Contents, accumulation and distribution of nutrient elements (N, P, K, Ca, Mg, Fe, Mn, Zn and Cu) in a 10-year-old Manglietia glauce plantation in Nanning, Guangxi were studied at fast growing stage based on field investigation and lab analysis. Results showed that the nutrient content in the leaves of M. glauce was the highest, followed by bark, branch, root, and trunk. Concentration of N was the highest, K or Ca ranked second, Mg and P were the lowest in macro-elements; while Mn and Fe were the highest, Zn ranked second, and Cu was lowest in micro-elements. The total accumulation of 9 elements in the plantation was 999.32 kg/hm2, of which the tree layer was 858.58 kg/hm2( accounting for 85.91 % ) , and litter layer was 140.48 kg/hm2( 14.06% ). The annual net accumulation of nutrient elements of M. glauca plantation was 85.83 kg/(hm2 · a) , and the sequence of the nutrient accumulation in different parts of the tree was stem>leaf> bark>root>branch. The net production of organic of forest per ton needs 8. 94 kg of macro-elements, and the nutrient utilization efficiency of M. glauce plantation was evidently higher than that of Pinus massoniana and Cunninghamia lanceo-lata plantations.%通过野外调查和实验室分析,研究了广西南宁市速生阶段(10年生)灰木莲人工林的9种营养元素(N、P、K、Ca、Mg、Fe、Mn、Zn和Cu)的质量分数、积累及其分配特征.结果表明:(1)灰木莲不同器官的营养元素质量分数大致为树叶＞树皮＞树枝＞树根＞树干；各器官大量元素质量分数大致以N最高,其次是Ca或K,Mg和P最低；微量元素质量分数则以Mn或Fe最高,Zn次之,Cu最低.(2)灰木莲人工林营养元素积累总量为999.32 kg/hm2,其中乔木层的营养元素积累量为858.58 kg/hm2,占林分营养元素积累总量的85.91％,凋落物层营养元素积累量为140.48 kg/hm2,占总积累量14.06％.(3)灰木莲人工林营养元素年净积累量为85.83 kg/(hm2·a),各器官营养元素年净积累量排列顺序为树干＞树叶＞树皮＞树根＞树枝.(4)灰木莲人工林每积累1t干物质需要5种大量元素8.94 kg,其营养元素利用效率明显高于马尾松和杉木人工林.
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