红松阔叶林4种凋落物分解速率及其营养动态1）

摘要

2012—2013年在吉林蛟河天然红松阔叶林中，应用凋落物降解袋法研究了红松（ Pinus koraiensis）、蒙古栎（ Quercus mongolica）、紫椴（ Tilia amurensis）和色木槭（ Acer mono）4个主要优势乔木树种的凋落物分解速率及其营养动态。研究结果表明：4个试验树种的凋落物失质量率均随时间进程增大，但是和时间不成线性关系。在整个分解进程中，凋落物的分解速率开始明显升高，中后期开始分解速率逐渐平稳；阔叶凋落物分解速率高于针叶分解速率。通过模型模拟，4个树种的分解系数k值依次为红松（0．53±1．03）、蒙古栎（0．77±1．27）、紫椴（1．60±0．52）、色木槭（1．50±1．81），林中主要凋落物95％分解时间约为5～7 a。分解进程中，有机碳、全氮、全磷、全钾质量分数呈动态变化，4个树种的N和P均表现出富集现象，N在短期富集后强烈释放；C和K表现为净释放；w（ C）／w （ N）持续下降。%We studied the litter decomposition rates and nutrient dynamics of four dominant tree species including Pinus koraien-sis, Quercus mongolica, Tilia amurensis and Acer mono in the Korean pine-broadleaved forest from 2012 to 2013 in Jiaohe of Jilin Province.The litter decomposition rates of the broad-leaved tree species is higher than those of conifer ’s.The an-nual leaf decomposition rates (k) were 0.53±1.03 for Pinus koraiensis, 0.77±1.27 for Quercus mongolica, 1.60±0.52 for Tilia amurensis and 1.50±1.81 for Acer mono.It took 5-7 a to decompose 95%of leaves for major tree species .During the decomposition , N concentration and P concentration in the litters decreased rapidly at the first of decomposition , and then varied insignificantly .C concentration and K concentration from four tree species had net release during decaying , and the ratio of C to N decreased .