生态区
温室气体
环境科学
土壤水分
沉积(地质)
大气科学
一氧化二氮
土壤碳
中国
自然地理学
土壤科学
地理
生态学
地质学
考古
沉积物
古生物学
生物
作者
Xiaoyu Cen,Mingxu Li,Li Xu,Jianxing Zhu,Nianpeng He
摘要
Nitrous oxide (N2O) is an influential greenhouse gas (GHG) and an unregulated ozone-depleting substance. The extent to which N2O emissions from natural forest soils have been enhanced by high atmospheric nitrogen (N) deposition in China during past decades is unclear; however, assessing land-related N2O emissions for 2060 national “carbon neutrality” goal is urgent. In this study, we proposed a “gray box” conceptual model and deduced a linear relationship between soil N2O emissions and N deposition on a large scale. On this basis, we created a “process-augmented data-driven” approach using which we combined experimental N addition data from 38 Chinese forests with N deposition observation data to estimate regional soil N2O emissions. We found that the N2O emission budget of eastern China forest soils averaged 0.24 ± 0.07 TgN yr−1 from 1996 to 2015; of this, ∼36% (0.087 TgN yr−1) was directly induced by N deposition. Soil N2O emission rates (RN2O) fluctuated slightly after 2006, and the RN2Os of different ecoregions were significantly different (p < 0.001). Soil factors and N-deposition-related factors dominated the spatial variation of RN2O. Our findings provide country-specific and ecoregion-specific emission factors for national GHG inventories in China. Our approach bridges the gap between site-level experiments and demand for regional N2O emissions, and is applicable for estimating N2O emissions in other countries/regions. Meanwhile, more N addition experiments are needed to comprehensively understand N cycling processes and extend the predictive capability of the approach.
科研通智能强力驱动
Strongly Powered by AbleSci AI