Satellite-Based Quantification of Nitrogen Dioxide Effects on Vegetation Productivity in China

二氧化氮(NO2)是一种对植物有害的污染物，它通过破坏植物细胞直接影响植物的生长，并通过促进臭氧的形成间接影响植物的生长。尽管田间试验已经证实空气污染会显著影响作物生长，但由于观测数据有限，二氧化氮对不同类型植被生产力的大规模影响仍然知之甚少。在本研究中，我们采用创新方法，综合卫星观测数据，研究氮氧化物对中国植被生产力的影响。研究结果表明，NO2浓度与植被生产力之间存在较强的负相关。不同类型的植被对NO2的敏感性差异较大。其中，草原对NO2的敏感性最高，而常绿针叶林和灌木林对NO2的敏感性最低。当NO2浓度降低至第5百分位数时，农田、草原、灌木林、混交林、落叶阔叶林和常绿针叶林的生产力预计分别提高27.73%、14.71%、12.50%、4.28%、3.58%和3.21%。这些结果与野外实验的结果一致，加强了我们方法的有效性。该研究凸显了卫星观测在量化区域范围内空气污染对植被生长影响方面的潜力。Nitrogen dioxide (NO2) is a phytotoxic pollutant that affects plant growth both directly, by damaging vegetation cells, and indirectly, by contributing to ozone formation. While field experiments have demonstrated the significant impact of air pollution on crop growth, the large-scale effects of NO₂ on vegetation productivity across diverse plant species remain poorly understood due to limited observational data. In this study, we investigated the influence of NO₂ on vegetation productivity across China using an innovative approach that integrates satellite-based observations. Our findings revealed a strong negative correlation between NO₂ concentrations and vegetation productivity, indicating that elevated NO₂ levels are associated with reduced plant growth. The sensitivity of vegetation types to NO₂ varied considerably, with savannas being the most sensitive and evergreen needleleaf forests and shrublands the least. Specifically, reductions in NO₂ concentrations to the 5th percentile were estimated to increase productivity by 27.73% in croplands, 14.71% in savannas, 12.50% in shrublands, 4.28% in mixed forests, 3.58% in deciduous broadleaf forests, and 3.21% in evergreen needleleaf forests. These results are consistent with those from field experiments, reinforcing the validity of our approach. This study highlights the potential of satellite observations for quantifying the effects of air pollution on vegetation growth at regional scales.