长白山主要次生林的枯落物现存量组成及持水特性

Litter's Reserve and Water-Holding Capacity for Major Secondary Forest Communities in Changbai Mountains

以吉林延边八家子林业局主要次生林群落为研究对象,对不同群落枯落物层的组成和现存量及其持水特性进行比较。结果表明,各群落枯落物现存量在4.67 5.13 t.hm-2之间,其顺序为落叶阔叶林>白桦林>红松阔叶林>杂木林;各群落枯落物组成均为未分解物大于半分解物,约占总量的60%左右。对不同枯落物类型的浸水实验发现,吸水强度以半分解物的吸水最快,其次为阔叶树种枯落叶和针叶树种枯落枝,而枯落草、阔叶树种枯落枝、杂类和针叶树种枯落叶相对较慢;不同枯落物类型的最大持水率和最大持水量均呈极显著差异,最大持水率为杂类>枯落草>针叶树种枯落叶>阔叶树种枯落叶>半分解物>针叶树种枯落枝>阔叶树种枯落枝,最大持水量为半分解物最大,其次为阔叶树种枯落叶、阔叶树种枯落枝,针叶树种枯落叶、针叶树种枯落枝、杂类和枯落草持水量相对较小。不同群落类型持水率表现为白桦林>落叶阔叶林>杂木林>红松阔叶林,最大持水率介于291.53%364.56%之间;持水量排序与持水率一致,最大持水量在13.64 18.00 t.hm-2之间,各群落持水率和持水量均随浸泡时间增加呈对数增长,可用W=alnt+b方程拟合,拟合结果极显著。

The litter＇s reserve and water-holding capacity were investigated by the methods of field survey and litter soaking experiments for major secondary forest communities in Bajiazi Forestry Bureau of Yanji,Jilin Province.The results showed that the litter reserve of all communities ranged form 4.67 t·hm-2 to 5.13 t·hm-2,with a rank of deciduous broad-leaved forest Asian white birch forest Korean pine broad-leaved forest mixed forest.The reserves of the undecomposed litter were more than that of the semi-decomposed litter,and occupied about 60% of the total.The water absorption strength varied significantly among different litter types,the fastest was the semi-decomposed litter,followed by broad-leaved litter,needle-branches litter,and grass litter,while that of the broad-branches litter,miscellany litter,needle-leaves were relatively slow.The maximal water-holding rate and the maximal water-holding capacity were significant different among different litter types,and the maximal water-holding rate followed the order of miscellany grass coniferous needles broad-leaves semi-decomposition coniferous branches broad-branches,and the maximal water-holding capacity followed the order of semi-decomposition broad-leaved broad-branches coniferous needles coniferous branches miscellany grass.The maximal water-holding rate of all communities ranged from 291.53% to 364.56%,and water-holding rate followed the order of Asian white birch forest deciduous broad-leaved forest mixed forest Korean pine broad-leaved forest.The maximal water-holding capacity of all communities ranged from 13.64 t·hm-2 to 18.00 t·hm-2,and with the same order for water holding rate.The litter soaking experiments showed that the water-holding rate and water-holding capacity increased with the soaking time,following a logarithmic curve（W=alnt＋b）,and fitting results were very significantly.