单性木兰生存群落凋落物及土壤水文生态效应

Litter and Soil Hydrological Characteristics in Kmeria Septentrionalis Communities

[目的] 分析广西壮族自治区木论自然保护区单性木兰成片分布区群落的凋落物和土壤水文效应，为更好地评价单性木兰生存群落的水文生态效应提供依据。[方法] 在单性木兰成片分布区内，采用样方法，对单性木兰生存群落林下凋落物层和土壤层水文生态做定量研究。[结果] 林分凋落物现存量为11.68 t/hm^2，最大持水总量为19.46 t/hm^2，有效拦蓄能力为13.87 t/hm^2；半分解层凋落物现存量远大于未分解层，占整个蓄积量的77.06%，其有效拦蓄量也占整个拦蓄量的75.56%。林分土壤容重、总孔隙度、毛管孔隙度、非毛管孔隙度分别为1.14～1.26 g/cm^3，51.36%～68.68%，41.58%～45.73%，8.80%～27.10%，土壤最大持水量和有效持水量分别为868.75～941.04，64.00～133.73 t/hm^2。林地总蓄水量变化范围79.75～148.74 t/hm^2。[结论] 单性木兰成片分布区林地蓄水功能主要集中在土壤层中，林分密度对土壤容重和土壤有效持水量有显著影响。

[Objective] The aim of this study is to analyze the litter and soil hydrological characteristics in Kmeria septentrionalis communities in Mulun nature protection zone in Guangxi Zhuang Autonomous Region, in order to provide the basis for the evaluation of hydrological effects of K. septentrionalis communities.[Methods] In a continued area distributed with K. septentrionalis in Mulun, sampled plots were set to quantitatively investigate the hydrological characteristics of ground litter and soil.[Results] The litter volume was 11.68 t/hm^2, and the maximum water holding capacity was 19.46 t/hm^2. The available water interception was 13.87 t/hm^2, which was equivalent to 1.39 mm rainfall. The volume of semi-decomposed litter was greater than the volume of litter in non-decomposed layer, which accounted for 77.06% of total litter volume and produced 75.56% of the total litter interception. Soil bulk density, total porosity, capillary porosity and non-capillary porosity was from 1.14 to 1.26 g/cm^3, 51.36% to 68.68%, 41.58% to 45.73%, 8.80% to 27.10%, respectively. Soil maximum water capacity and effective water holding was 868.75～941.04 t/hm^2 and 64.00～133.73 t/hm^2, respectively. The forest＇s total water capacity ranged from 79.75 to 148.74 t/hm^2.[Conclusion] The water interception in K. septentrionalis distributing area was mainly concentrated in soil layer, and the stand density significantly affected soil bulk density and available water storage.