Characterization of some luvisols of the Ampoi Basin, Alba county

Abstract

The Ampoi Basin is situated in the south-eastern side of the Apuseni Mountains. The bioclimatic conditions typical of this region are favourable to clay migration process. Because of the relief and parent material features, in this area there are Luvisols only on small areas, which are represented by Stagnic Luvisols and Alic- Stagnic-Albic Luvisols. In this scientific paper, we have shown the soil formation factors, which determined Luvisol development, soil morphology, physical and chemical characteristics. Stagnic Luvisols are spread on the Ampoi Terrace, on quasihorizontal area. The parent materials on which these soils developed were Holocene loamy alluvial-proluvial deposits. Land was used as hayfields. The morphological profile was represented by Ao, El, EBw and Btw horizons. Alic-Stagnic-Albic Luvisols were spread in the north side of low slopes from the Metaliferi Mountains. The parent materials on which these soils developed were loamy deluvial deposits with substratum made of Tortonian sandstone and conglomerates. Land was used as weakly developed grassland. The morphological profile was represented by Ao, Ea, EBw and Btw horizons. The bioclimatic area was represented by broadleaved trees-Quercus petraea forest. Soil response was highly acid (pH 4.7) and oligo-basic base saturation degree (V8.3=11- 23%), found in the Btw horizons contributed to frame these soils to alic soil subtype of this Luvisols. The analysed soils did not fulfil all the conditions for belonging to the Alisol class.