次生微塑料食物暴露对土壤白符跳Folsomia Candida毒性的初步研究

TOXICITY OF SUBMICROPLASTIC ON SOIL COLLEMBOLANS FOLSOMIA CANDIDA BY FOOD EXPOSURE

土壤微塑料污染已引起国内外学者的广泛关注。但关于次生微塑料在土壤动物食物链上的迁移及其毒理效应的研究较少。为探究次生微塑料的生物传递效应,本试验以同步化14 d(幼虫)和28 d(成虫)的土壤白符跳(Folsomia Candida)为供试生物,将废料(塑料类废料混合物)、保温棉、麦麸保温棉混合和细保温棉经黄粉虫(Tenebrio molitor Linnaeus)降解后形成的4种不同次生微塑料产物作为处理因子,研究次生微塑料对土壤跳虫生物学的影响。结果发现:1)第7天,所有跳虫开始蜕皮,喂食保温棉、麦麸保温棉和细保温棉组的幼虫死亡率分别为1.67%、1.67%和5%;2)第14天,跳虫蜕皮量增多,保温棉和细保温棉组的幼虫死亡率分别为6.67%和5%,各组成虫产卵量剧增,喂食酵母菌的对照组产卵率显著高于处理组;3)第28天,蜕皮量增势趋缓,除废料组外,各组幼虫开始产卵且无死亡现象发生;4)与处理组相比,对照组中跳虫的蜕皮量、产卵量和生物量都是最高的,且体长变化显著(P<0.05)。综上,研究结果将进一步完善次生微塑料对土壤动物毒理效应的基础数据,为土壤环境中的次生微塑料的生态风险评价提供理论依据。

Microplastics had serious impact on soil ecosystem with the increasing concern. However,few studies on the migration of microplastics in the food chain of soil animals and their toxicological effects were available. In order to explore the biological transfer effect of sub-microplastics,four different materials,components of waste,heat preservation cotton,wheat bran-thermal insulation cotton and fine insulation cotton treated by Folsomia Candida,were used as a treatment factor to study the physiological and ecological effects of sub-microplastics on soil collembolans. The results showed that: 1) on the 7 th day,all the collembolans began to molt,and the larval mortality rates of the groups fed with heat preservation cotton,wheat bran heat preservation cotton and fine heat preservation cotton were 1. 67%,1. 67% and 5%,respectively;2) on the 14 th day,the amount of molting increased,and the mortality of larvae in the groups of heat preservation cotton and fine heat preservation cotton was 6. 67% and 5%,respectively,the oviposition of adults in each group increased sharply,and the oviposition rate of the control group fed with yeast was significantly higher than that of the treatment group;3) on the 28 th day,the increase of molting amount slowed down,except for the waste group,the larvae of each group increased;4) compared with the control group,the molting,oviposition and biomass of the control group were the highest,and the body length increased significantly( P<0. 05). The results of this study would further improve the basic data of the toxicological effects of sub-microplastics on soil animals,and provide theoretical basis for ecological risk assessment of sub-microplastics in soil environment.