不同林分密度邓恩桉凋落物及土壤持水特性

Effect of Stand Density Differences on Litterfall and Soil Water Holding Capacity of Eucalyptusdunnii Plantations

以广西10年生的3个密度邓恩桉人工林为研究对象,对比分析了不同林分密度林下凋落物和土壤及持水特征的变化规律。结果表明:3个密度林分的林下凋落物贮量为18.5~19.6 t·hm^(-2),最大持水量为31.5~40.7 t·hm^(-2),均是高密度的最小;3个密度邓恩桉林地的土壤总孔隙度、毛管孔隙度、饱和持水量、毛管持水量和田间持水量均是高密度最大,土壤容重是高密度最小,但土壤非毛管孔隙度为中密度最大,低密度最小。

Eucalyptus dunniiplantations with three stand densities were selected in Guangxi, and litterfall, water holding capacity and soil water holding capacity were investigated in these stands to understand relationships between stand density and these parameters. Results showed that the litter accumulation across the three stand densities ranged from 18.5 to 19.6 t·hm^（-2）, and the range of maximum water holding capacity was 31.5 to 40.7 t·hm^（-2）. All the indices of litterfall and accumulation were lowest at the highest stand density. For soil water holding capacity, the total soil porosity, capillary porosity, saturated moisture content, capillary water capacity and field moisture capacity were all highest at the highest stand density, but soil bulk density was lowest at the same density. The lowest soil non-capillary porosity was found at the lowest stand density and was at its highest at the intermediate standdensity.