Evaluation of the function of woody plants for environmental control under elevated atmospheric CO_2

研究了CO_2浓度增加对木本植物CO_2和H_2O气体交换的影响。本文介绍了木本植物在CO_2环境和升高条件下的气体交换研究：(1)CO_2浓度和光照强度对幼树光合作用和蒸腾速率的影响，(2)CO_2升高条件下常绿乔木对水分胁迫的抑制作用，(3)CO_2升高对树木幼苗热平衡和蒸腾的影响，(4)CO_2浓度升高对气态大气污染物吸收率的测定方法(5)树木对大气中气态污染物吸收速率的季节变化；(6)co2浓度对木本植物对大气中气态污染物吸收速率的短期影响，不同树种气体交换速率差异较大。目前，蓝桉和马相思因其适合造林而受到人们的关注。随着CO_2浓度的增加，它们的CO_2吸收量增加，而蒸腾速率在这些条件下下降明显。虽然有可能通过使用这些树木，由于它们在水资源有限的地区对水的高效利用以及它们在这种条件下生长和茁壮成长的能力，可以提高水的利用系数，但也应该记住，它们的低蒸腾速率也会影响热环境。

This study investigated the changes in CO_2 and H_2O gas exchange of woody plants due to increases in CO_2 concentrations. This report contains information obtained from the study on gas exchange of woody plants in ambient and elevated CO_2 concentrations :(1) effects of CO_2 concentration and light intensity on photosynthesis and transpiration rate of young trees,(2) inhibition of water stress in evergreen trees under elevated CO_2 concentration,(3) effects of elevated CO_2 concentration on heat balance and transpiration of tree seedlings,(4) method for measurement of sorption rates of gaseous air pollutants by woody plants with a field chamber,(5) seasonal change in sorption rates of gaseous air pollutants by trees,(6) short term effects of CO_2 concentration on gaseous air pollutants sorption rates of woody plants,Depending on the species of tree, the gas exchange rate varied greatly. At present, Eucalyptus globulus and Acacia mangium are gaining attention due to their suitability for use in afforestation. As CO_2 concentration levels increased, their CO_2 uptake increased, however the decrease of the transpiration rate under these conditions was remarkable. Although it is possible that through the use of such trees the water usage coefficient can improve due to their highly efficient use of water in areas of limited water resources and their ability to grow and thrive under such conditions, it should also be remembered that their low transpiration rate will also influence the thermal environment.