Effects of mulching cultivation patterns on grain yield, resources use efficiency and greenhouse gas emissions of rainfed summer maize on the Loess Plateau of China

Soil mulching, an efficient practice for enhancing crop productivity, has been widely used in agricultural production in the arid and semi-arid regions worldwide. A two-season (2023 and 2024) field experiment was conducted on rainfed summer maize on the Loess Plateau of China, including six mulching cultivation patterns: flat cultivation with no mulching (NM), flat cultivation with full straw mulching (SM), ridge-furrow cultivation with transparent film mulching over the ridge (RP), ridge-furrow cultivation with transparent film mulching over continuous ridges (DMt), ridge-furrow cultivation with silver-black film mulching over continuous ridges (DMs), and ridge-furrow cultivation with black film mulching over continuous ridges (DMb). The results showed that soil mulching significantly affected the soil hydrothermal conditions within the 0–25 cm soil layer and significantly decreased crop evapotranspiration. DMb obtained the highest grain yield, followed by DMs. Compared to NM, DMb significantly increased leaf area index, above-ground biomass, 1000-grain weight, grain yield, water productivity, thermal time use efficiency, and radiation use efficiency by 31.3 %, 41.8 %, 26.2 %, 51.1 %, 49.6 %, 42.1 %, and 18.3 %, respectively. DMt had the highest greenhouse gas emission index (GHGI), while the GHGI of DMb was 52.4 % lower than that of DMt. Overall, DMb optimized soil hydrothermal conditions and facilitated above-ground biomass and water-heat-radiation use efficiency, significantly improving grain yield of rainfed summer maize while maintaining relatively low GHGI, which was a sustainable agricultural strategy for rainfed maize production on the Loess Plateau.