小兴安岭十种典型森林群落凋落物生物量及其动态变化

Dynamic of litterfall in ten typical community types of Xiaoxing′an Mountain, China

在小兴安岭地区选取10种典型森林群落分别设置样地,研究该地区不同群落类型凋落物的年产量、月动态变化以及组成特征。结果表明:10种群落类型中年均凋落物量大小依次为椴树红松林(4.08t·hm-.2a-1)>蒙古栎红松林(3.83 t·hm-.2a-1)>云冷杉红松林(3.55 t·hm-.2a-1)>云冷杉林(3.44t·hm-.2a-1)>枫桦红松林(3.43t·hm-.2a-1)>山杨次生林(3.26 t·hm-.2a-1)>白桦次生林(3.04 t·hm-.2a-1)>枫桦次生林(2.96 t·hm-.2a-1)>杂木林(2.95 t·hm-.2a-1)>白桦落叶松林(2.91 t·hm-.2a-1)。凋落物各组分中均以落叶为主,约占凋落总量的60%以上,枝仅占凋落量的5.7%—9.4%.凋落物月动态模式主要有两种:单峰型的有蒙古栎红松林、椴树红松林、枫桦红松林、枫桦次生林、山杨次生林、白桦次生林、杂木林,高峰期在8—10月份;双峰型的有云冷杉红松林、云冷杉林、白桦落叶松次生林,前两种群落的凋落高峰期在4月和9月,后者高峰期在8月和10月。不同群落类型年凋落量差异显著,原始红松林凋落量高于天然次生林,且凋落高峰出现时间以及各组分所占比例与群落类型有关,同时也与树种生物学特性有关。

Ten typical forests were selected as plots in order to investigate the litterfall productions, composition and seasonal dynamics of different types litterfall production in Xiaoxing＇an Mountain. The results showed that annual litterfall production was in descending order： Tilia-Pinuskoraiensis（4.08t·hm-2·a-1）〉Quercusmongolica-Pinus koraiensis（3.83 t·hm-2·a-1） 〉 Picea sp.Abies nephlolepis-Pinuskoraiensis（3.55t·hm-2·a-1）〉Picea sp.-Abies.nephlolepis（3.44t·hm-2·a-1）〉 Betula costata-Pinus koraiensis（3.43t·hm-2·a-1）〉Populus davidiana forest（3.26 t·hm-2·a-1）〉Betula platyphylla（3.04 t·hm-2·a-1） 〉 Betula costata（2.96 t·hm-2·a-1）〉 miscellaneous wood forest（2.95 t·hm-2·a-1）〉 Betula platyphylla-Larix gmelinii（2.91 t·hm-2·a-1）.litter production had no significant differences. needles accounted for more than 60% of the total litter,branches accounted for only 5.7%-9.4%. There are two seasonal dynamics of litterfall production in ten different community types,the annul dynamics of the forest litter in Betulacostata,Quercusmongolica-Pinus.koraiensis,Populusdavidiana,Betulacostata-Pinuskoraiensis,Betula platyphylla,miscellaneous wood forest appeared to be single climax curve,in which the highest point occurred in August to October.Picea,sp.-Abiesnephlolepis-Pinus koraiensis and Picea sp.-Abies nephlolepis was double peak and the highest point occurred in April and September.Betula platyphylla-Larix gmelinii also was double peak and the highest point occurred in August and October.The annual litterfall productions was significantly different among in different community types, primary Korean pine forests was higher than natural secondary forests, but litter components and the peak values appeared at different periods of time were mainly associated with community types in Xiaoxing＇an Mountain.