广东省茂名油页岩废渣堆放场主要树种的叶片气孔气体交换

Stomatal Gas Exchange in Leaves of Major Trees on the Oil Shale Residue in Maoming, Guangdong

摘要:

在茂名油页岩废渣堆放场主要绿化树种中选取青梅(Vaticamangachapoi)、海南红豆(Ormosiapinnata)和非洲桃花心木(Khayasenegalensis)3种植物进行测定。结果表明,3种植物的净光合速率的大小有明显的差异,从大到小的顺序是非洲桃花心木>海南红豆>青梅,海南红豆和非洲桃花心木的光合速率日变化幅度较大,而青梅的则相对较小；气孔导度从大到小依次为非洲桃花心木>海南红豆>青梅；三者净光合速率的差异与气孔导度有关。非洲桃花心木虽然具有较高的净光合速率,但由于其气孔导度较高,散失的水分较多,其内在水分利用效率比海南红豆低。青梅下午的内在水分利用效率比上午高得多,是由于其气孔导度下午比上午明显降低而限制了蒸腾失水的缘故。在油页岩废渣场,海南红豆和非洲桃花心木比青梅具有较强的生态适应性。

Abstract:

Based on a survey of the major trees grown on oil shale residue in Maoming, Guangdong, three species, (Vatica mangachapoi, Ormosia pinnata, and Khaya senegalensis) were chosen from 35 tree species for further study of their adaptation to such environment. The results showed that the net photosynthetic rates of the 3 species were significantly different, with a ranking of K. senegalensis> O. pinnata > V. inangachapoi. Diurnal variations of net photosynthetic rate in K. senegatensis and O. pinnata were great while that in V. mangachapoi was less. The ranking of their stomatal conductances was K. senegalensis > O. pinnata > V. mangachapoi. The difference in net photosynthetic rate among the three trees was related to the stomatal conductance. Though the net photosynthetic rate in K. senegalensis was higher, its intrinsic water use efficiency was lower than that in O. pinnata due to more water loss. The intrinsic water use efficiency of V. mangachapoi was much higher in the afternoon because of the lower stomatal conductance. The results indicate that K. senegalensis and O. pinnata might be more adaptable to the special environment.