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Meta Analysis ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 1 ? Systematic review or meta-analysis. Synthesizes findings across many studies. Strongest evidence. Environmental Sources Sign in to save

Microplastics mineralization accelerates soil organic carbon decomposition by positive priming effects: A meta-analysis

Soil Ecology Letters 2025 1 citation ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Shuotian Lai, Changlin Xu, Wei‐Min Wu, Xudong Wang, Yongxiang Yu, Biao Zhu

Summary

A meta-analysis of studies found that microplastics in soil mineralize at 0.114% per day and simultaneously trigger a 33.6% acceleration in soil organic carbon decomposition through positive priming effects driven by microbial co-metabolism and nitrogen mining. This finding reveals that widespread microplastic contamination is actively disrupting terrestrial carbon cycles, with significant implications for climate feedback loops and long-term soil health.

Polymers
Study Type Review

Microplastics (MPs), as a novel global pollutant, are abundant in agricultural soils due to their recalcitrant nature. However, the key drivers regulating MPs mineralization and their impact on soil organic carbon (SOC) decomposition remain unclear. Here, we conducted a meta-analysis to estimate the mineralization rate of MPs in soil and their priming effect (PE) on SOC decomposition. We found that MPs mineralization rate was 0.114% per day, mainly mediated by MPs characteristics (chemical composition and particle size) and soil pH. MPs input simultaneously induced a significant positive PE, accelerating SOC decomposition by 33.6% on average. This process was primarily regulated by soil carbon (C):nitrogen (N) ratio and pH, and there was a significant correlation between MPs mineralization and PE. Furthermore, dissolved organic C and microbial biomass C and N in soil increased after MPs input, while nitrate decreased. These results indicated that the positive PE induced by MPs may be driven by soil microbial co-metabolism and N mining. Collectively, our findings emphasize the crucial role of MPs in terrestrial biogeochemical cycles and provide an improved assessment of SOC turnover under the global MPs crisis.

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