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One of humanity’s contemporary challenges is continuously satisfying the need for global food and environmental security. Numerous individual reports have emphasized the importance of soil surface plastic mulch (PM) as an auxiliary means of increasing crop yields, but a comprehensive assessment of yields and environmental benefits on a national scale has not been performed. A meta-analysis was conducted to compare PM and no-mulch (NM) cropping patterns in China, the largest plastic film consumer in the world. Overall, PM positively influenced crop yields, particularly in semi-arid regions with medium and high nitrogen (N) input. The mean yield increased by 18% for wheat and 27% for maize; these changes were explained by the capacity of PM to increase water use efficiency (17% for wheat and 30% for maize). Notably, PM always increased greenhouse gas (GHG) emissions, and the mean yield scaled GHG emissions increased by 32% for wheat and 10% for maize on a countrywide scale. In detail, compared to NM, PM resulted in a 2-113% increase in yield-scaled GHG emissions, which was lower in semi-arid regions with medium and high N inputs. For PM systems, yield-scaled GHG emissions in medium N input decreased by 19-31% compared to high N input. Importantly, the yield-scaled GHG emissions in maize was always lower than in wheat. In future, in order to achieve global food and environmental security, it may be advisable to adopt PM in semi-arid regions with medium N input, especially for maize production, based on managing the tradeoffs among yield increase, yield-scaled GHG emissions, and increase in yield-scaled GHG emissions. (C) 2017 Elsevier Ltd. All rights reserved.