determination of some erodibility indices of oriental beech (Fagus orientalis Lipsky.) stands in Sinop region

Soil erodibilty refers to the susceptibilty or resistance or resistance of soil to detachment and transport of aggregates by erosive forces for a particular site. In this study, Erodibility indices and vulnerability of beech soils was determined according to altitudinal zones. Study was conducted in pure oriental beech stands in Sinop, Erfelek, Bektasaga and Ahmetyeri provinces. Soil samples were collected from five different altitude levels and two different aspect. Each altitude level has 10 soil profiles (5 on north aspect, 5 on south aspect), total of 50 soil profiles. Total of 218 soil samples were collected from these soil profiles. Some physical (texture, moisutre, avaible water capacity, dispersion percent, erosion percent, clay percent) and chemical (organic matter, pH, electrical conductivity and total lime content) characteristics of soil were analysed. According to results, soils under oriental beech stands were generally susceptible to erosions. Dispersion percent (27.25%) and erosion ratio (25.23) were over the limit values. Colloid/moisture equivalent ratio showed that only soils in forth altitude level (600-800 m) were resistant to erosion while all other soils were susceptible to erosion. Even though most of the soils were susceptible to erosion, it is observed that with increase in altitude the resistance to erosion was also increasing.