Department of Plant and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Göteborg, Sweden.
Environ Pollut. 2011 Oct;159(10):2350-4. doi: 10.1016/j.envpol.2011.06.001. Epub 2011 Jul 5.
With rising concentrations of both atmospheric carbon dioxide (CO(2)) and tropospheric ozone (O(3)), it is important to better understand the interacting effects of these two trace gases on plant physiology affecting land-atmosphere gas exchange. We investigated the effect of growth under elevated CO(2) and O(3), singly and in combination, on the primary short-term stomatal response to CO(2) concentration in paper birch at the Aspen FACE experiment. Leaves from trees grown in elevated CO(2) and/or O(3) exhibited weaker short-term responses of stomatal conductance to both an increase and a decrease in CO(2) concentration from current ambient level. The impairement of the stomatal CO(2) response by O(3) most likely developed progressively over the growing season as assessed by sap flux measurements. Our results suggest that expectations of plant water-savings and reduced stomatal air pollution uptake under rising atmospheric CO(2) may not hold for northern hardwood forests under concurrently rising tropospheric O(3).
随着大气二氧化碳（CO2）和对流层臭氧（O3）浓度的上升，更好地了解这两种痕量气体对影响陆地-大气气体交换的植物生理学的相互作用效应变得尤为重要。我们研究了在大气 CO2 和 O3 浓度升高条件下，单独和联合生长对在 Aspen FACE 实验中桦木初始短期气孔对 CO2 浓度响应的影响。在大气 CO2 和/或 O3 浓度升高条件下生长的叶片，其气孔导度对 CO2 浓度从当前环境水平升高和降低的短期响应均较弱。通过 sap flux 测量评估，O3 对气孔 CO2 响应的损害很可能随着生长季节的推移而逐渐发展。我们的研究结果表明，对于同时大气 O3 浓度升高的北方硬木林，对于植物在大气 CO2 升高条件下节约水分和减少气孔空气污染吸收的预期可能并不成立。
