大兴安岭重度火烧迹地植被恢复过程中枯落物持水特征

Litter Water-Holding Characteristics in the Process of Vegetation Restoration in Severely Burned Area of Great Xing'an Mountains

以大兴安岭重度火烧迹地不同恢复年限落叶松（Larix gmelinii）人工林为研究对象,对植被恢复过程中枯落物蓄积量及其持水特性进行比较研究。结果表明：（1）重度火烧迹地经过植被恢复枯落物厚度和蓄积量增加,恢复24a枯落物厚度和蓄积量均最高,分别为3.42cm和6.04t/hm^2。（2）植被恢复过程中枯落物层最大持水率为357.22%～576.41%,最大持水量为13.27～30.23t/hm^2,有效拦蓄深为0.53～1.45mm。枯落物半分解与分解层最大持水量和有效拦蓄深均高于未分解层。在植被恢复过程中,枯落物最大持水量和有效拦蓄深均表现出逐渐增大的趋势。（3）枯落物浸水4h时,持水量均超过其最大值的80%,浸水14h后吸水基本达到饱和。枯落物持水量（W）和吸水速率（V）与浸水时间（t）可用W=kln t＋p和V=ktn方程拟合,拟合结果极显著。

Based on Larix gmelinii plantation restored in severely burned area of Great Xing＇an Mountains,litter water-holding characteristics in the process of vegetation restoration were analyzed.The results showed that：（1）After plantation restoration,litter thickness and storage capacity of severely burned area increased.Litter thickness and storage capacity of plantation restored after twenty-four years was largest,it was 3.42 cm and 6.04t/hm^2 respectively.（2）The maximum water-holding rate of litter ranged from 357.22% to576.41%,while the maximum water-holding capacity of litter ranged from 13.27t/hm^2 to 30.23t/hm^2.Litter modified interception depth ranged from 0.53 mm to 1.45 mm.Litter maximum water-holding capacity and modified interception depth of semi-decomposed and decomposed layer was larger than undecomposed layer.Litter maximum water-holding capacity and modified interception depth showed an increasing trend with the increase of recover years.（3）When soaking four hours,water-holding capacity exceeded eighty percent.After soaking fourteen hours,water-absorption rates fell to zero.Litter water-holding capacity（W）and water absorption rate（V）following W =kln t＋pand V=ktn equation and the fitting results were very significantly.