北京山区人工林枯枝落叶层养分动态分析

Nutrition dynamic analysis of litter layer in the plantations of Beijing mountainous area

为探讨不同人工林经营模式对土壤肥力的影响,该研究于2000年在北京九龙山地区设立样地,对华北落叶松、油松、白蜡人工林和椴栎杨天然次生林的枯枝落叶数量、养分含量、分解速率和养分归还量进行研究和分析。结果表明:①林下枯枝落叶储量的顺序为:油松>椴栎杨>落叶松>白蜡;②单位面积各营养元素的总量与枯枝落叶的储量及营养元素含量成正相关关系;③落叶松、椴栎杨林下枯枝落叶分解较快,油松和白蜡相对较慢;④对于枯枝落叶归还到土壤中的N、P、K数量,落叶松人工林最大,其次为椴栎杨天然次生林,油松和白蜡人工林最少。

In order to study the effects of various plantation management models on soil fertility, in 2000, the quantity, nutrition, composition and decomposing rate of litter layer in the plantations of Larix principisrupprechtii, Pinus tabulaeformis, Fraxinus chinensis and secondary forests mixed by Tilia mandshurica, T. mongolica, Quercus liaotungensis and Populus davidiana were studied in the sample plots of Jiulongshan Mountains in Beijing. The results showed that： 1 ） litter storage under the plantations and forests followed the order of Pinus tabulaeformis 〉 the mixed forests 〉 Larix principis-rupprechti 〉 Fraxinus chinensis ; 2） there is a positive correlation between nutritional quantity per area and litter storage as well as element content; 3 ） decomposition rates of the litter of Larix principis-rupprechtii and the mixed forests were faster than those of Pinus tabulaeformis and Fraxinus chinensis ; 4） as to the total quantity of N, P and K returning to soil from the decomposed litter, Larix principis-rupprechtii is the largest, then the mixed forests, Pinus tabulaeformis and Fraxinus chinensis are the smallest.