气候驱动下大豆叶片气孔O3吸收通量的变化及时空演变

摘要

通过开顶式气室(OTC),分析了OTC内主要气象因子(温度、光合有效辐射、水汽压差等)和大豆叶片气孔导度的变化特征.引进Javis气孔导度模型,进行参数本地化,同时根据O3吸收通量模型,研究了大豆叶片气孔O3吸收通量的变化,并计算了江苏省各市大豆气孔导度和O3吸收通量的变化.结果表明:①利用修订后的Javis气孔导度模型对大豆叶片气孔导度的模拟效果较好,模型解释了实测气孔导度82%的变异性.②CK、100nL/L和150nL/L O3浓度处理下大豆在整个O3熏期的累积吸收通量分别为14.46mmolO3/m2、15.86mmolO3/m2和16.69mmolO3/m2.③江苏地区O3浓度在大豆生长季期间呈现逐渐增加的趋势,其叶片平均气孔导度大小表现为前期>中期>后期的变化特点,在前期时段气孔O3累积吸收通量最多.%The Open-Top Chamber is used to make field experiment, it is expected to obtain the data including temperature, light radiation, water vapor pressure difference and stomatal conductance by continuous observation. Stomatal conductance model is used and parameterized, combined with the ozone absorption flux model, we studied the characteristics of stomatal ozone fluxesof soybean. Meanwhile, the variations of stomatal conductance and ozone absorption fluxes of soybean were calculatedin Jiangsu province. Results show that the parameterized Jarvis model is applicable tothe simulation of stomatal conductance in soybean. Approximately 82% 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, 100nL/L, 150nL/L was 14.46mmol/m2, 15.86mmol/m2, and 16.69mmol/m2, respectively. The ozone concentration gradually increased from early period to late period during the period of soybean growth in Jiangsu. Average stomatal conductance is the early stage>the middle stage > the later stage. Ozone cumulative absorption flux is the most during the early stage. This study will provide a reference for the future study of effects of ozone on crops, and can also be used as the theory basis for the government and international organizations formulate policies, laws and regulations.