小流域水土保持生态修复区森林枯落物的持水性能

Water-holding capacity of litter layer for different forest vegetation in ecological restoration of small watershed

在山东省邹城市刘庄小流域水土保持生态修复区内 ,对 5种森林植被类型的枯落物持水性能进行了研究。结果表明 :①枯落物层具有明显的蓄水、保水作用。不同森林类型枯落物最大持水率为 85 0 %～ 198 2 % ,其中阔叶林明显高于针叶林 ;但由于针叶林具有较大的枯落物蓄积量 ,因此 ,针叶林仍能维持较高的蓄水功能。不同森林类型枯落物最大持水量为 1 5 4～ 2 5 3mm ,其中针阔混交林和针叶林高于阔叶林 ,具体顺序为麻栎 +侧柏 >侧柏 >赤松 +侧柏 >麻栎 >刺槐。②不同森林类型枯落物持水量和吸水速率 ,随时间的动态变化规律基本相似。随浸水历时的延长 ,枯落物持水量呈增加趋势 ,但当枯落物在水中浸泡 8h时 ,持水量达到较大值 ,之后增加浸泡时间 ,持水量增加幅度较为平缓。不同森林类型枯落物吸水速率 ,在前 4h内变化最快 ,以后逐渐变缓 ,2 4h时吸水基本停止。③不同森林类型枯落物有效拦蓄水深为 0 6 1～ 1 4 3mm ,针阔混交林 >阔叶林 >针叶林 ;具体顺序为麻栎 侧柏 >刺槐 >麻栎 >侧柏 >赤松 +侧柏。

Water-holding capacity of litter layer for different forest vegetation was researched in ecological restoration of Liuzhuang small watershed, in Zoucheng city, Shandong province. Results indicate that: ①Litter layer of forest vegetation play an important role in water-holding capacity. The maximum water-holding percentage of litter layer for different forest vegetation is 85.0%～198.2%, being larger for broad leaf forest than that for coniferous forest. Coniferous forest is still remaining higher water-holding capacity, owing to the existing amount of coniferous litter is larger than that of broad leaved. The maximum water-holding capacity of litter layer for different forest vegetation is 1.54～2.53*!mm, being larger for coniferous-broad leaved mixed forests and coniferous forest than that for broad leaf forest , the order is Quercus acutissima and Platycladus orientalis>Platycladus orientalis>Pinus densiflora and Platycladus orientalis>Quercus acutissima>Robinia pseudoacacia. ②The dynamic course of water-holding capacity and water absorption rate are similar in different forest vegetation types. With the immersion time extending, the water-holding capacity is increasing. When the litter layer is immerged in the water for 8 hours, the water- holding capacity will reach the bigger value. From then on, with the time extending, the increasing range of water-holding capacity shows small. The water absorption rate of litter layer changes fastly in the front 4 hours, after then it becomes smooth. The litter layer stops absorbing water when it reaches the 24th hours. ③The effective interception of different forest vegetation was 0.61～1.43*!mm, coniferous-broad leaved mixed forests>broad leaf forest>coniferous forest, the order was Quercus acutissima and Platycladus orientalis>Robinia pseudoacacia>Quercus acutissima>Platycladus orientalis>Pinus densiflora and Platycladus orientalis.