Microplastics threaten agroecosystem multifunctionality: A global systematic review with national-scale evidence from China.

Microplastics are an emerging group of pollutants accumulating in global croplands; yet, while recent syntheses have quantified the global average magnitude of microplastic impacts, their potential spatial manifestation and regional risk patterns across large-scale agrarian systems remain poorly understood. Here, this study combines a mechanistic review with quantitative synthesis and scenario-based spatial modelling to translate global terrestrial microplastic effect-size evidence into 5-km potential risk maps for China's croplands. Under a widespread microplastic contamination scenario, the largest predicted loss occurred in plant productivity (-24.02%), followed by soil enzyme activity (-9.50%), soil fertility (-8.92%), microbial biomass (-6.28%), and microbial diversity (-3.68%), whereas apparent soil carbon accumulation increased (+6.98%). Spatially, multifunctional degradation was concentrated mainly in Northeast China, the North China Plain, and the middle-lower Yangtze River Plain. Random Forest importance analysis, variance partitioning analysis, and partial least squares path modelling indicated that soil texture, climatic water stress, and terrain jointly regulated spatial differences in ecosystem-service sensitivity. This study provides one of the first national-scale spatializations of global terrestrial microplastic effect-size evidence and identifies scenario-based priority regions for differentiated monitoring, field validation, and mitigation.