不同林龄华北落叶松人工林枯落物储量及持水特性研究

对3种不同林龄阶段的华北落叶松人工林林下枯落物储量及其持水特性进行分析的结果表明:枯落物储量幼龄林、中龄林、近熟林分别为42.23、57.11、65.00t/hm2;各林龄林下枯落物最大持水量均是未分解层小于半分解层,未分解层最大持水量是其风干重的280%～374%,半分解层最大持水量是其风干重的408%～466%;3种林龄按林下枯落物未分解层持水量大小排序为近熟林>幼龄林>中龄林,按半分解层持水量大小排序为近熟林>中龄林>幼龄林。各林龄各层枯落物持水量与浸水时间之间的最佳拟合关系式为W=alnt+b;各林龄各层次枯落物吸水速率与浸水时间之间的关系式为S=ktn,在0—1h内吸水速率急剧下降,1h以后下降平缓,吸水作用逐渐减小。

Litter Reserves and Water-Holding Capacity of Larix principis-rupprechtii with Different Stand Ages

The paper studies the litter reserves and the water-holding capacity of three different stand ages of Larix principis-rupprechtii plantation.The outcomes show that the litter reserves of young forest,half aged forest and near mature forest is 42.23 t/hm2,57.11 t/hm2 and 65.00 t/hm2 respectively.The maximum water capacity of litter is undecomposed litter < half decomposed litter and the maximum water capacity of the undecomposed litter is 280% ~ 374% of the litter's dry weight,and the half decomposed is from 408% to 466% of the litter's dry weight under each stand ages.The order of the water capacity of the undecomposed litter is near mature forest > young forest > half aged forest.The sequence of the water capacity of the half decomposed litter is near mature forest > half aged forest > young forest.The relation formula of the water capacity and immersion time of each layer litter and each tree age is W=alnt+b;the relation formula of the water absorption rate and immersion time is S=ktn and the water absorption rate is falling rapidly within the first one hour and slowing down gradually one hour later.