[Influencing Mechanism and Spatio-temporal Pattern of Stomatal Ozone Flux of Winter Wheat Under Ozone Pollution].

As one of the main atmospheric pollutants over surface layer,researches on the increasing surface ozone concentration and its impact on main crops have become the focus of every government and the public.In this paper,based on the observations in Nanjing using the main local cultivars in China's major winter wheat producing areas,it was expected to obtain the data including ozone concentration,meteorological data and stomatal conductance by continuous observation.Stomatal conductance model was used and parameterized,combined with flux model,we analyzed the characteristics of stomatal flux in winter wheat under ozone pollution.At the same time,the stomatal conductance and stomatal ozone absorption flux of winter wheat were simulated in Jiangsu Province.The main results were as follows:Elevated ozone concentration could reduce stomatal conductance of winter wheat leaf and stomatal conductance decreased with the increase of ozone concentration.According to the observational data through the experiment,based on the boundary line technology,stomatal conductance model was parameterized to simulate stomatal conductance of wheat leaves from environmental factors.Approximately 90%,77% and 83% variation of measured stomatal conductance could be explained by the stomatal conductance model.In the experiment,the total ozone absorption flux in ozone concentration of CK (53.67 nL·L),100nL·L,150nL·L was 6.42 mmol·m,12.27 mmol·m,13.90 mmol·m respectively.The ozone concentration gradually increased from early period to late period during the period of winter wheat growth in Jiangsu area.The average stomatal conductance followed the order of the middle stage >the later stage >the early stage.Winter wheat ozone cumulative absorption flux was the highest during the middle stage.