Exploring optimal soil mulching to enhance yield and water use efficiency in maize cropping in China: A meta-analysis

Global crop yields are limited by the shortage of water resources and nutrient availability. Mulching technology can effectively modify the crop growth environment and crop production due to differences in climatic conditions, spatial distribution characteristics, and cropping systems. Hence, we conducted a meta-analysis to evaluate the eff;ects of plastic mulching (PM) and straw mulching (SM) on the yield and water use efficiency (WUE) of maize cropping in China using data obtained from 176 peer-reviewed publications. The results showed that plastic mulching significantly increased maize yield (29.24%) and WUE (29.45%). The eff;ects of mulching on maize were also improved by 12.02% (yield) and 11.43% (WUE). At the regional scale, maize yield and WUE were influenced by diff;erent planting regions and mulching management practices. Plastic mulching performed best in the North maize region and the Huanghuaihai maize region of China, while straw mulching performed better in the Southern hilly maize region of China. Plastic mulching was the best way to increase maize yield (59.56%) and WUE (29.91%) with mulching in fallow period, and straw mulching was the best way to increase maize yield (12.43%) and WUE (13.21%) with mulching in the growth period. Full plastic mulching could significantly increase maize yield (42.06%), and among different amounts of straw, mulching with 10-15 t ha(-1) performed the best, boosting the maize yield by 13.35%. Transparent film and ridge row mulching were more favorable to maize growth and increased crop yield and WUE in the arid and low temperature areas of China. In conclusion, plastic mulching can significantly increase maize yield and WUE, the adoption of mulching practices and management practices has more application prospects.