近地层臭氧对我国树木生产力和作物产量的影响:进展与展望

Effects of ground-level ozone on tree productivity and crop yield in China:progress and prospect

大气污染严重威胁了我国陆地生态系统的固碳能力,但随着减污降碳协同治理的快速推进,减缓大气污染将有利于提升陆地碳汇,并切实推动碳达峰碳中和目标的实现。为了更好地理解大气污染与生态系统固碳的关系,本文以主要空气污染物臭氧(O_(3))为例,基于田间控制实验的整合分析、剂量响应关系及机理模型三种评估方法综述了近地层O_(3)污染对植被碳固定影响的最新进展。尽管不同作物种类以及品种、不同功能型木本植物对O_(3)的响应有着显著的差异,且各种方法的评估结果也不尽相同,但目前O_(3)浓度造成我国粮食作物减产、森林生产力降低已是不争的事实。持续升高的O_(3)浓度将严重威胁我国陆地生态系统的固碳能力。利用我国作物和树木的O_(3)剂量响应方程进行评估的结果表明,在CO_(2)减排和O_(3)污染协同治理下,预计2060年我国树木生物量和作物产量将比当前显著提高,增加陆地生态系统碳汇,助力碳中和目标。最后,对如何提高O_(3)污染环境下植物固碳能力也进行了展望。

Air pollution has threatened the terrestrial ecosystem carbon sink capacity in China.With synergetic control of environmental pollution and carbon emission,mitigation of air pollution would drive improvements of terrestrial carbon sink and contribute to emission peak and carbon neutrality targets.To better understand the relationships between air pollution and terrestrial carbon sink,this review summarizes existing results related with tropospheric ozone(O_(3))effects on plant carbon sequestration based on meta-analysis,dose-relative biomass/yield and earth system modeling.Responses of different crops,cultivars and plant functional types to elevated O_(3) were significantly different.These effects were also changed by estimation approaches.Results indicated that ambient O_(3) in China has induced losses of crop yield and forest productivity.Rising O_(3) concentration has seriously threaten the terrestrial ecosystem carbon sink capacity in China.On the other hand,synergetic control of environmental pollution and carbon emission will increase forest productivity and crop yield in 2060 compared tO_(2)020,estimated from the dose-relative biomass/yield relationship based on plants grown in China.The contributions of terrestrial ecosystem to carbon neutrality will be increased if ambient ozone is reduced.Lastly,we proposed how to improve the carbon sequestration under O_(3) pollution.