Effects of aerated drip irrigation and degradable film mulching on growth and water use of maize

Xinjiang is a typical arid area in China with scarce precipitation and intense water evaporation. Plastic film mulching increases temperature, preserves moisture, prevents weed growth, inhibits water evaporation, and improves crop yield. However, with the overuse of traditional plastic film, residual plastic film is constantly increasing in farmland, which has led to negative impacts, such as environmental pollution and decreased soil aeration. This study aimed to explore the effects of aerated drip irrigation and degradable film mulching on the growth and yield of maize and to reveal the compensation mechanism of aerated irrigation on maize yield reduction under degradable mulching film. Three kinds of films (oxidative biodegradable plastic films with induction periods of 60 and 100 days, and traditional polyethylene film) and two irrigation methods (aerated drip irrigation and non-aerated drip irrigation) were set up for a complete combination experiment to analyze the effects of different treatments on the growth, photosynthetic characteristics, yield, and water use efficiency of maize. The results showed that the cracks initially appeared 50 and 70 days after mulching under biodegradable plastic films mulching with induction periods of 60 and 100 days, respectively. Compared to traditional plastic mulching, maize yield and water use efficiency (WUE) under degradable plastic mulching were significantly reduced by 14.81%–27.42% and 16.70%–34.46% (P<0.05), respectively. Aerated drip irrigation increased plant height, stem diameter, and leaf area index, and reduced water consumption of maize. Compared to non-aerated drip irrigation, the net photosynthetic rate, transpiration rate, stomatal conductance, and dry matter accumulation of maize significantly increased under aerated drip irrigation by 10.40%, 12.86%, 25.99%, and 7.57% (P<0.05), respectively. Aerated drip irrigation significantly increased maize yield and WUE by 6.44%–14.41% and 9.09%–17.90% on average (P<0.05) under degradable mulching film and plastic mulching film, respectively. The decline in yield and WUE caused by premature degradation due to degradable film mulching was reduced by aerated drip irrigation. It was concluded that aerated drip irrigation combined with oxidative biodegradable film with an induction period of 100 days can replace the traditional drip irrigation of maize under plastic film mulching in the oasis of Xinjiang. This study provides a theoretical basis for reducing residual film pollution and improving maize yield and water use efficiency by aerated drip irrigation under mulch in Xinjiang.