Comparing the Effects of Planting Populous Deltoids and Fraxinus excelsior on Some Physical and Chemical Properties of Soil (Case Study: TazehabadJoonka, SiahkalCounty)1

This research was conducted to compare some of the physical and chemical properties of soil in relation to two grosses of planting Populousdeltoids and Fraxinus excelsior in Siahkal (TazehabadJoonka’s forests). For so doing, after designing the demographic network in 50×50 dimensions and by considering the (1/25000) scale and map’s area in two planting zones, 15 points were selected for sampling on the map for each zone and Random Systematic sampling method was chosen to sample the soil. In order to assess the properties of soil, in each zone, 10 soil profiles were dugin 0-10 meter depthand after transferring the samples to laboratory, sample’s properties such as texture, exterior specific mass, electric conductivity, acidity, organic Carbon, C/N ratio, Nitrogen, Calcium, Phosphorous, Potassium, Phosphataze acid and Alkaline phosphataze enzymes were measured. SPSS software and non binary T-test were used to analyze the data. The results showed that planting Populous deltoids and Fraxinus excelsior species causes no meaningful difference in exterior specific mass, electric conductivity, acidity, organic Carbon, Nitrogen, Calcium, Phosphorous, Potassium, Phosphataze acid and Alkaline phosphataze enzymes’ values. However, soil’s C/N ratio revealed that there is a meaningful difference between two grosses at 95% confidence interval. The higher amount of this value in Fraxinus excelsior gross than Populous deltoidsmeans that organic Carbon is higher in Fraxinus excelsior gross. Additionally, the higher amounts of Nitrogen and Alkaline phosphataze enzyme in Populous deltoids gross compared to Fraxinus excelsior demonstrates the higher effect of this gross on microorganisms’ activity and soil’s productivity.