宝天曼自然保护区锐齿栎林生态系统营养元素循环  

Study on element cycle of Quercus acutidentata forest ecosystem in Baotianman Natural Reserve

作　　者：刘玉萃[1] 吴明作[1] 郭宗民[1] 蒋有绪[2] 刘世荣[2] 

机构地区：[1]河南农业大学,郑州450002 [2]中国林科院森林生态环境与保护研究所,北京100091

出　　处：《生态学报》2003年第8期1488-1497,共10页Acta Ecologica Sinica

基　　金：国家林业局"八五"攻关课题资助项目 (编号 93 -0 8-0 60 2 )~~

摘　　要：对河南内乡宝天曼自然保护区内 35年生的天然次生锐齿栎林生态系统的营养元素循环进行研究 ,结果表明 :所测定系统中的 N、P、K、Ca、Mg、Fe、Na、Mn、Zn、Cu1 0种营养元素积累总量为 1 0 387.894kg·hm- 2 ,土壤库贮量 8880 .70 9kg·hm- 2 ,占 85 .49% ;植物体贮量 1 5 0 7.1 82 kg·hm- 2 ,占 1 4.5 1 % ,其中活植物体占 90 .5 6% ,凋落物占 9.44%。系统中 1 0种营养元素年吸收量 2 0 7.5 4 5 kg· hm- 2 ,年存留量1 0 5 .2 85 kg· hm- 2 ,年归还量 1 0 1 .65 1 kg·hm- 2 ,年积累速率为 77.8986kg·hm- 2 ;年归还量占年吸收量48.98% ,表明系统中营养元素的循环处于良好的平衡状态。 1 0种营养元素的平均利用系数为 0 .1 85 ,平均周转期为 9.98a。其中 P、N、Mg、Na、Mn的周转期较短为 4～ 8a,K、Ca、Fe、Cu周转期较长为 1 0～ 1 6a,Zn的周转期最长为 1 7.4a。This paper studied the element cycle of a 35-year-old %Quercus acutidentata% (Fagaceae) forest in Baotianman Natural Reserve, Neixiang county, He'nan Province. The forest is a secondary vegetation type in the northern deciduous forest region. Investigations were carried out in a 20×20 m2 plot in which trees were measured and ranked according to Kraft (1884) method during 1993~1995. The stand biomass was determined and the element contents of N, P, K, Ca, Mg, Fe, Na, Mn, Cu and Zn were analyzed in trees, shrubs, herbs, litters, soils, as well as in different tree organs.;The results showed that there were element allocation differences in the different tree organs. Ca, Na, N, K and Mg concentration were the highest in leaves, barks and roots, but the lowest in stems. However, P was relatively higher in branches, roots and leaves, while Fe was higher in roots. The average element content in the layer of shrubs and herbs was higher than that in the layer of trees. Nevertheless, tree layer accumulated the largest amount of elements for the highest biomass. The concentration of Ca, N, P and Fe was relatively higher in branches, leaves and barks than in stems. ;The element accumulation in the tree layer aboveground was obviously higher than that underground with the exception of Fe and Zn. The element accumulation orders was Ca> K> Na> N> Mg> P> Mn> Fe> Zn> Cu in the tree layer and was stem> root> bark> branch> leaf> fruit in the different tree organs. In the shrub layer, N, Ca, Na and K contents were relatively higher than the other elements. Herb layer showed a lower elemental accumulation. The total element accumulation in the litter was 143.9591kg·hm -2, accounting for only 10.76% of that in the tree layer. Those elements such as Ca, Na, N and K were highly accumulated in soils, plants and litters. The total amount of the 10 elements in soil was 8880.709 t·hm -2, but only 1688.451 t·hm -2 in the surface layer (0~18cm). It showed that the element cycle in the forest ecosystems was affected not only by the pl

关 键 词：锐齿栎林 营养元素循环 生态系统 宝天曼自然保护区 

分 类 号：S718[农业科学—林学]