The distribution and circulation of 8 nutrient element contents and accumulation in the l0a artificial Cercidiphyllum japonicum community were studied. The results indicate:( 1 )The order of average content of elements in organs is Ca ＞ N ＞ Al ＞ K ＞ Mg ＞ P ＞ Fe ＞ Mn. (2) The order of different organs for element accumulation is roots ＞ leaves ＞ stems without barks ＞ barks ＞ branches, and the order of elements accumulation is Ca ＞ N ＞ K ＞ Al ＞ Mg ＞ P ＞ Fe ＞ Mn. (3) The amount of uptake, retention and return of 8 elements in the community is 729.82 kg· hm- 2 a-1、 206.72 kg· hm- 2 a- 1 and 523.10 kg· hm-2a-1, respectively. (4)51.2 % of total return for K is returned through rainfall leaching, 55.7 %～96.5% of the rests through litter. However,41.3% of total return for Fe and 44.3% for Al is still returned through dead roots,respectively. (5) Utilization coefficient, ratio of return to uptake, circulation period were 0.23～0.54、0.57～0.82 and 2.26 ～7.63. Meanwhile, the calculating method of nutrient elements returning through leaching was amended, and the uptake coefficient( annual element uptake/annual available element in soil), accumulation coefficient( annual element accumulation/ annual available element in soil)and return coefficient(annual element retum/annual available element in soil)were put forward. Finally, the calculating method of element circulation for deciduous forest was discussed.%研究了10年生连香树人工群落8种营养元素的含量、积累分配和循环。主要结论是：(1)连香树营养器官中各种元素的平均含量顺序为Ca＞N＞Al＞K＞Mg＞P＞Fe＞Mn。(2)元素量在各营养器官的分配顺序为根＞叶＞去皮干＞皮＞枝，各元素含量顺序为Ca＞N＞K＞Al＞Mg＞P＞Fe＞Mn。(3)连香树群落8种元素的吸收量、存留量和归还量分别是729.82 kg·hm-2a-1、206.72kg·hm-2a-1和523.10kg·hm-2a-1。(4)51.2％的归还总K量靠降水淋溶归还，其余元素总归还量的55.7％～96.5％靠凋落物归还。Fe、Al归还量的41.3％和44.3％通过死根归还。(5)8种元素的利用系数、归还比和周转期分别为0.23～0.54、0.57～0.82和2.26～7.63。文中改进了降水淋溶归还的算法，提出了群落归还系数、积累系数和吸收系数，讨论了落叶树种元素生物循环的算法。
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