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Plastic film mulching (PM) has been extensively used to increase crop yields in dryland regions in China. However, the impact of differently colored PM on crop radiation utilization due to the optical properties of the underlying PM surfaces remains unclear. We conducted a two-year field experiment in northwest China to evaluate the dynamics of photosynthetically active radiation interception and absorption (fIPAR and fAPAR), as well as the radiation use efficiency for intercepted and absorbed radiation (RUE i and RUE a) during spring maize (Zea mays L.) growth periods. Two fertilization levels (high and low) and 3 PM treatments (transparent film, black film, and no film) were considered in this study. We also developed empirical regression functions to calculate canopy fAPAR, accounting for both canopy and underlying surface characteristics. Furthermore, we used canopy absorption radiation to drive the Soil-Plant-Atmosphere Continuum System (SPACSYS) model to simulate maize biomass and yield. We found that transparent film mulching (TM) exhibited higher fIPAR and fAPAR than black film mulching and no mulching (CK). TM had an increase of RUE i and RUE a by 10.6% and 9.7%, respectively, relative to CK, resulting in a 9.3–19.2% increase in maize yield and a 25.8–30.2% increase in the partial factor productivity of nitrogen. These increases were mainly attributed to the increased relative chlorophyll content, net photosynthesis rate, and extended grain-filling period under TM. We found that the modified radiation input increased the accuracy of the SPACSYS model in simulating maize biomass and yield. We underscore the importance of using TM in dryland areas to increase crop yields and advocate for incorporating canopy radiation data into crop models, especially in agricultural regions where plastic film mulching is used, to enhance the accuracy of yield simulations. • Transparent film mulching (TM) with high nitrogen produced the highest maize yield. • TM increased light intercept and absorbed fraction (fAPAR). • We established empirical regression functions to calculate canopy fAPAR. • Soil–Plant–Atmosphere Continuum System (SPACSYS) model well simulated yield with modified radiation input data. [ABSTRACT FROM AUTHOR]

Plastic film mulching (PM) is a useful agronomic means to adapt to the environmental conditions of dryland agriculture and improve crop production. To improve the theoretical framework of PM technology, this study focuses on the interaction between the soil temperature change caused by PM and crop growth. The definition, action mechanism, and simulation of the compensatory effect of PM on growing degree days are introduced to reveal the effect of soil temperature under PM on crop development and growth. Our summary shows that the strength of the warming effect changes with the growth and development of crops, strengthening during the early stage of crop growth and gradually weakening as a crop canopy develops. Generally, the warming effect has a good promotion effect on crop growth, but the crop growth is hampered even with a yield reduction when the increased soil temperature caused by PM exceeds the tolerant temperature for plant growth. Moreover, the compensatory effect of PM could be used to quantify the growth and development of crops under PM and has been widely applied to cotton, corn, winter wheat, and rice. The compensation coefficient is larger in the early stage of crop growth than in the later stage. The compensation coefficient has certain differences for the same crop because of the influence of climate factors, soil moisture content, and soil microtopography. In future research, the theoretical integration of the safety period of PM and the time threshold of the compensatory effect could be theoretically interpreted, and the construction of the compensatory effect module in the crop models will also be an important issue. [ABSTRACT FROM AUTHOR]

Plastic film mulching (PM) has become a widely used cropping method in arid and semiarid areas. However, it is unknown how different PMs affect crop water and N utilization and their interaction under different N supplies. A two-year field experiment was conducted in the Hetao Irrigation District (HID), in northwest China. Following local irrigation practices, 500 mm border irrigation was used to grow spring maize over two growing seasons (2019 and 2020) with two N levels: high-N (225 kg N ha–1) and low-N (150 kg N ha–1). Combined with three mulching methods, the experiment had five treatments: (i) no mulching with high-N (control, CK), (ii) black plastic film with high-N (HB), (iii) transparent plastic film with high-N (HT), (iv) black plastic film with low-N (LB), and (v) transparent plastic film with low-N (LT). The 4 PM treatments had higher average soil water storage (0–120 cm) than CK. The PM treatments had the highest water consumption coefficients (K wcn) at 6–leaf to 12–leaf stage (K wc2) and milking to maturity (K wc5) stage. The HP treatments (HB and HT) had higher soil nitrogen storage than CK during the growth period. Averaged across two seasons, HB and HT had 23.9%, 29.2% respectively, higher grain yields than CK. Averaged across two seasons, the transparent PM treatments had 7.49%, 5.31%, and 1.72% higher water use efficiency (WUE), partial factor productivity of nitrogen (PFPN), and harvest index, respectively, than the black PM treatments. The PM treatments showed the relationship between water use efficiency of biomass (WUE b) and nitrogen use efficiency of biomass (NUE b), with WUE b increased, NUE b also increased. Given these results, we recommend the high-N level and transparent PM for maize cropping to increase yield and resource utilization efficiency in the HID. • Plastic film mulching (PM) redistributed soil water and NO3--N and created a better rootzone soil environment. • PM improved WUE b , accelerated maize soil nitrogen utilization and dry matter accumulation. • Transparent film mulching produced higher yield and resource use efficiency than black film and no mulching. • PM is a promising practice for water and nitrogen management in arid agricultural systems. [ABSTRACT FROM AUTHOR]

Future climate change (FCC) and water scarcity significantly affect agricultural production in arid areas. Plastic film mulching (PM) combined with large irrigation amounts is popular for agricultural production in these areas. Crop model is an important tool for studying FCC's effect on crop production and its countermeasures. In this study, after calibration and validation using measured values from a two-year field experiment, the SPACSYS (v 6.0) and modified DSSAT-CERES-Maize (v 4.7.0.0) models were used to evaluate the implementation of six management systems (three mulching measures: transparent film, black film, no film; two fertilization levels: high, low) and to optimize management measures under FCC. Both models well simulated maize's anthesis and maturity dates, the final aboveground biomass, yield, and topsoil soil water content (SWC) compared with the measured values. SPACSYS simulated the maize growth and SWC under nitrogen stress better than DSSAT. Total 27 global climate models (GCMs) were used to drive DSSAT and SPACSYS models with different irrigation schemes, including three irrigation amounts (I1, I2, I3) and four irrigation ratios (the proportion of total irrigation amount in different growing stages: T1, T2, T3, T4) to simulate crop phenology and yield under FCC in future decades (2040s and 2080s). Both models advanced the anthesis date (by 8.1–16.2 d in the 2040s and 12.8–20.3 d in the 2080s), maturity date (by 12.7–18.9 d in the 2040s and 19.1–24.8 d in the 2080s), and length of reproductive growth period (by 3.6–6.1 d in the 2040s and 5.8–11.0 d in the 2080s). The I1T1 scenario under transparent film mulching produced the highest yields (12.14–16.07% in the 2040s and 5.36–6.07% in the 2080s higher than the average). The I3T4 scenario maintained stable yields in the 2040s, decreasing by nearly 20% in the 2080s. Consequently, the I3T4 scenario could be the optimal management practice for balancing yield and irrigation for maize production in this arid area in the future decades. • DSSAT and SPACSYS can reasonably simulate maize yield under plastic film mulching (PM). • SPACSYS and DSSAT showed advanced phenological dates and shorten the reproductive period under climate change. • The 400 mm irrigation schemes under PM achieved stable yields for future climate change. • PM is a long-term agricultural practice for arid agricultural systems. [ABSTRACT FROM AUTHOR]