设施农业土壤微塑料污染及其对细菌群落多样性的影响  

Microplastics contamination in the protected agricultural soils and its effects on bacterial community diversity

作　　者：费禹凡 黄顺寅 王佳青 骆永明[3] 章海波 Yufan Fei;Shunyin Huang;Jiaqing Wang;Yongming Luo;Haibo Zhang(School of Environment and Resources,Zhejiang Agriculture and Forestry University,Hangzhou 311300,China;Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province,Hangzhou 311300,China;Key Laboratory of Soil Environment and Pollution Remediation,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China)

机构地区：[1]浙江农林大学环境与资源学院,杭州311300 [2]浙江省土壤污染生物修复重点实验室,杭州311300 [3]中国科学院南京土壤研究所中国科学院土壤环境与污染修复重点实验室,南京210008

出　　处：《科学通报》2021年第13期1592-1601,共10页Chinese Science Bulletin

基　　金：国家自然科学基金(41771351,41877142,41991330);浙江省自然科学基金(LZ19D10001);浙江农林大学人才启动项目(2017FR021)资助。

摘　　要：设施农业土壤普遍使用塑料薄膜覆盖和施加大量有机肥,可能成为微塑料污染区.对杭州湾沿岸集中连片设施农业区54个表层土壤样品的调查研究表明,黑色地膜覆盖土壤中微塑料丰度普遍高于透明棚膜、棚膜与地膜结合覆盖土壤,微塑料最高丰度可达1560个/kg,聚乙烯薄膜类微塑料普遍存在.进一步通过聚乙烯微塑料污染土壤暴露培养29 d的试验结果表明,微塑料的添加会一定程度抑制土壤细菌群落丰富度的恢复.16S r RNA高通量测序结果显示,土壤细菌群落结构的改变不随微塑料暴露量的增加而加剧,1%暴露量时聚乙烯微塑料对土壤细菌群落结构的影响比5%暴露量时更为显著;土壤中的微塑料暴露主要使鞘脂单胞菌目(Sphingomonadales)、黄色单胞菌目(Xanthomonadales)、丙酸杆菌目(Propionibacteriales)、Chitinophagales、鞘脂杆菌目(Sphingobacteriales)和黄杆菌目(Flavobacteriales)等相对丰度显著上升,而未分类的放线菌目(unclassified Actinobacteria)、β-变形菌目(Betaproteobacteriales)、粘球菌目(Myxococcales)、芽单胞菌目(Gemmatimonadales)等相对丰度显著下降;KEGG代谢通路预测显示土壤微塑料污染可能会影响异黄酮等次级代谢产物的生物合成,促进多环芳烃的降解.未来需进一步从相关功能基因角度探讨微塑料污染对土壤中养分和外源污染物生物转化的影响.Mircroplastics(MPs)are defined as plastic particles or fibers of size<5 mm and have been of concern in terrestrial ecosystems for several years.Protected agricultural soils have been assumed to be potentially contaminated with MPs because of the use of large amounts of plastic films and annual compost inputs.However,there is little published information on MP contamination of protected agricultural soils and its ecological effects on soil biota remain unknown.Here,a total of 54 surface(0-10 cm depth)soils were sampled from intensively managed protected agricultural soils around Hangzhou Bay,east China.MPs were extracted from the soil samples using continuous air flotation followed by density separation.Stereomicroscopy and micro-Fourier transform infrared spectroscopy(μ-FTIR)were used for identification after the extracted MPs were pre-sorted based on their shapes.In addition,a 29-d soil incubation experiment was conducted to observe the changes in microbial community diversity due to MP contamination.Soils were spiked with1%and 5%(w/w)low density polyethylene(LDPE)MPs(average size 678μm)and sampled at an intervals of 1,15 and29 d in an incubation experiment.The soil bacterial community in these samples was analyzed using high-throughput sequencing technology.A field survey of the protected agricultural soils indicates that soil MP abundance ranged from 20 to 1560 pieces kg-1 with an average of 443 pieces kg^(-1).Fragments dominated the MP types which comprised films,fragments and fibers,likely originating from compost applications to the soils.LDPE MPs occurred mainly in MP films and were widely distributed in soil samples from mulched soils.Soil MP was also influenced by the type of plastic mulching film used.Relatively high MP abundance was found in soils covered with black mulching film compared with other types of film.Soil MP contamination was found to affect soil microorganisms in the incubation experiment.The Chao1 index(which indicates the richness of the bacterial community)decreased initially and the

关 键 词：设施农业土壤 微塑料 积累 微生物群落结构 功能多样性 

分 类 号：X53[环境科学与工程—环境工程] S154.3[农业科学—土壤学]