胡桃楸天然次生林凋落物分解的生态学过程

摘要

Using the method of timing acquisition and monitoring,the ecological process of litter decomposition of the natural secondary forest of Juglans mandshurica in the eastern mountain area of Liaoning Province were stud-ied.Result shows that the proportion of dry matter of leaves among the litters in the natural secondary forest of Juglans mandshurica is the largest,followed by that of branches,and that of flowers and fruits is smaller;the lower C/N of leaf in the litter,the higher nitrogen content,the faster litter decomposition,C/N has a negative cor-relation with litter decomposition rate;the average weight loss rate of dry matter of litter is 17.28% from May to September,the lowest weight loss rate is 9.73% in May;the weight loss rate correspondingly increases monthly from June to August,and of which the highest weight loss rate is 22.37% in August,and the lower weight loss rate is 20.17% in September;litter decomposition rate has a binary equation relationship with precipitation,air tempera-ture,air humidity,soil moisture and natural moisture content of litter;multivariate linear regression significant a-nalysis of main environmental factor which affect litter decomposition process shows that precipitation is the domi-nant factor of litter decomposition,and the natural moisture content follows behind.%采用定时定位采集与监测的方法,对辽东山区胡桃楸天然次生林凋落物分解的生态学过程进行了研究。结果表明：胡桃楸天然次生林凋落物中叶的干物质量比重最大,枝次之,花和果比重较小；凋落物叶中 C/N 越低,氮元素含量越高,凋落物分解得越快,C/N 与凋落物分解速率呈负相关关系；5—9月凋落物干物质平均失重率为17.28%,其中5月失重率最低,为9.73%,随后的6—8月失重率逐月增加,8月失重率最高,为22.37%,9月失重率略有降低,为20.17%；凋落物分解速率与降水量、空气温度、空气湿度、土壤湿度和凋落物自然含水率都呈显著的二次函数关系；影响凋落物分解过程主要环境因子的多元线性回归显著性分析表明,降水量是影响凋落物分解的主导因子,凋落物自然含水率的影响次之。