有土壤样品均被检测到微塑料,平均丰度为(1023.6±925.5)个/kg,且在空间上呈现东高西低的分布趋势。纤维状(54.6%)、小于0.5 mm(46.0%)以及黑色(49.8%)是该地区农用地微塑料最常见的赋存形态类型。农用地周围人类活动是土壤微塑料污染的重要来源,不同类型农用地中微塑料丰度和形态具有显著性差异,农用塑料地膜的使用是土壤微塑料的直接来源;林地中较低的农业活动强度使得其土壤微塑料丰度较低,破碎程度较少;水田中的上覆水降低了其土壤中微塑料的丰度。This study aims to clarify the impact of different cultivation types and human activity intensity on the characteristics of microplastics in agricultural land soil,promoting plastic pollution control.Through density separation,digestion,and observation,this study extracted and identified the abundance,shape,size,and color of microplastics in agricultural soil.The potential sources of microplastics and the impact of human activity intensity on microplastic abundance were investigated by regression analysis between the night light intensity index and microplastic abundance in soil.The differences in microplastic abundance and morphology characteristics among different types of cultivated soils were revealed with differential tests.The results indicate that microplastics were observed in all the soil samples,with an average abundance of(1023.6±925.5)items/kg.Spatially,microplastic abundance is higher in the east region than that in the west region.The highest abundance was observed in the northeastern region near Meilan International Airport.Furthermore,the significant positive correlation between microplastic abundance and nocturnal light intensity index suggests that human activities surrounding agricultural land are an important source of soil microplastic pollution.Fiber-shaped(54.6%),smaller than 0.5 mm(46.0%),and black(49.8%)are the most common forms of microplastics in the study region.The farmland soil microplastics exhibit a relatively high degree of fragmentation,with a low proportion of colored microplastics,suggesting the potential risk of pigments and other plastic additives release.Significant differences exist in both the abundance and morphology of microplastics among different types of agricultural land.The use of agricultural plastic film directly contributes to soil microplastics.The lower agricultural activity intensity in forest land results in lower soil microplastic abundance and less fragmentation.The overlay water in paddy fields reduces the abundance of microplastics in soil.

关 键 词：环境学 微塑料 农用地 种植类型 人类活动强度 

分 类 号：X53[环境科学与工程—环境工程]