榄仁树的生理和生物学特性

为了解榄仁树(Terminalia catappa)的生理生态特性,对西沙群岛永兴岛上自然生长的榄仁树的叶片形态、生理特征、营养元素含量以及根际土壤特征进行了研究。结果表明,榄仁树具有比叶面积低、叶片厚、气孔密度小等形态特征。叶绿素a/b为2.25∶1,低于理论值3∶1。叶片的SOD和POD活性较低,脯氨酸和ABA含量较高。植物体内养分含量较高,适生土壤养分含量低。这说明榄仁树叶片的吸收利用光能能力较强,保水能力较好,有较强的抗干旱和抗逆能力,适生于贫瘠的土壤并保持较高的叶片营养。因此,榄仁树是一种能够适应高温、干旱、贫瘠等恶劣生境条件的树种,可作为热带珊瑚岛植被恢复的工具种和园林绿化树种。

Physiological and Biological Characteristics of Terminalia catappa

In order to understand the eco-physiological characters of Terminalia catappa, its leaf morphology, physiology, nutrient element contents and the rhizosphere soil characteristics were studied grown in Yongxing Island, Xisha Islands. The results showed that T. catappa had low specific leaf area, thick leaf thickness and low stomatal density. The chlorophyll a/b (2.25:1) was lower than theoretic value (3:1). The SOD and POD activities in leaves were low, but proline and abscisic acid contents were high. The nutrient element contents in leaves were high, but the suitable soil nutrient content was low. It indicated that the leaves of T. catappa had high light energy absorptivity, good water holding capacity, and high drought tolerance, thus it was suitable to grow in poor soil conditions and maintain high leaf nutrition levels. Overall, T. catappa can tolerate high temperature, drought and barren soil and can be used as a tool and landscaping species for vegetation restoration on tropical coral island.