Effect of artificial tree stands on physical, chemical properties and soil microbial ‎biomass (case ‎study: Zaghmarz of Neka)‎

In the present study, physical, chemical, and biological soil properties in pure plantation stands (21 years old) of Alnus subcordata, Populus deltoides, Cupressus sempervirens, and a mixed stand of Alnus subcordata-Populus caspica at Zaghmarz area, Neka city (north of Iran), were studied. In each stand, 10 plots of 400 m2 were selected and in each plot five samples were taken from 10 cm-depth of soil. The highest values of soil water content, pH, total nitrogen (N), phosphorus (P), potassium (K) and magnesium available (Mg), basal microbial respiration (BMR), soil microbial biomass nitrogen (MBN) allocated to stands of A. subcordata–P. caspica and A. subcordata, while the highest amounts of organic carbon (C), C:N ratio, microbial biomass carbon (MBC), and MBC/MBN ratio was observed in Cupressus stand. Analysis of PCA showed that Cupressus plantation has a positive correlation with the amount of C, CN, silt, clay, MBC, and MBC/MBN. But the pure and mixed stands of Alnus are positively correlated with total N, K, Ca, Mg, P available, water content, BMR, and MBN, showing the soil fertility of these stands and encouraging users to cultivate this species in the form of afforestation or agroforestry.