研究了广西高峰林场11年生(近熟林)马占相思人工林10种营养元素生物循环的特点。结果表明:(1)马占相思不同器官营养元素含量以树叶(叶状柄)为最高,树干最低;各器官中大量营养元素含量以N最高,其次是Ca或K,然后是Mg,P最低;微量元素含量则以Mn和Fe最高,其次是Zn和B,Cu最低;(2)林分营养元素贮存量为2609.28kg/hm^2,乔木层、灌木层、草本层和凋落物层分别占83.95%、4.43%、1.71%和9.91%,林木中不同器官营养元素贮存量排序为干材〉树枝〉树根〉干皮〉树叶.(3)林分年吸收量、归还量、存留量分别为388.47、195.51和192.96kg/(hm^2·a),10种元素的循环系数为0.39~0.78,循环速率依次为Mn〉Zn〉Mg〉P〉Ca〉Fe〉N〉Cu〉K〉B。
The biological cycle of 10 nutrient elements in the ll-year-old Acacia mangium plantation (near-mature) was studied in Gaofeng forest farm of Guangxi. The results were as follow: (1) The nutrient contents of Acacia mangiurn stand were different in different organs, highest in the leaves (phyllode) and lowest in the stems. The content of N was the highest, K and Ca the second, Mg and P were the lowest in macro-elements, while Mn and Fe were the highest, B and Zn the second, and Cu was lowest in micro-elements. (2) The total accumulation of 10 elements in the plantation was 2 609.28 kg/hm^2 , the nutrient elements accumulations of tree, bush, herb and litter were 83.95%, 4.43%, 1.71% and 9. 910%, respectively. The order of the nutrient accumulation in the different parts of the tree was stem〉branch〉root〉bark〉leaf. (3) The amount of uptake, retention and return of 10 elements in the plantation were 388.47 kg/ (hm^2·a), 195.51 kg/ (hm^2·a) and 192.96 kg/ (hm^2·a), respectively. The cycling coefficient was 0. 39-0.78,and the cycling speed was: Mn〉Zn〉Mg〉P〉Ca〉Fe〉N〉Cu〉K〉B.