鼎湖山南亚热带森林细根分解干物质损失和元素动态  

Dry Mass Loss and Chemical Changes of the Decomposed Fine Roots in three China South Subtropical Forests at Dinghushan.

作　　者：温达志[1] 魏平[2] 张佑昌[2] 孔国辉[1] 

机构地区：[1]中国科学院华南植物研究所 [2]中国科学院华南植物研究所鼎湖山树木园

出　　处：《生态学杂志》1998年第2期1-6,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金;中国科学院"九五"重大项目

摘　　要：鼎湖山南亚热带森林细根分解干物质损失和元素动态温达志（中国科学院华南植物研究所，广州５１０６５０）魏平张佑昌（中国科学院华南植物研究所鼎湖山树木园，肇庆５２６０７０）孔国辉（中国科学院华南植物研究所，广州５１０６５０）ＤｒｙＭａｓＬｏｓａｎｄＣｈｅｍ...The experiments of decomposition of fine roots were carried out in pine forest(PF), pine-broadleaved mixed forest(PBF) and evergreen broadleaved forest(EBF) in the Dinghushan biosphere reserve. Regression analyses showed that the power function of X/X 0=e -kt with Adj.r 2(0.989- 0.993) very well fitted with the data of dry mass loss against time(year). The theoretical values of annual decomposition rate of roots with diameter≤2mm derived from the equations were 43.44%, 43.97%, 46.91% for PF,PBF and EBF respectively and also fitted very well with the measured values(43.15%, 43.90%, 45.68%). Decay coefficients(K) were 0.570 for PF, 0.579 for PBF and 0.633 for EBF. The decomposition rate of roots with diameter of 2-4mm is lower(38.54%) than that of roots with diameter≤2mm.No significant difference of the decomposition rates was found between the decomposing roots buried in mesh bags of 0.25mm and 1.00mm. At the 170th day, about 95% soluble carbohydrate was leached out. At the 300th day, The released rate ranged 20.2%-57.3% for N, 52.3%-82.5% for P, 68.6%-83.4% for K, 75.9%-79.1% for Mn and 41.7%-79.1% for Zn. The negative values(-14.8% to -70.2% for Ca, 5.2% to -59.6% for Mg) implied that a tendency of accumulation for element Ca and Mg occured during decomposition proceses.

关 键 词：森林 南亚热带森林 细根 干物质分解 元素 

分 类 号：S717.12[农业科学—林学] S718.556