Effects of different mulching technologies on rainfed maize field energy exchange and evapotranspiration partitioning in northwest China

•Total field water consumption was not significantly different between four soil mulching treatments.•Mulch reduced soil evaporation and increased the soil water storage at the maize early stage.•Mulch increased transpiration and accelerated the water consumption of depth soil due to faster plant growth.•Redistribution of available energy and ET partitioning were affected by maize LAI with a threshold of around 4 m2 m−2. Artificial mulching, a prevalent water-saving tool in arid and semiarid agroecosystems, complicated energy exchange and water transport process between land surface and atmosphere. The field energy and evapotranspiration (ET) partitioning within a soil-mulch-plant-atmosphere continuum have not been comprehensively examined, which limited cognition of the underlying mechanisms that control hydrological processes and achieve yield improvement. Here, a four-season experiment in a rainfed summer maize field with four mulching treatments (NM: non-mulching, SM: straw mulching, RPBF: plastic-mulched ridge with bare furrow, and RPSF: plastic mulched ridge with straw-mulched furrow) was conducted to study the dynamics of surface energy and ET components and their regulation mechanisms. Results indicated that the effects of mulching on field energy partitioning were most evident at the maize initial stage, during which net radiation was significantly decreased under PM treatments (RPBF and RPSF), while soil heat flux was significantly reduced in SM treatments (p