TY - JOUR

T1 - Earthworms alleviate microplastics stress on soil microbial and protist communities

AU - Lu, Siyuan

AU - Wei, Shitong

AU - Li, Meiyan

AU - Chadwick, David R

AU - Xie, Mengmeng

AU - Wu, Donghui

AU - Jones, Davey L

N1 - Copyright © 2024 Elsevier B.V. All rights reserved.

PY - 2024/10/20

Y1 - 2024/10/20

N2 - Microplastic (MP) pollution can exert significant pressure on soil ecosystems, however, the interactive effects of MPs on soil bacterial, fungal and protist communities remains poorly understood. Soil macrofauna, such as earthworms, can be directly affected by MPs, potentially leading to a range of feedbacks on the soil microbial community. To address this, we conducted a microcosm experiment to examine the effects of conventional (i.e., polyethylene, polystyrene) and biodegradable MPs (i.e. PBAT, polylactic acid) on the structure of the soil bacterial, fungal, and protist communities in the presence or absence of earthworms. We found that MP contamination negatively affected the diversity and composition of soil microbial and protist communities, with smaller-sized conventional MPs having the most pronounced effects. For example, compared with the unamended control, small-sized polyethylene MPs both significantly reduced the Shannon diversity of soil bacteria, fungi, and protist by 4.3 %, 37.0 %, and 9.1 %, respectively. Biodegradable MPs increased negative correlations among bacteria, fungi, and protists. However, earthworms mitigated these effects, enhancing the diversity and altering the composition of these communities. They also increased the niche width and stability of the soil microbial food web network. Our study indicated that earthworms help attenuate the response of soil microorganisms to MPs stress by influencing the diversity and composition of soil microorganisms and soil physicochemical properties and underscores the importance of considering macrofauna in MPs research.

AB - Microplastic (MP) pollution can exert significant pressure on soil ecosystems, however, the interactive effects of MPs on soil bacterial, fungal and protist communities remains poorly understood. Soil macrofauna, such as earthworms, can be directly affected by MPs, potentially leading to a range of feedbacks on the soil microbial community. To address this, we conducted a microcosm experiment to examine the effects of conventional (i.e., polyethylene, polystyrene) and biodegradable MPs (i.e. PBAT, polylactic acid) on the structure of the soil bacterial, fungal, and protist communities in the presence or absence of earthworms. We found that MP contamination negatively affected the diversity and composition of soil microbial and protist communities, with smaller-sized conventional MPs having the most pronounced effects. For example, compared with the unamended control, small-sized polyethylene MPs both significantly reduced the Shannon diversity of soil bacteria, fungi, and protist by 4.3 %, 37.0 %, and 9.1 %, respectively. Biodegradable MPs increased negative correlations among bacteria, fungi, and protists. However, earthworms mitigated these effects, enhancing the diversity and altering the composition of these communities. They also increased the niche width and stability of the soil microbial food web network. Our study indicated that earthworms help attenuate the response of soil microorganisms to MPs stress by influencing the diversity and composition of soil microorganisms and soil physicochemical properties and underscores the importance of considering macrofauna in MPs research.

KW - Oligochaeta/physiology

KW - Soil Microbiology

KW - Soil Pollutants

KW - Microplastics

KW - Animals

KW - Microbiota/drug effects

KW - Fungi

KW - Soil/chemistry

KW - Bacteria/drug effects

KW - Ecosystem

KW - Eukaryota/drug effects

U2 - 10.1016/j.scitotenv.2024.174945

DO - 10.1016/j.scitotenv.2024.174945

M3 - Article

C2 - 39043297

VL - 948

SP - 174945

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

ER -