Xu Xiaojuan, Jiao Fusheng, Lin Dayi, Qiu Jie, Zou Changxin, Zhang Kun
Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environmental of the People's Republic of China, Nanjing, China.
School of Geography, Nanjing Normal University, Nanjing, China.
Front Plant Sci. 2024 Nov 26;15:1482077. doi: 10.3389/fpls.2024.1482077. eCollection 2024.
Ecological engineering can significantly improve ecosystem carbon sequestration. However, few studies have projected the carbon sink trends in regions where ecological engineering projects overlap and have not considered the different climate change conditions and land use scenarios. Using the ensemble empirical mode decomposition method and machine learning algorithms (enhanced boosted regression trees), the aims of this study to elucidate the stability of carbon sinks and their driving mechanisms in areas where ecological projects overlap and to predict the potential enhancement in carbon sinks under varying climate and human activity scenarios. The findings revealed that: (1) The carbon sinks clearly and steadily increased in regions where five ecological projects were implemented from 1982 to 2019. In contrast, the carbon sinks did not significantly increase in regions with two or three ecological projects. (2) As the number of ecological projects increased, the impact of human activities on the carbon sinks gradually decreased. In eastern China, rapid economic development and significant interference from human activities hindered the growth of carbon sinks. In contrast, in western China, the warming and humidification trend of the climate, large-scale afforestation, and other ecological projects have significantly improved carbon sinks. (3) The regions with five overlapping ecological projects exhibited the greatest enhancement and stability of carbon sinks under different scenarios. Compared with the SSP585 scenario, under the SSP126 scenario, the carbon sinks increased, and their stability was greater. Achieving carbon neutrality requires major ecological projects to account for the limitations imposed by climatic conditions. Instead of isolated projects or the implementation of single restoration measures, a comprehensive approach that uses the synergistic effects of combined ecological strategies is recommended.
生态工程可以显著提高生态系统的碳固存能力。然而，很少有研究预测生态工程项目重叠地区的碳汇趋势，并且没有考虑不同的气候变化条件和土地利用情景。本研究采用集合经验模态分解方法和机器学习算法（增强型梯度提升回归树），旨在阐明生态项目重叠地区碳汇的稳定性及其驱动机制，并预测在不同气候和人类活动情景下碳汇的潜在增强情况。研究结果表明：（1）1982年至2019年实施五个生态项目的地区，碳汇明显且稳定增加。相比之下，实施两个或三个生态项目的地区碳汇没有显著增加。（2）随着生态项目数量的增加，人类活动对碳汇的影响逐渐减小。在中国东部，经济快速发展和人类活动的显著干扰阻碍了碳汇的增长。相比之下，在中国西部，气候变暖和湿润的趋势、大规模造林和其他生态项目显著改善了碳汇。（3）五个生态项目重叠的地区在不同情景下碳汇增强和稳定性最大。与SSP585情景相比，在SSP126情景下，碳汇增加，且稳定性更高。实现碳中和需要重大生态项目考虑气候条件带来的限制。建议采用综合方法，利用综合生态策略的协同效应，而不是孤立的项目或单一恢复措施的实施。
