摘要
微塑料作为一种新兴环境污染物,广泛分布于全球各生态系统中,备受国内外学者的关注。为了解微塑料在挠力河自然保护区分布、组成特征及生态风险,本研究以保护区内旱田地、水田地、林地和沼泽四种类型土地为研究对象,利用改进的浮选分离法对不同样品中微塑料进行分离,使用体式显微镜和傅里叶变换红外光谱仪(μ-FITR)对0.02~5 mm粒径范围的微塑料进行检测,观察并鉴定微塑料形状、颜色,分析其丰度和成分,同时采用风险指数(R)和污染负荷指数(PLI)对微塑料生态风险进行评估。结果表明:(1)微塑料形状有纤维状、碎片状、薄膜状和颗粒状四种,纤维状和薄膜状分别占比31.5%、37.0%,其中薄膜状微塑料在旱田地和沼泽两种类型土地中含量差异显著(P<0.05);微塑料颜色包括白色、黑色、红色、蓝色和透明色五种,各颜色微塑料组分在四种类型土地中差异不显著;微塑料成分包括聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)和聚乙烯(PE)三种,分别占54.5%、27.3%和18.2%,且各组分间无相关性。(2)微塑料丰度范围为3.33~30.0 n·kg^(-1),平均丰度为14.3 n·kg^(-1),且旱田地微塑料平均丰度显著大于林地和沼泽两种类型土地(P<0.05);微塑料平均丰度在空间上呈现旱田地(21.1 n·kg^(-1)>水田地(12.2 n·kg^(-1)>沼泽(10.7 n·kg^(-1)>林地(8.89 n·kg^(-1)的分布趋势。(3)尺寸小于1 mm的微塑料占总检出微塑料的87.7%,且主要集中在0.2~0.5 mm和0.5~1 mm粒径范围内,分别占30.1%和34.2%。(4)保护区四种土地利用类型平均风险指数为3.64,总体污染负荷指数为2.31×10^(-2),分析可得保护区总体生态风险水平较低。数据显示,挠力河自然保护区四种类型土地中均存在不同丰度的微塑料,并且具有独特的赋存形态及分布特征,这为保护区微塑料污染防控和迁移转化研究提供了基础数据支持。
As an emerging environmental pollutant,microplastics are widely distributed around the world and are greatly concerned by scientists.In order to study the distribution,composition characteristics and ecological risk of microplastics in Naolihe Nature Reserve,we selected four typical land use types:upland field,paddy field,forest and swamp in the reserve,and investigated shape,color,abundance and composition of microplastics by using the improved flotation separation method.We also detected the microplastics in the particle size range of 0.02-5 mm,observed and identified relevent index by stereoscopic microscope and Fourier transform infrared spectrometer(μ-FITR).The ecological risk of microplastics was also evaluated based on risk-index(R)and the pollution load index(PLI).The results showed that:(1)The microplastics shape was fibrous,fragmentary,film-like and granular,of which fibrous and film-like accounted for 31.5%and 37.0%,with a significant difference between upland field and swamp soil(P<0.05).The colors of microplastics included white,black,red,blue,and transparent.There was no significant difference in color components among the four land use types.The microplastics composition included polypropylene(PP),polyethylene glycol terephthalate(PET)and polyethylene(PE),accounting for 54.5%,27.3%and 18.2%,respectively.There was no significant regression correlation between the compositions.(2)The abundance of microplastics ranged from 3.33 to 30.0 n·kg^(−1),with an average abundance of 14.3 n·kg^(−1),and the average abundance of microplastics in upland field was significantly higher than that in forest and swamp(P<0.05).Spatially,the distribution trend was in the order of upland field(21.1 n·kg^(−1))>paddy field(12.2 n·kg^(−1))>swamp(10.7 n·kg^(−1))>forest(8.89 n·kg^(−1)).(3)Microplastics with a size of less than 1 mm accounted for 87.7%,mainly in the range of 0.2~0.5 mm and 0.5~1 mm particle size,accounting for 30.1%and 34.2%,respectively.(4)The average risk index of four land use types in the reserve was 3.64,and the overall pollution load index was 2.31×10^(−2).The overall ecological risk level of the reserve was low.These showed that there were different degrees of microplastic pollution in the four land use types in the reserve,with unique occurrence forms and distribution characteristics.The research provides basic support for the pollution prevention and control,migration and transformation of microplastics in the reserve.
作者
教明明
卓依恒
孙泽林
崔兴波
孟昭军
刘曼红
JIAO Mingming;ZHUO Yiheng;SUN Zelin;CUI Xingbo;MENG Zhaojun;LIU Manhong(Northeast Forestry University,Harbin 150040,China;Heilongjiang Naolihe National Nature Reserve Administration,Shuangyashan 155100,China)
出处
《土壤与作物》
2023年第2期141-152,共12页
Soils and Crops
基金
黑龙江省自然科学基金项目(LH2020C088)。
关键词
挠力河自然保护区
微塑料
不同类型土地
丰度
风险评估
Naolihe Nature Reserve
microplastics
different types of land use
abundance
risk assessment