北京地区重要古树土壤物理性状分析

Analysis on Soil Physical Properties of the Old Trees in Beijing

以北京地区的代表性古树白皮松、侧柏、油松和国槐为研究对象,采用环刀法和烘干法对其土壤物理性质进行了测定,分析了不同类型古树土壤物理特性状况,为古树种的健康生长评价提供有效依据,并在一定程度上指导古树的复壮技术等。结果表明:(1)土壤含水量均值为10.6%,4种古树的土壤含水量均值表现为白皮松>油松>国槐>侧柏;(2)土壤容重均值为1.20g/cm3,4种古树之间的差异不显著;(3)土壤的总孔隙度、毛管孔隙度和非毛管孔隙度的均值分别为20.7%,11.8%,9.0%,4种古树差异不显著,土壤通透性均不良。(4)土壤紧实度均值为2.19kg/m2,地域性差异显著。通过本文研究,可初步判断这4种古树的土壤物理条件并不是最适合植物生长的状态。

As the representative of old trees,Pinus bungeanaas,Pinus tabulaeformis,Platycladus orientalis and Sophora Japonica were selected as the examples.Adopting cutting ring method and drying method,their soil physical properties were determined and analyzed in order to provide an effective basis for evaluating health of old trees and direct the rejuvenation of old trees etc.The results show that：（1）average soil water content（SWC） was 10.6%,but the SWC of different tree species are not same,and it presented as Pinus bungeanaasPinus tabulaeformisSophora japonicaPlatycladus orientalis;（2）the mean bulk density of soil samples was 1.20 g/cm3,and their differences were not significant;（3）the average total porosity,mean capillary porosity and medial non-capillary porosity of soil samples were 20.7%,11.8%,9.0%,respectively,and there were not obvious differences among these soils supporing these species,the soil permeability is not good;（4） mean soil compaction is 2.19 kg/m2,and the regional differences are significant.In this study,we could initially determine that the soil physical conditions for the 4 tree species were not the suitable ones for plant growth.