Effects of microplastics pollution on plant and soil phosphorus: A meta-analysis

The widespread use of microplastics leads to environmental pollution, which threatens ecosystem functions (i.e., nutrient cycling). Some studies have focused on the impacts of microplastics on phosphorus from plants and soils. However, inconsistent responses of plant and soil phosphorus to microplastics have been observed. This work synthesized the results of 781 paired observations from 73 publications to explore the overall effects of microplastics on plant and soil phosphorus and whether the impacts depended on microplastics properties and experimental variables. We found the overall negative effects of microplastics on plant phosphorus and soil available phosphorus. Additionally, microplastics significantly inhibited neutral phosphatase activity but increased soil phosphorus leaching. Furthermore, the impacts of microplastics on plant and soil phosphorus varied depending on microplastics types, sizes, concentrations, and experimental durations. Soil total phosphorus and available phosphorus exhibited stronger negative responses to biodegradable than conventional microplastics. Acid phosphatase was more sensitive to biodegradable than conventional microplastics. In addition, soil total phosphorus, available phosphorus, and alkaline phosphatase were significantly correlated with microplastic concentrations and exposure time. Overall, our findings suggest that microplastics potentially threaten soil fertility and plant productivity. This work provides an important reference for predicting ecosystem functions in the context of microplastics pollution. This study indicates that microplastics pollution reduced plant phosphorus and soil phosphorus, suggesting that the application of microplastics potentially threaten soil fertility and plant productivity. In addition, microplastics type, size, concentration, and exposure time affect the responses of microplastics to plant and soil phosphorus, which contributes to a comprehensive understanding on the potential mechanisms of effects of microplastics addition on phosphorus components. It provides an important reference for predicting ecosystem functions in the context of microplastics pollution. [Display omitted] •Microplastics pollution had negative effects on plant soil phosphorus.•Effects of microplastics on plant and soil phosphorus varied depending on microplastics properties and experimental conditions.•Microplastics potentially threaten soil fertility and plant productivity, especially in regions of inten