Ridge-furrow mulching system regulates hydrothermal conditions to promote maize yield and efficient water use in rainfed farming area

Abstract The ridge-furrow mulching system with plastic film (RFMS) is considered an effective strategy to improve grain yield and has been widely used in arid and semi-arid rainfed agricultural areas. However, the key mechanism by which RFMS increases yield and efficiency under different hydrothermal conditions remains unclear. Understanding this mechanism and the interaction between different RFMSs and hydrothermal conditions could provide a practical reference for optimizing cultivation. We aimed to investigate the yield increase potential of different planting systems under the same hydrothermal conditions and evaluate the effects of RFMS treatments on drought resistance and yield increase under different hydrothermal conditions. The following planting treatments were carried out in ridge–furrow prepared fields under seven different hydrothermal conditions in a representative rainfed agricultural area for four consecutive years: 1) ridge-furrow mulching system with complete coverage (RC); 2) ridge-furrow mulching system with ridge coverage (RR); and 3) planting without mulching (control treatment; CT). Compared with CT, RFMS improved field hydrothermal conditions and reduced evapotranspiration of crops. In more hydrothermally limited areas (precipitation, 196–320 mm; temperature,