اثر نوع خاك بر برخي خواص كمي و كيفي صنوبر اورامريكن

Effect of soil type on some quantitative and qualitative charactristics of Populus X. euramericana (Dode) gunier

Qualitative and quantitative characteristics of Populus X. euramericana (Dode) guinier plantations on four soil types including grey-brown podzolic with organic matter (A), brown forest (B), grey-brown podzolic (C) and pseudogley (D) were investigated in west of Mazandaran province (north of Iran). In each soil type, three transects (replications) of 20 m x 33.3 m were chosen and all populus trees were measured. The results indicat that diameter at breast height (d.b.h.) with 26.8 and 25.8 cm is greater respectively on A and B soil types than on other ones. The highest height, respectively with 27.8, 27.7 and 26.9 m, belongs to the trees growing on A, B and C soils. Correlation curve between d.b.h. and height exhibits that height, particularly at d.b.h. > 20 cm is greater on C soil. The heighest index (124), showing the lowest relative stability rate, is related to C soil. There is a significance relationship, between crown form of trees and soil type, the same as stem quality. Generally, the current research reveals that from viewpoint of the better qualitative and quantitative conditions of Populus X. euramericana, A and B are the most suitable soil types of the investigated sites.