肉桂人工林叶片营养元素季节累积特点及其相互关系

Seasonal accumulation features of nutrient elements and their relationship in leaves of Cinnamomum cassia plantation

研究了不同林龄(3 a和6 a)肉桂人工林叶片5种营养元素(N,P,K,Ca和Mg)含量、季节变化动态及营养元素之间的相互作用关系。结果表明,不同林龄肉桂林叶片营养元素含量均为N>K>Ca>Mg>P,不同季节间营养元素的变异系数以Ca为最大,其次是Mg和K,然后是N,最小是P;不同林龄肉桂林叶片营养元素的季节变化规律相似,N以生长初期(3月中旬)最高,生长末期(12月中旬)最低;P和K以生长初期最低或较低,第一个生长高峰期(6月中旬)或第二个生长高峰期(9月中旬)最高或较高;Ca以第一个生长高峰期最低,生长末期最高或较高;Mg以生长初期最低,生长末期最高。肉桂植株P和K代谢之间呈正相关关系,P与Ca之间则存在显著的颉颃作用。

The dynamic properties of five nutrient elements （N, P, K, Ca and Mg） and the interaction between various nutrient in leaves of Cinnamomun cassia plantation of 3 and 6 year-stand age were studied. The results showed that the concentration of five elements in leaves of Cinnamomun cassia were in the order of N 〉K〉Ca〉Mg〉P, and the coefficient seasonally variability of Ca concentration was the biggest, followed by Mg and K, Mg and P were the smallest in leaves of Cinnamomun cassia. There were similar seasonal changes of nutrient elements concentration in leaves of Cinnamomun cassia plantation of 3 and 6 year-stand age, N was highest during bud flush （mid- March ）, and lowest in pre-dormancy （mid-December）. P and K was lowest or lower during bud flush, and higher or highest during the first fast growing season （mid-June） or the second fast growing season （mid-September）. Ca was lowest during the first fast growing season, and highest during predormancy. Mg was lowest during bud flush, and highest during pre-dormancy. There was a significantly positive interaction between P and K in Cinnamomun cassia plantation, but significant antagonism between P and Ca.