Responses of Rhizosphere Soil Physicochemical Properties and Enzyme Activities to Polyethylene Microplastic Stress in Maize–Soybean Intercropping
Year: 2026
Type: article
Abstract: Agricultural microplastics threaten soil health, yet rhizosphere microecological responses to microplastic stress in intercropping systems remain unclear. We conducted a pot experiment using two cropping systems (maize monocropping and maize–soybean intercropping) and four polyethylene microplastic (PE-MP) levels (0%, 0.1%, 0.5%, 1.0%) to investigate rhizosphere physicochemical properties and enzyme activities. Results showed a significant interaction between PE-MPs and cropping systems (p < 0.05). In MM, 0.1% PE-MPs exacerbated soil acidification (pH −4.32%) and ionic fluctuations (electrical conductivity +11.12%). At ≥0.5%, PE-MPs significantly decreased total nitrogen (TN) and total phosphorus, induced abnormal available phosphorus accumulation (up to +98.4%), and dose-dependently inhibited β-glucosidase, urease, and catalase activities. Conversely, the IM system exhibited buffering capacity, maintaining pH, electrical conductivity, and TN stability, mitigating nutrient imbalances, and preserving key enzyme functions. PLS-SEM revealed enzyme-specific associations, suggesting that cropping systems and PE-MPs drive enzyme activities primarily by regulating TN and dissolved organic carbon (DOC). Conclusively, maize–soybean intercropping can buffer microplastic-induced physicochemical degradations, indicating its potential as an agronomic measure to mitigate microplastic pollution, though field-scale validations remain necessary.
Source: Agriculture
Authors: Debin Sun, Zhangyong Li, Yuanlan Lei, Yan Qiu, Jingxiu Xiao, Yi Zheng
Institutions: Yunnan Agricultural University, Yunnan Open University
Language: English
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
SDGs: Zero hunger, Life on land
Open Access status: gold
Estimated APC paid: $3,137
Awards: G1038757193, G115852486, G2215950553
OpenAlex ID: W7204437773