Nanoparticle formation by ozonolysis of inducible plant volatiles

[摘要] We present the first laboratory experiments of aerosol formationfrom oxidation of volatile organic species emitted by livingplants, a process which for half a century has been known to takeplace in the atmosphere. We have treated white cabbage plants withmethyl jasmonate in order to induce the production of monoterpenesand certain less-volatile sesqui- and homoterpenes. Ozone wasintroduced into the growth chamber in which the plants wereplaced, and the subsequent aerosol formation and growth ofaerosols were monitored by measuring the particle sizedistributions continuously during the experiments. Ourobservations show similar particle formation rates as in theatmosphere but much higher growth rates. The results indicate thatthe concentrations of nonvolatile oxidation products of plantreleased precursors needed to induce the nucleation are roughly anorder-of-magnitude higher than their concentrations duringatmospheric nucleation events. Our results therefore suggest thatif oxidized organics are involvedin atmospheric nucleation events, their role is to participatein the growth of pre-existing molecular clusters rather than to formsuch clusters through homogeneous or ion-induced nucleation.

[学科分类] 大气科学