论文部分内容阅读
在鼎湖山南亚热带常绿阔叶林中，植物叶片营养元素含量为：Ｎ ０．９４６％一２．５３５％，Ｐ ０．０３０％—０．１２７％， Ｋ ０．６１４％—１．８３３％， Ｃａ ０．４４２％—１．９９５％， Ｍｇ ０．０２４％—０．１８８％。叶片各营养 养元素间相关性较差，仅Ｐ与Ｍｇ及Ｍｇ与Ｋ之间存在显著的线性相关。叶片Ｎ元素平均含量在各层 中的序列为：乔木Ⅲ＞乔木Ⅱ＞乔木Ⅰ＞灌木＞藤本＞草本；其它营养元素浓度随层次分配的规律 性不甚明显，但总趋势为乔木层植物略低于其它层植物。不同营养元素平均含量在各器官中的大小排列 顺序为：Ｎ叶＞皮＞枝＞根＞干；Ｐ叶＞枝＞根＞皮＞干；Ｋ叶＞枝＞皮＞根＞干；Ｃａ 皮＞叶＞枝＞根＞干； Ｍｇ叶＞根＞皮＞枝＞干。大部分植物在同一器官中各营养元素平均含 量序列为：叶、枝和根中均为Ｎ＞Ｃａ＞Ｋ＞Ｍｇ＞Ｐ；干Ｋ＞Ｃａ＞Ｎ＞Ｍｇ＞Ｐ；皮Ｃａ＞Ｎ＞Ｋ＞Ｍｇ＞Ｐ。 对元素含量分配格局分析表明，Ｐ和Ｍｇ很可能是限制南亚热带常绿阔叶林植物生产力的最重要营养元 素。
In the subtropical evergreen broad-leaved forest in Dinghushan Mountain, the content of nutrient elements in plant leaves is N 0.946% -2.535%, P 0.030% -0.127%, K 0.614% -1.833% Ca 0.442% -1.995%, Mg 0.024% -0.188%. There was a significant linear correlation between P and Mg and Mg and K in leaves. The average content of N elements in leaves in each layer was as follows: tree Ⅲ> tree Ⅱ> tree Ⅰ> shrub> vine> herb. The regularity of distribution of other nutrient elements with different levels was not obvious. Lower than other layers of plants. The order of the average content of different nutrients in different organs was as follows: N leaf> bark> branch> root> stem; P leaf> branch> root> bark> stem; K leaf> branch> bark> root> stem; > Leaf> branch> root> dry; Mg leaf> root> bark> branch> stem. The average contents of nutrients in most organs of the same plant were: N> Ca> K> Mg> P in leaves, branches and roots; dry K> Ca> N> Mg> P; > Mg> P. Analysis of the distribution of elemental contents indicated that P and Mg are most likely the most important nutrients that limit plant productivity in the subtropical evergreen broad-leaved forest in South China.