تحقیقات جنگل و صنوبر ایران (Sep 2009)
Investigation on the site and silvicultural properties of Juniperus excelsa in natural forests of Ilan in Qazvin province
Abstract
In order to investigate the vegetative properties of Juniperus excelsa M.Bieb in relation to soil and physiographic factors, Ilan site in Qazvin province was selected. First, map of land units was produced by overlaying of slope, elevation and geographical aspects maps. Inventory of vegetative characteristics such as density, DBH, height, number of trees with single trunk, number of trees with non-symmetrical canopy, canopy cover (%), canopy diameter and seedling density was performed in every land units by measuring 3 sample plots of 1600 m2 surface area. Three soil samples were taken from each land unit from 0-20 cm depth of soil and CaCo3, pH and bulk density were measured in lab. Results showed that except for trees with non-symmetrical canopy and trees height in different slope classes, other vegetative characteristics had significant difference among the land units, aspects, slopes and elevations at significant levels of 99 and 95 percent. Also, there is a significant correlation between number of juniper seedling with physical and chemical characteristics of soil. Highest correlation was observed for lime percentage and number of juniper seedling (r = 0.54). There were positive and significant correlation between number of shrub plant, number of juniper trees, basal area and forest canopy percentage with number of seedling. Highest correlation was observed for forest canopy percentage and number of juniper seedling (r = 0.64). Therefore, the vegetative characteristics of Juniperus excelsa M.Bieb in the studied site have significant correlation with soil and physiographic factors.
