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Abstract Climate change poses unprecedented challenges to agricultural sustainability, with profound implications for environmental quality and crop productivity. However, integrated assessments quantifying the specific contributions of climatic drivers versus management practices to agricultural ammonia (NH 3 ) emissions and crop yields remain limited in China, constraining precision air pollution control and threatening national food security. This study employed the DNDC model to simulate fertilizer-related NH 3 emissions and crop yields of China’s three major crops (rice, maize, and wheat) under current and three representative shared socioeconomic pathways (SSP) representative concentration pathways scenarios (SSP1-1.9, SSP3-7.0, and SSP5-8.5) for 2030, 2050, and 2060, while explicitly partitioning the relative importance of climate change versus nitrogen management variations to agricultural outcomes. Results indicate that fertilizer-related NH 3 emissions totaled 3.00 Tg N yr −1 in 2019, with a combined crop yield of 618.76 Tg. By 2060, fertilizer-related NH 3 emissions were projected to increase by 2.0%, 12.0%, and 84.3% under SSP1-1.9, SSP3-7.0, and SSP5-8.5, respectively, while crop yields would decrease by 16.7%, 16.1%, and 5.8%. Under SSP1-1.9, the relative importance of climate change for fertilizer-related NH 3 emissions (RI e ) maintained approximately 50% throughout 2030–2060, suggesting balanced offsetting effects between climate change and the projected nitrogen fertilizer reduction. Conversely, the relative importance of climate change for crop yields (RI y ) reached 91% by 2060, demonstrating that crop yield losses were predominantly driven by climatic stresses rather than the fertilizer input adjustment. Under SSP5-8.5, substantial increases in nitrogen fertilization reduced the relative importance of climate change, with RI e and RI y values dropping to 17% and 59% in 2060, respectively. This pattern demonstrates that enhanced fertilization could not fully offset crop yields losses, while 84% of fertilizer-related NH 3 emissions increases resulted from intensified fertilizer use. This study provides critical insights for precision emission reduction in agricultural-atmospheric systems and supports China’s dual goals of food security and carbon neutrality.
Mu et al. (Fri,) studied this question.