The survey of physical and chemical properties of soils in Alder (Alnus subcordata) forests plantations in Tonekabon city

Forest soil is one of the main factors in forest ecosystem that with other ecological components determines vegetation distribution pattern. Natural areas such as forests have been severely harvest for various reasons in the past years which it has been made soil fertility reduction and production discontinuity. The aim of this investigation was to evaluate the physical and chemical properties of soils in Alder (Alnus subcordata) plantation in Tonekabon forests/North of Iran. For this purpose, at first, forested areas by pure stands of alder were identified. DBH and height of alder trees and their regeneration in each plot was measured. After gathering litter from the soil surface, soil samples were taken from 0-10 and 10-20 cm depths. The soil samples were transferred to laboratory and some important soil properties were identified. The results showed that the moisture in east aspect is more than west aspect. Also, there was a positive correlation between diameter at breast height, height and regeneration with moisture, Nitrogen, Phosphorus and organic matter and a negative correlation with clay, sand, electrical conductivity, pH and neutral material. Alder species can be used as a native species for plantation in similar soil conditions that it is economically and environmentally appropriate for northern forests.