阔叶树种引入后马尾松人工林土壤水文物理性质研究

Research of Soil Hydrophysical Properties of Pinus Massoniana Plantation After the Introduction of Broad-Leaved Tree Species

为探究阔叶树种引入后马尾松人工林土壤水文物理性质,选择贵州省龙里林场马尾松纯林及引入阔叶树种(伯乐、桂南木莲、连香、深山含笑、油茶)后的马尾松混交林地为研究对象,采用环刀法、烘干法与室内浸泡法对林地土壤的水文物理性质进行了研究。结果表明:(1)不同林型土壤容重随土层的加深而增大,以马尾松+深山含笑(1.29 g/cm 3)林分类型下土壤容重最小,马尾松+连香(1.54 g/cm 3)林分类型下土壤容重最大。(2)土壤总孔隙度、毛管孔隙度、非毛管孔隙度、土壤最大持水量、毛管持水量与田间持水量均随着土层的增大而减小,这与土壤孔隙度和持水量呈显著正相关表现一致。(3)与纯林相比,土壤容重、孔隙度和持水量均以深根性树种改善效果最好,其中马尾松+深山含笑最优,马尾松+油茶其次,马尾松+连香最差。从土壤水文物理角度考虑,在今后马尾松水土保持林的建设过程中引入凋落物易分解的深根性树种有助于土壤结构的改良,使林分更好地发挥其土壤水文调节的能力,同时应尽量避免引入浅根性树种。

In order to explore the soil hydrophysical properties of Pinus massoniana plantation after the introduction of broad-leaved tree species,the Pinus massoniana pure forest and the mixed forest stands of Pinus massoniana after the introduction of broad-leaved tree species(Bretschneidera sinensis,Manglietia guinanensis,Cercidiphyllum japonicum,Michelia maudiae,Camellia oleifera)in Longli Forest Farm of Guizhou Province were selected as the research objects,and the forest soils characteristics and hydrological characteristics of the different stand types were studied quantitatively through by ring knife method,drying method and indoor soaking method.The results showed that:(1)the soil bulk density of different forest types increased with the depth of soil layer;the soil bulk density of Pinus massoniana and Michelia maudiae(1.29 g/cm 3)mixed forest was the smallest,and that of Pinus massoniana and Cercidiphyllum japonicum(1.54 g/cm 3)mixed forest was the largest;(2)soil total porosity,capillary porosity,non-capillary porosity,soil maximum water holding capacity,capillary water holding capacity and field water holding capacity all decreased with the increase of soil layer,which was consistent with soil porosity and water holding capacity;(3)compared with the Pinus massoniana pure forest,the introduction of deep-rooted tree species had the positive influence on soil bulk density,porosity and water holding capacity;for example,Pinus massoniana and Michelia maudiae was the best,followed by Pinus massoniana and Camellia oleifera mixed forest,and the worst was Pinus massoniana and Cercidiphyllum japonicum mixed forest.From the perspective of soil hydrophysical characteristics,in the course of the future construction of Pinus massoniana soil and water conservation forest,the introduction of deep root tree species with easy decomposition of litter can be preferred,which is helpful for the improvement of soil structure and the forest to better play its ability of soil hydrologic regulation,meanwhile,the introduction of shallow root tree species can be avoided as far as possible.