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在人工气候室和温室条件下,控制不同土壤干旱梯度,从光合作用、水分利用效率、叶绿素含量,以及叶绿素a荧光等方面研究了1～3年生油松、侧柏、栓皮栎、元宝枫,刺槐、白蜡、紫穗槐,沙棘和黄栌等9个树种的耐旱生产力.结果表明,供试树种的光合作用具有明显的日变化规律,在干旱胁迫条件下,随着水势的降低,净光合速率和叶绿素a/b值逐渐下降,水分利用效率、叶绿素总含量及叶绿素a荧光强度则是先增加而后才降低.
Under the conditions of artificial climate chamber and greenhouse, different soil drought gradients were controlled. The photosynthesis, water use efficiency, chlorophyll content and chlorophyll a fluorescence were used to study the effects of Pinus tabulaeformis, Platycladus orientalis, Quercus variabilis, Black locust, white locust, Amorpha fruticosa, Hippophae rhamnoides and Pterocarya stenoptera L. The results showed that the photosynthesis of the tested tree species had obvious diurnal variation pattern. Under drought stress, with the decrease of water potential, net photosynthesis The rate and the chlorophyll a / b value decreased gradually. The water use efficiency, total chlorophyll content and chlorophyll a fluorescence intensity increased first and then decreased.