长白山某些树种叶子的分解动态研究

 在长白山针阔叶混交林下，红松、蒙古栎、春榆、白桦、山杨、色木及紫椴叶分解至300天时，其重量损失百分数分别为24.2，37.6，30.8，44.47，50.6及55.6。在分解过程中，每种叶子的重量损失同该叶子的木质素、水溶性物质、全碳及全氮的变化成线性相关(R=0.99**)。在叶子分解前期，木质素、N素的绝对量有所增加，而水溶性物质则急剧减少。除紫椴叶外，其它几种叶子在分解过程中氮的含量有一定增加。但是，当红松、蒙古栎、春榆、白桦、山杨及色木叶中N素浓度分别为0.96%，1.41%，2.38%，1.67%，1.32%及1.32%时，则开始了N素的矿化释放。

STUDIES ON LEAVES DECOMPOSTION OF SOME TREE SPECIES IN CHANGBAI MOUNTAIN

In the Broadleaved-korean pine forest, the dry weight loss of the leaf of Pinus koreansis, Quercus mongloica, Acer mono., Betula platyphyla, Ulumus propinqua, Tilia amurrensis, and Populus davadiana after 300 days situ decomposition, is 24.2%, 37.6%, 30.8%, 44%, 47%, 50.6% and 55.6% respectively. During the incubation,the dry weight loss has a lineary relationship (R=0.99) with the tested chemical properties of the leavies. In the firest several months, the contents of the lignin and total nitrogen in the leavies are generally increased. In contrast, the water soluable substances are reduced rapitly.Except for basswood leaf, the other leavies can immobolize certain mount of nitrogen until reaching the critical points where the nitrogen content of the pine, oak, elm, birch, aspen, and maple leaf is 0.96%, 1.41%, 2.38%, 1.67%, 1.32%, and 1.32% respectively, From the critical points the leavies begin to release mineralized nitrogen.