Shang Fang, Liu Mingxu, Song Yu, Lu Xingjie, Zhang Qiang, Matsui Hitoshi, Liu Lingli, Ding Aijun, Huang Xin, Liu Xuejun, Cao Junji, Wang Zifa, Dai Yongjiu, Kang Ling, Cai Xuhui, Zhang Hongsheng, Zhu Tong
State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, 100871, Beijing, China.
Institute of Atmospheric Physics, Chinese Academy of Sciences, 100029, Beijing, China.
Nat Commun. 2024 Sep 4;15(1):7738. doi: 10.1038/s41467-024-52152-5.
China faces challenges in reaching its carbon neutrality goal by the year 2060 to meet the Paris Agreement and improving air quality simultaneously. Dramatic nitrogen emission reductions will be brought by this ambitious target, yet their impact on the natural ecosystem is not clear. Here, by combining two atmospheric chemistry models and two process-based terrestrial ecosystem models constrained using nationwide measurements, we show that atmospheric nitrogen deposition in China's terrestrial land will decrease by 44-57% following two emission control scenarios including one aiming at carbon neutrality. They consequently result in a pronounced shrinkage in terrestrial net ecosystem production, by 11-20% depending on models and emission scenarios. Our results indicate that the nitrogen emission reductions accompanying decarbonization would undermine natural carbon sinks and in turn set back progress toward carbon neutrality. This unintended impact calls for great concern about the trade-offs between nitrogen management and carbon neutrality.
中国在到2060年实现碳中和目标以履行《巴黎协定》并同时改善空气质量方面面临挑战。这一宏伟目标将带来大幅的氮排放减少，但其对自然生态系统的影响尚不清楚。在此，通过结合两个大气化学模型和两个基于过程的陆地生态系统模型，并利用全国范围内的测量数据进行约束，我们表明，在中国陆地，包括一个以碳中和为目标的两种排放控制情景下，大气氮沉降将减少44% - 57%。这相应地导致陆地生态系统净生产量显著减少，根据模型和排放情景的不同，减少幅度为11% - 20%。我们的结果表明，脱碳过程中伴随的氮排放减少将破坏自然碳汇，进而阻碍碳中和进程。这种意外影响需要人们高度关注氮管理与碳中和之间的权衡。
