Hollinger D Y
Forestry Research Centre, Forest Research Institute, P.O. Box 31-011, Christchurch, New Zealand.
Tree Physiol. 1987 Sep;3(3):193-202. doi: 10.1093/treephys/3.3.193.
Photosynthetic rates of 13-month-old Pinus radiata D. Don, Nothofagus fusca (Hook f.) Ørst. and Pseudotsuga menziesii (Mirb.) Franco seedlings grown and measured at elevated atmospheric concentrations of CO(2) (620 microl l(-1)) were 32 to 55% greater than those of seedlings grown and measured at ambient (310 microl l(-1)) concentrations of CO(2). Seedlings grown in ambient and elevated concentrations of CO(2) had similar rates of photosynthesis when measured at ~620 microl l(-1) CO(2), but when measured at ~310 microl l(-1) CO(2), the P. radiata and N. fusca seedlings which were grown at elevated CO(2) had lower rates of photosynthesis than the seedlings grown at an ambient concentration of CO(2). Stomatal conductances in general were lower when measured at ~620 microl l(-1) CO(2) than at ~310 microl l(-1) CO(2). Stomatal conductances declined in all species grown at both CO(2) concentrations when the leaf-air water vapor concentration gradient (DeltaW) was increased from 10 to 20 mmol H(2)O mol(-1) air. The percent enhancement in photosynthesis for P. radiata and P. menziesii at elevated CO(2) was greater at 20 mmol than at 10 mmol DeltaW, suggesting that elevated CO(2) may moderate the effects of atmospheric water stress. Dry matter allocation patterns were not significantly different for plants grown in ambient or high CO(2) air.
在大气二氧化碳浓度升高（约620微升/升）条件下生长并测量的13月龄辐射松、黑桫椤和花旗松幼苗的光合速率，比在环境二氧化碳浓度（约310微升/升）下生长并测量的幼苗高32%至55%。当在约620微升/升二氧化碳浓度下测量时，在环境二氧化碳浓度和升高的二氧化碳浓度下生长的幼苗具有相似的光合速率，但当在约310微升/升二氧化碳浓度下测量时，在升高的二氧化碳浓度下生长的辐射松和黑桫椤幼苗的光合速率低于在环境二氧化碳浓度下生长的幼苗。一般来说，在约620微升/升二氧化碳浓度下测量的气孔导度低于在约310微升/升二氧化碳浓度下测量的气孔导度。当叶-气水汽浓度梯度（ΔW）从10毫摩尔水/摩尔空气增加到20毫摩尔水/摩尔空气时，在两种二氧化碳浓度下生长的所有物种的气孔导度均下降。在升高的二氧化碳浓度下，辐射松和花旗松在20毫摩尔ΔW时的光合增强百分比高于10毫摩尔ΔW时，这表明升高的二氧化碳可能会缓解大气水分胁迫的影响。在环境空气或高二氧化碳空气中生长的植物的干物质分配模式没有显著差异。
