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The dry-hot wind climate is one of the major agro-meteorological disasters associated with high temperature, low humidity, and specific wind forces, which seriously affects the yield of wheat in the North China Plain. A field experiment was conducted to investigate the field microclimate, net photosynthetic rate, chlorophyll content of flag leaves, grain filling rate, and wheat yield after sprinkler misting under the condition of a dry-hot wind climate in the 2018 and 2019 seasons. Two travel speeds, full and half speed, and the corresponding irrigation amounts of 2.5 and 5 mm were used by a center pivot irrigation system during dry-hot wind conditions. A treatment without irrigation was applied as a control. The results showed that the air temperature and relative air humidity were greatly improved within 60 min after irrigation, especially in the upper part of the canopy. The net photosynthetic rate of flag leaves under 5 mm irrigation was higher than that under 2.5 mm irrigation during the middle and late grain filling periods. The adverse effects of dry-hot wind on the chlorophyll content of the flag leaves were mainly concentrated in the late grain filling stage. In the two years of the experiment, the average 1000-grain weights of 5 and 2.5 mm of irrigation treatments were 4.3 and 2.8% higher, and the grain yields were 5.8 and 3.3% higher, respectively, than those of the non-irrigated yields. Overall, applying a small amount of water between 12:00–14:00 with a center pivot before the occurrence of dry-hot wind is an effective means to regulate the field microclimate and produce more yield in the North China Plain.

High efficient nitrogen (N) application method and proper N management strategies can further reduce the losses and enhance N use efficiency. Field experiments were conducted in the 2015–2016 and 2016–2017 growing seasons to evaluate the effects of four fertigation frequencies treatments (FT-1: all the topdressing N was applied at the jointing stage; FT-2: 67% and 33% of the topdressing N was applied at the jointing and filling stages; FT-3: 33%, 50% and 17% of the topdressing N was applied at the regreening, jointing and filling stages; FT-4: 33%, 33%, 17% and 17% of the topdressing N were applied at the regreening, jointing, anthesis and filling stages) on wheat yield, water use efficiency (WUE), partial productivity of N fertilizer (PFPN) and N harvest index (NHI). In addition, one-time topdressing by surface broadcasting at the jointing stage was set up as a control (BC-1). The results showed that FT-3 and FT-4 supplied sufficient NO3−-N in the 0–40 cm soil layer, which reduced the risk of soil NO3−-N leaching to the deeper layers. FT-4 had the highest grain yield, WUE, PFPN and NHI, with average values of 9153.4 kg ha−1, 2.1 kg m−3, 0.74 kg kg−1 and 31.3 kg kg−1, respectively, followed by these values corresponding to the FT-3 in two years. These findings suggest that topdressing N split with 3–4 times, that is to say applying approximately 16.7% of topdressing N in anthesis and filling stages, respectively by the center pivot fertigation method can significantly improve yield, WUE, PFPN and NHI.

The projected climate change substantially impacts agricultural productivity and global food security. The cropping system models (CSM) can help estimate the effects of the changing climate on current and future crop production. The current study evaluated the impact of a projected climate change under shared socioeconomic pathways (SSPs) scenarios (SSP2-4.5 and SSP5-8.5) on the grain yield of winter wheat in the North China Plain by adopting the CSM-DSSAT CERES-Wheat model. The model was calibrated and evaluated using observed data of winter wheat experiments from 2015 to 2017 in which nitrogen fertigation was applied to various growth stages of winter wheat. Under the near-term (2021–2040), mid-term (2041–2060), and long-term (2081–2100) SSP2-4.5 and SSP5-8.5 scenarios, the future climate projections were based on five global climate models (GCMs) of the sixth phase of the Coupled Model Intercomparison Project (CMIP6). The GCMs projected an increase in grain yield with increasing temperature and precipitation in the near-term, mid-term, and long-term projections. In the mid-term, 13% more winter wheat grain yield is predicted under 1.3 °C, and a 33 mm increase in temperature and precipitation, respectively, compared with the baseline period (1995–2014). The increasing CO2 concentration trends projected an increase in average grain yield from 4 to 6%, 4 to 14%, and 2 to 34% in the near-term, mid-term, and long-term projections, respectively, compared to the baseline. The adaptive strategies were also analyzed, including three irrigation levels (200, 260, and 320 mm), three nitrogen fertilizer rates (275, 330, and 385 kg ha−1), and four sowing times (September 13, September 23, October 3, and October 13). An adaptive strategy experiments indicated that sowing winter wheat on October 3 (traditional planting time) and applying 275 kg ha−1 nitrogen fertilizer and 260 mm irrigation water could positively affect the grain yield in the North China Plain. These findings are beneficial in decision making to adopt and implement the best management practices to mitigate future climate change impacts on wheat grain yields.

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