海人树的生态生物学特性

Ecological and biological characteristics of Suriana maritima

海人树(Suriana maritima)是海人树科的一种滨海观赏植物,目前在中国仅分布于南海诸岛。该文以西沙群岛自然生长的海人树为研究对象,通过调查、采样,分析测定其茎杆及其叶片的形态解剖结构、叶片的抗氧化酶活性和抗逆渗透物质含量,以及叶片与生长土壤的营养元素含量等生态生物学特性。结果表明:(1)海人树的叶片小而厚,角质层明显,栅栏组织发达,气孔密度小(8.64 n·mm^(-2)),易于维持体内水分,能很好地适应干旱和高盐碱的环境;叶片的叶绿素含量低(0.76 mg·g^(-1)),总抗氧化能力高(589.50 U·g^(-1)),脯氨酸含量高(1123.64μg·g^(-1)),表明海人树光合利用效率高,抗氧化能力强。(2)海人树根际土壤的养分含量低,而叶片有机碳、氮、磷含量较高(分别为490.27、18.10、3.81 g·kg^(-1)),表明海人树的土壤养分利用效率高,对贫瘠的土壤具有良好的适应能力。综上表明,海人树对强光、干旱、高盐碱和土壤贫瘠的热带珊瑚岛环境具有良好的适应能力,可作为热带珊瑚岛植被恢复和园林绿化的工具种。该研究结果为其保护及开发利用提供了理论依据。

Suriana maritima is a coastal ornamental plant species distributing only on the South China Sea Islands in China,at present.In order to understand the ecological and biological characteristics of S.maritima,we investigated the morphological and anatomical structure of stem and leaf,the antioxidant enzyme activity and osmotic adjustments contents in leaf of S.maritima,and nutrient element contents in leaf and soil of S.maritima growing on the Paracel Islands,by field investigation and sampling for analysis.The results were as follows:(1)S.maritima had small and thick leaf,well-developed palisade tissue,and low stomatal density(8.64 n·mm^(-2)),which make it easy to maintain water in the body and suitable for drought and high saline-alkali environments.The chlorophyll content(0.76 mg·g^(-1))of the leaf was low,the total antioxidant capacity(589.50 U·g^(-1))and proline content(1123.64μg·g^(-1))were high,indicating that S.maritima had high photosynthetic utilization efficiency and strong antioxidant capacity.(2)Though the nutrient in natural growing soil was poor,the contents of organic carbon,nitrogen and phosphorus in leaf of S.maritima were relatively high(490.27,18.10,and 3.81 g·kg^(-1),respectively),indicating a high nutrient utilization efficiency and good adaptability of S.maritima to poor soil.In conclusion,S.maritima has a good adaptability to the environment of strong radiation,drought,high saline-alkali and poor soil on tropical coral islands,and can be used as a tool species for revegetation and landscaping on tropical coral islands.The results provide a theoretical basis for its protection,development and utilization.