急性O_(3)胁迫下米槠类异戊二烯释放及其对O_(3)生成潜势的影响  

Isoprenoid release from Castanopsis carlesii under acute O_(3) stress and its effect on ozone formation poten⁃tial

作　　者：廖露露 张哿烨 张峻川 陈红梅 李强 易志刚[1] LIAO Lulu;ZHANG Geye;ZHANG Junchuan;CHEN Hongmei;LI Qiang;YI Zhigang(Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation,College of Resources and Environment,Fujian Agricul-ture and Forest University,Fuzhou 350002,China)

机构地区：[1]福建农林大学资源与环境学院,土壤环境健康与调控福建省重点实验室,福州350002

出　　处：《生态学杂志》2024年第11期3266-3274,共9页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41877326);福建农林大学科技创新专项基金项目(KFB23115)资助。

摘　　要：类异戊二烯(主要包括异戊二烯ISO和单萜烯MTs)是植物源挥发性有机化合物(BVOCs)中一类最重要的化合物,在大气环境中有重要作用。本研究以2年生米槠(Castanopsis carlesii)为对象,设置O_(3)-CK(大气背景浓度)、O_(3)-250(O_(3)浓度250 ppb)、O_(3)-500(O_(3)浓度500 ppb)3个处理,对米槠进行8 h、16 h的急性O_(3)胁迫,研究急性O_(3)胁迫下米槠BVOCs释放对O_(3)生成潜势(ozone formation potential,OFP)及生理指标的影响。结果表明:急性O_(3)胁迫8 h后,随O_(3)浓度升高,MTs释放速率高于对照组,在O_(3)-250处理下达到峰值(52.72±35.72 pmol·m^(-2)·s^(-1)),ISO释放速率低于对照组,在O_(3)-500处理下降至最低(0.70±0.27 pmol·m^(-2)·s^(-1))。MTs组分中γ-松油烯、柠檬烯含量显著增加,α-蒎烯、柠檬烯对OFP贡献较大。急性O_(3)胁迫16 h后,随O_(3)浓度升高,MTs释放速率高于对照组,ISO释放速率无显著变化。3-蒈烯含量显著增加,α-蒎烯、柠檬烯、3-蒈烯对OFP贡献较大。总体上,O_(3)胁迫导致MTs合成酶和ISO合成酶显著降低,随胁迫时间延长,米槠光合速率、MTs和ISO释放速率均降低。急性O_(3)胁迫促进MTs排放,抑制ISO排放,进而整体促进OFP。本研究可为今后近地表O_(3)浓度增加背景下植物BVOCs释放对O_(3)的响应以及BVOCs对O_(3)形成的机理研究提供理论依据。Isoprenoids,mainly including isoprene and monoterpenes,are among the most important biogenic vola⁃tile organic compounds(BVOCs)from plants and play an important role in atmospheric environments.In this study,Castanopsis carlesii was treated with O_(3)⁃CK(ambient O_(3) concentration),O_(3)⁃250(O_(3) concentration 250 ppb)and O_(3)⁃500(O_(3) concentration 500 ppb)for acute O_(3) stress of 8 h and 16 h.We investigated the effects of acute O_(3) stress on BVOc emissions from C.carlesii and the associated physiological parameters,as well as the contribu⁃tion of BVOC emissions to ozone formation potential(OFP).The results showed that after 8 h acute O_(3) stress,the release rate of monoterpene was higher under the treatment with O_(3) stress than that of the control group,and reached a peak at O_(3)⁃250 treatment(52.72±35.72 pmol·m^(-2)·s^(-1)),while the release rate of isoprene was lower than that of the control group.At the O_(3)⁃250 treatment,it decreased to the lowest(0.70±0.27 pmol·m^(-2)·s^(-1)).The contents ofγ⁃terpinene and limonene increased significantly,andα⁃pinene and limonene contributed more to OFP.After 16 h acute O_(3) stress,the release rate of monoterpene under O_(3) stress was higher than that of the control group,but the release rate of isoprene did not change.The content of 3⁃carene increased significantly,andα⁃pi⁃nene,limonene,3⁃carene contributed more to OFP.Monoterpene synthetase and isopentadiene synthetase de⁃creased significantly under O_(3) stress.Photosynthetic rate of C.carlesii and release rate of monoterpene and isopenta⁃diene decreased with increasing stress time.Acute O_(3) stress promoted monoterpene emission and inhibited isoprene emission,with a positive effect on OFP as a whole.This study can provide theoretical basis for future studies on the response of BVOC release to O_(3) under the trend of near⁃surface O_(3) concentration increase and the mechanism of BVOCs on O_(3) formation.

关 键 词：臭氧 异戊二烯 单萜烯 生物源挥发性有机化合物 臭氧生成潜势 

分 类 号：X515[环境科学与工程—环境工程]