植物生态学报 ›› 2020, Vol. 44 ›› Issue (8): 854-863.DOI: 10.17521/cjpe.2020.0022

所属专题: 光合作用

• 研究论文 • 上一篇    下一篇

臭氧和气溶胶复合污染对杨树叶片光合作用的影响

李景1,2, 王欣1, 王振华1,2, 王斌1,2, 王成章1,2, 邓美凤1, 刘玲莉1,2,*()   

  1. 1中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
    2中国科学院大学, 北京 100049
  • 收稿日期:2020-01-18 接受日期:2020-06-03 出版日期:2020-08-20 发布日期:2020-07-10
  • 通讯作者: 刘玲莉
  • 作者简介:* lingli.liu@ibcas.ac.cn
  • 基金资助:
    国家自然科学基金(31670478);国家自然科学基金(31600389);国家自然科学基金(31522011)

Effects of ozone and aerosol pollution on photosynthesis of poplar leaves

LI Jing1,2, WANG Xin1, WANG Zhen-Hua1,2, WANG Bin1,2, WANG Cheng-Zhang1,2, DENG Mei-Feng1, LIU Ling-Li1,2,*()   

  1. 1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-01-18 Accepted:2020-06-03 Online:2020-08-20 Published:2020-07-10
  • Contact: LIU Ling-Li
  • Supported by:
    National Natural Science Foundation of China(31670478);National Natural Science Foundation of China(31600389);National Natural Science Foundation of China(31522011)

摘要:

由于经济的快速发展, 中国大部分地区正面临着严峻的复合型大气污染, 其中臭氧和气溶胶是两种主要污染物。已有的研究表明臭氧对叶片的氧化性伤害能够抑制光合作用, 而气溶胶可通过增加散射辐射比例或缓解高温抑制促进光合作用。但复合污染下, 臭氧和气溶胶如何共同调控叶片光合作用, 仍缺乏研究。该研究利用北京及周边地区之间的污染梯度, 选择加杨(Populus × canadensis)作为实验对象, 于2012-2013年生长季期间对叶片光合速率进行连续观测, 并同时监测臭氧浓度(AOT40)、气溶胶光学厚度(AOD)、空气温度和冠层内外光合有效辐射(PAR)等环境因子, 以期探讨大气复合污染下臭氧和气溶胶变化对植物叶片光合作用的影响及相关机制。结果表明: (1)臭氧浓度与空气温度、气溶胶浓度之间均呈显著正相关关系, 但气溶胶浓度与空气温度没有显著相关关系; (2)臭氧浓度增加显著抑制了阳生叶片的光合作用, 但气溶胶浓度上升促进了阳生叶片的光合作用; 臭氧浓度升高对阴生叶片光合作用的影响较小, 但气溶胶浓度上升促进了阴生叶片的光合作用; (3)标准化后的结果显示, 臭氧对阳生叶片光合作用的影响最大, 此时气溶胶的促进作用一定程度上补偿了臭氧浓度上升所带来的抑制效应。对于阴生叶片光合作用而言, 气溶胶则是最重要的影响因素。该研究发现复合污染下阴生叶和阳生叶光合响应不同, 这表明冠层结构可能通过影响阴生叶和阳生叶的比例, 从而对植物生长产生不同影响。该研究对理解大气复合污染如何影响光合作用提供了的机理支持, 同时也表明, 为了维持生态系统生产力及功能, 需要同时控制气溶胶和臭氧污染。

关键词: 复合型大气污染, 光合作用, 臭氧, 气溶胶, 阳生叶, 阴生叶

Abstract:

Aims The rapid economic growth has led to serious atmospheric compound pollution in China. Ozone and aerosol are the two main air pollutants that could greatly alter the photosynthesis of plants. Ozone often inhibits leaf photosynthesis through phototoxic effect, while aerosol could increase leaf photosynthesis through diffuse fertilization effect. This paper aims to investigate the relative impact of ozone and aerosol on leaf photosynthesis under atmospheric compound pollution.
Methods We planted Populus × canadensis at three sites along the air pollution gradient around Beijing metropolitan area. During the growing season of 2012-2013, ozone concentration (AOT40), aerosol optical depth (AOD), air temperature, photosynthetically active radiation (PAR) and photosynthetic rates of leaves were measured at these sites.
Important findings The results showed that: (1) AOT40 increased with increasing air temperature and AOD. Aerosol loadings reduced the external canopy PAR but increased internal canopy PAR. (2) The photosynthesis of sun leaves positively correlated with AOD and air temperature, and negatively correlated with AOT40, while the photosynthetic of shade leaves was positively correlated with AOD. (3) For sun leaves, ozone was the most important factor affecting their photosynthetic rates. Aerosol’s positive effect on photosynthesis of sun leaves was compensated by the negative effect of ozone. Meanwhile, by scattering solar radiation, aerosol contributed the most to the increased photosynthesis of the shade leaves. Overall, our results indicated that ozone and aerosol induced different impacts on the photosynthesis of sun and shade leaves, suggesting that plants with different canopy structures and ozone sensitivity may respond differently to compound pollution. Our results also indicated that aerosol and ozone pollution need to be controlled simultaneously to protect the productivity and function of ecosystem.

Key words: atmospheric compound pollution, photosynthesis, ozone, aerosol, sun leaf, shade leaf