Microplastics are increasingly recognized as a factor of global change. By altering soil inherentproperties and processes, ripple-on effects on plants and their symbionts can be expected.Additionally, interactions wit...Microplastics are increasingly recognized as a factor of global change. By altering soil inherentproperties and processes, ripple-on effects on plants and their symbionts can be expected.Additionally, interactions with other factors of global change, such as drought, can influence theeffect of microplastics. We designed a greenhouse study to examine effects of polyester microfibers,arbuscular mycorrhizal (AM) fungi and drought on plant, microbial and soil responses. We found thatpolyester microfibers increased the aboveground biomass of Allium cepa under well-watered anddrought conditions, but under drought conditions the AM fungal-only treatment reached the highestbiomass. Colonization with AM fungi increased under microfiber contamination, however, plantbiomass did not increase when both AM fungi and fibers were present. The mean weight diameter ofsoil aggregates increased with AM fungal inoculation overall but decreased when the system wascontaminated with microfibers or drought stressed. Our study adds additional support to themounting evidence that microplastic fibers in soil can affect the plant–soil system by promoting plantgrowth, and favoring key root symbionts, AM fungi. Although soil aggregation is usually positivelyinfluenced by plant roots and AM fungi, and microplastic promotes both, our results show that plasticstill had a negative effect on soil aggregates. Even though there are concerns that microplastic mightinteract with other factors of global change, our study revealed no such effect for drought.展开更多
文摘Microplastics are increasingly recognized as a factor of global change. By altering soil inherentproperties and processes, ripple-on effects on plants and their symbionts can be expected.Additionally, interactions with other factors of global change, such as drought, can influence theeffect of microplastics. We designed a greenhouse study to examine effects of polyester microfibers,arbuscular mycorrhizal (AM) fungi and drought on plant, microbial and soil responses. We found thatpolyester microfibers increased the aboveground biomass of Allium cepa under well-watered anddrought conditions, but under drought conditions the AM fungal-only treatment reached the highestbiomass. Colonization with AM fungi increased under microfiber contamination, however, plantbiomass did not increase when both AM fungi and fibers were present. The mean weight diameter ofsoil aggregates increased with AM fungal inoculation overall but decreased when the system wascontaminated with microfibers or drought stressed. Our study adds additional support to themounting evidence that microplastic fibers in soil can affect the plant–soil system by promoting plantgrowth, and favoring key root symbionts, AM fungi. Although soil aggregation is usually positivelyinfluenced by plant roots and AM fungi, and microplastic promotes both, our results show that plasticstill had a negative effect on soil aggregates. Even though there are concerns that microplastic mightinteract with other factors of global change, our study revealed no such effect for drought.
