桐花树和海桑次生木质部的生态解剖

THE ECOLOGICAL SECONDARY XYLEM ANATOMY OF THE MANGROVE AEGICERAS CORNICULATUM AND SONNERATIA CASEOLARIS

对紫金牛科 (Myrsinaceae)的桐花树 (Aegicerascorniculatum)和海桑科 (Sonneratiaceae)的海桑 (Son neratiacaseolaris)的次生木质部的组织结构和数量特征进行了研究 ;并讨论了桐花树和海桑的木材结构与环境关系 ;它们的导管直径小、导管数量多、导管分布频率高 ,是对海滨盐渍环境的适应 ,保证水分在植物体内运输的安全性。桐花树和海桑的纤维壁厚度 (W )与纤维腔宽度 (L)的比值 (2W /L)分别为 0 6 7和 0 4 5 ,均小于 1 ,从木纤维 2W /L <1的角度看 。

This paper deals with the morphological and quantitative characters of secondary xylem of Aegiceras corniculatum and Sonneratia caseolaris . The relation between the structure of wood and the environmental influences has also been discussed.The features of small vessel diameter,many vessel numbers and high vessel frequency ensure the safety for water transportation inside plant.The ratios (2W/L), namely thickness of fiber wall (W) and width of fiber cavity (L), of both Aegiceras corniculatum (0.67)and Sonneratia caseolaris(0.45) are less than 1,demonstrating their timbers are the good raw materials for papers making.