Effects of different sizes of microplastic particles on soil respiration, enzyme activities, microbial communities, and seed germination

Bo Gao; Fuyun Gao; Xingfeng Zhang; Yaying Li; Huaiying Yao

doi:10.1016/j.scitotenv.2024.173100

Effects of different sizes of microplastic particles on soil respiration, enzyme activities, microbial communities, and seed germination

Sci Total Environ. 2024 May 11:933:173100. doi: 10.1016/j.scitotenv.2024.173100. Online ahead of print.

Authors

Bo Gao¹, Fuyun Gao², Xingfeng Zhang³, Yaying Li⁴, Huaiying Yao⁵

Affiliations

¹ Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, People's Republic of China; College of Tourism & Landscape Architecture, Guilin University of Technology, Guilin 541004, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo 315830, People's Republic of China.
² Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo 315830, People's Republic of China.
³ College of Tourism & Landscape Architecture, Guilin University of Technology, Guilin 541004, People's Republic of China.
⁴ Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, People's Republic of China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo 315830, People's Republic of China.
⁵ Research Center for Environmental Ecology and Engineering, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, 206 Guanggu 1st road, Wuhan 430205, People's Republic of China. Electronic address: hyyao@iue.ac.cn.

PMID: 38735330
DOI: 10.1016/j.scitotenv.2024.173100

Abstract

Microplastics (MPs) are emerging pollutants of terrestrial ecosystems. The impacts of MP particle size on terrestrial systems remain unclear. The current study aimed to investigate the effects of six particle sizes (i.e., 4500, 1500, 500, 50, 5, and 0.5 μm) of polyethylene (PE) and polyvinyl chloride (PVC) on soil respiration, enzyme activity, bacteria, fungi, protists, and seed germination. MPs significantly promoted soil respiration, and the stimulating effects of PE were the strongest for medium and small-sized (0.5-1500 μm) particles, while those of PVC were the strongest for small particle sizes (0.5-50 μm). Large-sized (4500 μm) PE and all sizes of PVC significantly improved soil urease activity, while medium-sized (1500 μm) PVC significantly improved soil invertase activity. MPs altered the soil microbial community diversity, and the effects were especially pronounced for medium and small-sized (0.5-1500 μm) particles of PE and PVC on bacteria and fungi and small-sized (0.5 μm) particles of PE on protists. The impacts of MPs on bacteria and fungi were greater than on protists. The seed germination rate of Brassica chinensis decreased gradually with the decrease in PE MPs particle size. Therefore, to reduce the impact of MPs on soil ecosystems, effective measures should be taken to avoid the transformation of MPs into smaller particles in soil environmental management.

Keywords: Enzyme activities; Microbial communities; Microplastic particles; Seed germination; Soil respiration.