Abstract:
How to increase maize yield and reduce residual film pollution remains an issue urgently needing to be addressed in maize production in the semi-arid region of the Loess Plateau. This study was conducted at the Rainfed Agricultural Experiment Station of Gansu Agricultural University in Gansu Province, China during the 2023–2024 growing seasons. The experimental design included two factors: plastic film utilization methods (T1: new film; T2: two-year reuse of plastic film with no-till) and plastic film thickness (H1: 0.01 mm; H2: 0.015 mm; H3: 0.02 mm), with a total of 6 treatments.The effects of mulch film thickness and two-year reuse of plastic film with no-till on maize yield, water use efficiency (WUE) and mulch film recovery rate in central Proving dryland were studied. The results showed that compared with the two-year reuse of plastic film with no-till, new plastic film under H1, H2, and H3 significantly increased the average soil temperature in the 0-25 cm layer during the seedling to jointing stage by 6.71%、5.60%, and 5.77%, respectively. From jointing to maturity stages, no significant differences in average soil temperature in the 0-25 cm layer were observed between new film and two-year reuse of plastic film with no-till. However, under H2 and H3 thicknesses, two-year reuse of plastic film with no-till did not significantly reduce soil water storage during these periods. Both new film and two-year reuse of plastic film with no-till treatments showed no significant differences in harvest biomass or yield between H2 and H3. Compared with the new film treatment, the two-year use of no-tillage film reduced the biomass and yield at maturity by 27.18% and 24.1%, respectively under H1 thickness, respectively. Thicker films (H2 and H3) significantly increased WUE by 26.78% and 29.71% compared to H1. Under new film, the net income or ratio of output to input were not significant differences among H1, H2, and H3. Under two-year reuse of plastic film with no-till, compared to H1, H2 and H3 increased net income by 45.74% and 46.10%, respectively, and elevated the ratio of output to input by 11.11% and 9.63%, respectively. Although two-year reuse of plastic film with no-till significantly reduced the film recovery rate compared to new film, thicker films under two-year reuse with no-till significantly improved the recovery rate compared to H1. These results indicate that under new film, thicker films did not significantly increase yield or net income; however, thicker films under two-year reuse with no-till significantly enhanced both yield and net income. Therefore, considering yield, WUE, film recovery, and economic benefits, the 0.015mm plastic film combined with two-year reuse of plastic film under no-till is a suitable plastic film measure for arid agricultural areas on the Loess Plateau.