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对广西南丹山口林场秃杉人工林的N、P、K、Ca和Mg等5种营养元素含量、积累和分配及其随林分年龄的变化趋势进行了研究。结果表明,不同组分营养元素含量大小次序为树叶>干皮>树枝>树根>干材;林木各组分营养元素含量以N,Ca或K最高,其次是P,Mg最低。8、14和28年生林分营养元素积累总量分别为574.79、833.21和1 214.11kg.hm-2,其中乔木层营养元素积累量依次占92.87%、86.74%和85.88%,林下植被层依次占2.02%、2.99%和4.62%,地表现存凋落物层依次占5.11%、10.27%和9.50%;乔木层均以N或Ca积累量最多,Mg最少;秃杉人工林不同组分营养元素积累量的分配随林分年龄的增长发生变化,由8年生和14年生以树叶和树枝为主,逐渐转移到28年生以干材和树皮为主。3个林分年龄秃杉林每积累1 t干物质需要5种营养元素总量分别为8.97、6.40和4.21kg,其中对N或Ca的需求量最大,Mg最少。
The content, accumulation and distribution of N, P, K, Ca and Mg in the plantation of Taiwania flousiana Forest in Nandan Pass, Guangxi Province, were studied. The results showed that the order of nutrient content of different components was leaf> dry skin> branch> tree root> dry material. The content of nutrient elements in each component of the forest was the highest in N, Ca or K, followed by P and Mg. The total amount of nutrient elements in 8, 14 and 28 year old stands were 574.79, 833.21 and 1 214.11kg.hm-2, respectively, in which the nutrient accumulation in the tree layers was 92.87%, 86.74% and 85.88% Accounting for 2.02%, 2.99% and 4.62% respectively. The litter layer on the ground surface accounted for 5.11%, 10.27% and 9.50% in turn. The arbor layer accumulated most N and Ca and the least Mg. The distribution of the amount changes with the growth of the stand age, mainly from the 8-year-old and 14-year-old leaves and branches, and gradually transferred to the 28-year-old stems and bark-based. The total amount of five kinds of nutrients required for the accumulation of 1 t of dry matter in the three stands of Taiwania flousiana forests was 8.97, 6.40 and 4.21 kg, respectively, of which the demand for N or Ca was the largest and the Mg was the least.