海南岛热带云雾林植物枝条和叶片氮、磷、可溶性糖分配规律

Allocation of nitrogen,phosphorus and soluble sugar in twigs and leaves of tropical cloud forests in Hainan Island

研究热带云雾林植物N、P及可溶性糖分配规律,对了解植物生长及对环境的适应性有重要意义。通过测定海南岛3个林区热带云雾林282种植物的枝条与叶片中N、P和可溶性糖含量,比较枝条、叶片中各个养分的差异,分析养分间的关联性。结果表明,植物叶片N、P和可溶性糖含量均显著高于枝条,其中枝条和叶片可溶性糖含量分别为(15.06±9.4)和(32.14±19.57)g·kg^(-1),氮含量分别为(3.48±1.02)和(9.51±5.26)g·kg^(-1),磷含量分别为(0.23±0.15)和(0.56±0.44)g·kg^(-1)。黎母山植物枝条、叶片的N和P含量最高,霸王岭植物最低;霸王岭植物枝条可溶性糖含量显著高于黎母山和尖峰岭,而霸王岭植物叶片可溶性糖含量显著低于黎母山和尖峰岭。在植物枝条、叶片中,N与P含量均呈显著正相关,而可溶性糖与P含量无显著相关性;在枝条与叶片之间,可溶性糖含量无显著相关,而N含量和P含量显著正相关。此外,P元素是海南岛热带云雾林植物生长及种群发育的主要限制性因子。

Studies on allocation of nitrogen（ N）,phosphorus（ P） and soluble sugar in plants of tropical cloud forest play an important role in understanding the growth and adaptation of plants to the environment. We measured the contents of N,P and soluble sugar in the twigs and leaves from the 282 species of tropical cloud forests in three sites（ i.e.,Bawangling Mountain（ BWL）,Jianfengling Mountain（ JFL） and Limushan Mountain（ LMS）） of Hainan Island,aiming to clarify the correlations of N,P,and soluble sugar in different vegetative organs. The results showed that the contents of N,P and soluble sugar in leaves were significantly higher than those in twigs.In twigs and leaves,the contents of soluble sugar were（ 15. 06 ± 9. 4） and（ 32. 14 ± 19. 57） g·kg^-1,the contents of N were（ 3.48±1.02） and（ 9.51±5.26） g·kg^-1,and the contents of P were（ 0.23±0.15） and（ 0.56±0.44） g·kg^-1,respectively. The contents of N and P in the leaves and stems were the highest in LMS and the lowest in BWL. The content of soluble sugar in the twigs of BWL was significantly higher than that in LMS and JFL,whereas the content of soluble sugar in leaves was significantly lower than that of LMS and JFL. In twigs and leaves,there were significantly positive correlations between N and P contents,while soluble sugar contents were not significantly related to P contents. Moreover,N and P contents in twigs were significantly positive correlated with that in leaves,while there was no significant correlation in soluble sugar content between twigs and leaves. In addition,we found that P was a main limiting factor for plant growth and population development in the tropical cloud forests of Hainan Island.