Adaptation of sprinkler irrigation scheduling and winter wheat variety to cope with climate change in the North China Plain

Abstract

Climate change and water shortage have brought great challenges to agricultural production in the North China Plain, and it’s crucial to find the suitable method to address these challenges. Climate model projections were used to drive the Agro-Hydrological & chemical and Crop systems simulator (AHC) that considering the impact of irrigation on field microclimate. Yield, evapotranspiration (ET), water productivity (WP), and the impact on groundwater level of 6 wheat varieties under 6 sprinkler irrigation scheduling (IS1: no irrigation; IS6: full irrigation without water deficit; IS2–5: deficit irrigation with 0.2, 0.4, 0.6, and 0.8 times water of IS6 after wheat greening) were estimated in Xingtai under current and two shared social economic paths scenarios (SSP2–4.5 and SSP5–8.5). The optimal combination of irrigation and variety (OC) was selected by Topsis method. The results indicated that AHC had a high accuracy in simulating the growth of six varieties (R2>0.80, NRMSE<20 %) after parameter optimization. The temperature, solar radiation, and precipitation in 2021–2100 increased by 0.1–2.8 °C, 0.7–1.7 MJ m−2 d−1, and 5.2–28.8 mm under SSP2–4.5 and 0.2–4.8 °C, 0.9–1.2 MJ m−2 d−1, and 4.7–73.1 mm under SSP5–8.5 than current climate. As the irrigation amount increased, the simulated yield and ET increased, while WP first increased and then decreased. Due to climate change, irrigation failed to improve the wheat potential yield after 2080 under SSP2–4.5 and 2060 under SSP5–8.5. The OC implied that “Shimai26” and IS5 and IS4 in the future were the best strategy. It saved water by 13–23 % with similar yield than full irrigation. Moreover, the inhibitory effect of OC on annual groundwater level drawdown was stronger than other irrigation by 0.04–0.24 m. These findings were beneficial for mitigating climate impacts on grain yields in water scarce areas.

Keywords

• Sprinkler irrigation scheduling
• Wheat variety
• Climate change
• North China Plain
• Wheat yield