Impact of Plastic Film with Wheat Straw Mulching on Maize Water Use Efficiency, Evapotranspiration, and Grain Yield in Northern China: a Meta-analysis

Soil degradation and water scarcity are key constraints underlying low crop productivity in arid and semiarid regions. Therefore, adoption of improved technologies and effective management practices for optimizing soil water conservation and improving soil fertility is crucial for sustainable food production in dryland areas. A meta-analysis using the preferred reporting items for systematic reviews and meta-analyses guideline was performed to synthesize studies investigating the impact of plastic film and wheat straw mulching on maize water use efficiency (WUE), evapotranspiration, and grain yield in northern China. Articles published from 2001 to 2021 were examined to investigate the influence of mulching and ridge-furrow rainwater harvesting systems on maize grain yield. The meta-analysis demonstrated that the plastic mulched ridge with straw mulch furrow increased maize grain yield and water use efficiency in low rainfall areas. Compared to traditional flat planting (TFP) with no mulching, plastic film mulch with straw mulched furrow (PMR + SMF) treatment significantly ( p = 0.0008) increased WUE of maize by 69.51% in areas where air temperature was < 10 °C but had no significant effect on evapotranspiration. Maize grain yield in Shaanxi and Gansu areas increased significantly (by 52.52%, p < 0.00001) with the integration of PMR + SMF system compared to the TFP with the no mulching. However, the plastic film mulch and wheat straw mulch acting solely or in combination did not significantly affect maize evapotranspiration under the different climate and soil types investigated. The integration of RFRHs with plastic film with wheat straw mulching can improve crop productivity and WUE. Findings from the meta-analysis lay a platform for the adoption of climate-smart integrated soil water management practice in semiarid areas to strengthen climate-resilient crop production.