在陕西省桥山林区 3块油松人工林样地中 ,对油松人工林生态系统各组分中N、P、K、Ca和Mg等 5种营养元素的含量、分配格局、积累规律以及它们与密度间的关系进行了研究 .结果表明 ,油松人工林不同器官中营养元素含量排序为树叶 >树枝 >树根 >树皮 >干材 ;在 2 6年生油松人工林现存量中 ,N、P、K、Ca、Mg总量分别为 2 14 44、2 2 91、15 8 88、167 3 6和 2 9 42kg·hm-2 ;乔木层、灌木层、草本层和死地被物层养分贮量分别为498 98、3 3 2、7 3 1和 83 40kg·hm-2 ;油松人工林N、P、K、Ca和Mg的富集系数分别为 3 98、4 2 8、5 69、1 0 8和 4 0 1;每生产 1t有机物质需要这 5种元素约 8 43～ 9 0 9kg·hm-2 ·a-1;乔木层中营养元素积累量为 2 88 2 6～ 60 6 0 7kg·hm-2 ,其中干材营养元素积累量约占乔木层的 14 1%～ 16 8% . The content, distribution pattern and accumulation of N, P, K, Ca and Mg in the components of Pinus tabulaeformis plantation ecosystem in three Pinus tabulaeformis plantations in Qiaoshan, Shaanxi Province, China The results showed that the order of nutrient elements in different organs of Pinus tabulaeformis plantation was leaf> tree branch> tree root> bark> dry material; in the existing stock of 26 year old Pinus tabulaeformis plantation, The total amount of N, P, K, Ca and Mg were 2 14, 44 2, 21 8, 15 8 88, 167 6 and 29 42 kg · hm -2, respectively. The contents of arbors, shrubs, Nutrient storage were 498 98,3 3 2,7 3 1 and 83 40kg · hm-2 respectively; the enrichment coefficients of N, P, K, Ca and Mg in Pinus tabulaeformis plantation were respectively 3 98,4 2 8,5 69,1 0 8 and 4 0 1, and the production of 1 ton of organic matter required about 8 43 ~ 9 0 9 kg · hm-2 · a-1 for these 5 elements; and the accumulation of nutrient elements in the arbor layer was 2 88 2 6 ~ 60 6 0 7kg · hm-2, of which the dry wood nutrient element accumulation of about 14 1% ~ 16 8%.