八角叶片营养元素的季节动态变化特征及其相关性

Seasonal dynamic characteristics and nutrient elements correlations in Illicium verum leaves

【目的】研究八角成熟叶片中N、P、K、Ca、Mg、Cu、Zn、Fe、Mn、B共10种元素含量的季节动态及其相关性,为八角科学施肥提供理论依据。【方法】以正常生长的15年生成熟八角林为调查对象,每隔60d左右采样1次,测定成熟叶片中营养元素含量,并分析八角营养元素的季节动态变化特征及其相互关系。【结果】八角成熟叶片中大、中量营养元素含量依次为N>K>Ca>Mg>P,微量元素含量依次为Mn>Fe>B>Zn>Cu;叶片中营养元素含量随季节变化出现规律性波动,大、中量元素波动较小,微量元素波动较大;P、Ca、Cu、Zn、B等营养元素随着生长消耗,在成熟叶片中含量下降。【结论】八角树叶片营养元素的季节动态变化具有一定规律,生长旺盛的季节,八角的新生梢叶和生殖器官对营养元素的消耗量急剧增多,导致某些元素在成熟叶片中含量下降,应在生长发育旺盛期之前提早施肥,同时应注意协调各种营养元素用量,以避免元素之间发生过度的拮抗作用。

【Objective】The seasonal dynamic characteristics and the correlations between N， P， K， Ca， Mg， Cu， Zn， Fe， Mn， and B elements in mature Illicium verum leaves were studied in order to provide theoretic foundation for achieving timely fertilizer application， suitable fertilizer type， and appropriate fertilization concentration in Illicium verum cultivation. 【Method】Using the normally grown 15-year old mature Illicium verum forest as investigation subject， samples were collected 1 time around every 60 days to determine the nutrient element content in mature leaves， analyze the seasonal dynamics characteristics， and evaluate the correlations between the elements. 【Result】Large and medium amounts of nutrient element contents in mature leaves of Illicium verum were arranged in the following order： N＞K＞Ca＞Mg＞P， while the content of trace elements were arranged in the following order： Mn＞Fe＞B＞Zn＞Cu. The nutrient element content in leaves fluctuated according to seasonal changes. For large and medium amounts of elements， the fluctuation was small， but in trace elements， the fluctuation was noticeable large. P， Ca， Cu， Zn， B， and other nutrient elements were consumed along with plant growth， which caused the element contents in mature leaves to decrease. 【Conclusion】There were certain seasonal dynamic changing rules of the nutrient element content in Illicium verum leaves. During the exuberant growth season， the elements consumption increased sharply due to the nutrient necessity in plant reproductive organs and new tip leaves， which lead to the decline of some nutrient element contents in mature leaves. Fertilization should be applied during early growth stages before the exuberant growth period， and at the same time， the amount of every nutrient elements should be coordinated in order to avoid excessive antagonistic actions between the elements.