黄土高原乡土树种光合作用及抗旱性研究

对黄土高原乡土树种油松、刺槐、侧柏、山杏、连翘、辽东栎、文冠果、丁香、臭柏、金银花等10个树种的光合作用和抗旱性指标进行了测定和比较。结果表明,丁香、侧柏和刺槐具有极强的利用太阳光的能力,耐荫性较差,金银花耐荫性最强。与侧柏和刺槐相比,油松的耐荫性较强。金银花、山杏、连翘、辽东栎、文冠果、丁香、臭柏、油松、侧柏、刺槐的耐荫性依次降低。另外,辽东栎、文冠果、臭柏和金银花对弱光的利用率较高,可以适应一定的较弱光照环境。丁香、刺槐和侧柏为典型的阳性树种,金银花为典型的阴性树种,辽东栎、文冠果、臭柏、油松、山杏和连翘既可以适应弱光条件,也可以在一定的强光照条件下生长。10个树种在脯氨酸、可溶性糖含量、电导率及水分特性上有差异,其抗旱机制各不相同,但它们都具有较强的抗旱能力,适宜黄土高原干旱的自然条件。

Photosynthesis and Drought Resistance of the Native Species in Loess Plateau

The photosynthesis and drought resistance of ten tree species were measured and compared each other in loess plateau,such as Pinus tabulaeformis,Robinia pseudoacacia,Platycladus orientalis,Prunus armeniaca,Forsythia suspensa,Querucus liaotungensis,Xanthoceras sobifolia,Syringa oblata,Sabina vulgaris and Lonicera japonica,It was found that P.orientalis,S.oblat and R.pseudoacacia had the higher capacity to absorb and utilize the sun light,and these were shade intolerant tree species.But L.japonica was a shade-tolerant one.For these main forestation tree species,P.tabulaeformis was better to tolerate the shade condition than R.pseudoacacia and P.orientalis.The order of shade-tolerance from higher to lower was L.japonica,P.armeniace,F.susoensa,Q.liaotungensis,X.sobifolia,S.oblata,S.vulgaris,P.tabulaeformis,R.pseudoacacia and P.orientalis.In addition,all of these three tree species,Q.liaotungensis,X.sobifolia,S.vulgaris and L.japonica could adapt to lower light intensity.But these six tree species,Q.liaotungensis,X.sobifolia,S.vulgaris,P.tabulaeformis,P.armeniace and F.susoensa,could grow better either shade condition or not.On the other hand,although these ten tree s(pecies had different mechanism of drought stress,they all had higher drought resistance and could suit to drought condition on loess plateau.