Effect of forest site types on the exchangeable and water-soluble cations distribution in the soil profiles

The aim of this research was to assess the impact of forest site types on the ionic composition of the soil sorption complex and soil water extracts in a soil profile. Three forest site types: coniferous forest (CF), coniferous-deciduous forest (CDF), and deciduousconiferous forest (DCF), were selected for the studies. Three dominant soil types were distinguished on the studied plots: Haplic Podzol, Dystric Arenosol, and Dystric Cambisol. Calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and aluminium (Al) in the soil sorption complex and soil water extracts were determined. Ca is a dominant cation in the soil sorption complex in organic horizon, while Al in mineral soil horizons. The differences between forest site types in ionic composition of soil water extracts were observed, mainly in the organic horizon and the horizons below the rooting zone. The vegetation affected the Ca/Al and base cations to Al molar (BC/Al) ratios. The Ca/Al and the BC/Al molar ratios increased in the sequence of sites: CF < CDF < DCF.