Assessment of the sustainability of groundwater utilization and crop production under optimized irrigation strategies in the North China Plain under future climate change

Authors: TAN, LILI - China Agricultural University; ZHANG, XUELIANG - China Agricultural University; QI, JUNYU - University Of Maryland; SUN, DANFENG - China Agricultural University; Marek, Gary; FENG, PUYU - China Agricultural University; LI, BAOGUI - China Agricultural University; LIU, DE LI - Wagga Wagga Agricultural Institute; LI, BAOGUO - China Agricultural University; SRINIVASAN, RAGHAVAN - Texas A&M University; CHEN, YONG - China Agricultural University

Submitted to: Science of the Total Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/16/2023
Publication Date: 7/20/2023
Citation: Tan, L., Zhang, X., Qi, J., Sun, D., Marek, G.W., Feng, P., Li, B., Liu, D., Li, B., Srinivasan, R., Chen, Y. 2023. Assessment of the sustainability of groundwater utilization and crop production under optimized irrigation strategies in the North China Plain under future climate change. Science of the Total Environment. 899. Article 165619. https://doi.org/10.1016/j.scitotenv.2023.165619.
DOI: https://doi.org/10.1016/j.scitotenv.2023.165619

Interpretive Summary: Climate change may pose a substantial risk to global food security and groundwater resources in irrigated and rainfed crop production regions. Simulation modeling using global circulation models can provide insight into alternative irrigation management strategies that mitigate the effects of climate change. Researchers from USDA-ARS Bushland and university partners from the U.S., Australia, and China simulated the effects of limited irrigation strategies on groundwater decline and crop yields under double cropping in the North China Plan (NCP) through the 21st century. Simulations using a Soil and Water Assessment Tool (SWAT) model equipped with improved CO2 and irrigation management modules showed that groundwater levels could be stabilized by adopting targeted irrigation at jointing for winter wheat followed by rainfed management for maize. This study further highlighted the efficacy of the improved SWAT model for evaluating alternative management strategies to reduce negative impacts of climate change.

Technical Abstract: Over-exploitation of groundwater due to conventional irrigation of double-cropped winter wheat and summer maize and anticipated climate change impacts pose major threats to the water and food security in the North China Plain (NCP) region. In this study, the Soil and Water Assessment Tool (SWAT) model equipped with an improved auto-irrigation algorithm, groundwater module, and dynamic CO2 input (SWAT-GW-CO2) was used to simulate climate change impacts on shallow groundwater level and winter wheat and summer maize production under limited irrigation strategies to suggest optimal management strategies under future climate conditions in the NCP. The SWAT-GW-CO2 model was successfully evaluated using measured data from the region collected during 1993-2017. In addition, simulations of eleven limited irrigation strategies for winter wheat with targeted irrigations at different growth stages and with irrigated or rainfed summer maize were compared with future conventional irrigation management. Projected climate change from 22 general circulation models (GCMs) and three Shared Socioeconomic Pathways (SSP1-2.6, SSP2-4.5, and SSP5-8.5) were used to drive the SWAT-GW-CO2 model. Climate change impacts showed that mean winter wheat (summer maize) yield under adequate irrigation was expected to increase by 13.2 percent (4.9 percent) during the middle time period (2041 to 2070) and by 11.2 percent (4.6 percent) during the late time period (2071 to 2100) under three SSPs as compared to the historical period (1971 to 2000). Mean decline rate of shallow groundwater level slowed by approximately 1 m a-1 during the entire future period (2041-2100) under three SSPs with a greater reduction for SSP5-8.5. The average contribution rate of future climate toward the balance of shallow groundwater pumping and replenishment was 62.9 percent. Based on the simulated crop yields and decline rate of shallow groundwater level, the most appropriate limited irrigation was achieved by applying irrigation during the jointing stage of wheat with rainfed maize, which could also achieve the balance of groundwater extraction and replenishment.