The effects of current and future elevated O-3 concentrations (e[O-3]) were investigated by a meta-analysis for poplar, a widely distributed genus in the Northern Hemisphere with global economic importance. Current [O-3] has significantly reduced CO2 assimilation rate (P-n) by 33% and total biomass by 4% in comparison with low O-3 level (charcoal-filtered air, CF). Relative to CF, an increase in future [O-3] would further enhance the reduction in total biomass by 24%, plant height by 17% and plant leaf area by 19%. Isoprene emissions could decline by 34% under e[O-3], with feedback implications in reducing the formation of secondary air pollutants including O-3 . Reduced stomatal conductance and lower foliar area might increase runoff and freshwater availability in O-3 polluted areas. Higher cumulated O-3 exposure over a threshold of 40 ppb (AOT40) induced larger reductions in P-n, total biomass and isoprene emission. Relationships of light-saturated photosynthesis rates (A(sat)), total biomass and chlorophyll content with AOT40 using a global dataset are provided. These relationships are expected to improve O-3 risk assessment and also to support the inclusion of the effect of O-3 in models addressing plantation productivity and carbon sink capacity. (C) 2018 Elsevier B.V. All rights reserved.
1.Nanjing Univ Informat Sci & Technol, Sch Environm Sci & Technol, Collaborat Innovat Ctr Atmospher Environm & Equip, Nanjing 210044, Jiangsu, Peoples R China 2.Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Shuangqing Rd 18, Beijing 100085, Peoples R China 3.Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China 4.Fdn CEAM, C Charles R Darwin 14,Parque Tecnol, Valencia 46980, Spain
Recommended Citation:
Feng, Zhaozhong,Shang, Bo,Gao, Feng,et al. Current ambient and elevated ozone effects on poplar: A global meta-analysis and response relationships[J]. SCIENCE OF THE TOTAL ENVIRONMENT,2019-01-01,654:832-840