干旱区生态环境知识资源中心

Research to evaluate the role of the soil algae in the initiation of pedogenesis in sandy areas and to establish the mineral, chemical and organic composition of soil-algal crusts was done. The investigations area is located in southern Poland in a landscape of drift sand (Bledowska Desert) formed as a result of medieval deforestation related to Ag, Pb and Fe mining activities. Fifteen species of algae (Cyanophyta, Chlorophyta and Heterokontophyta) were identified. In the soil-algal crusts, C-org contents ranged from 0.35-2.23%, P-avail from 9-34 mg . kg(-1) and N-t was variable. In investigated area the ground on which soil algae developed was acidic (pH 4.4-5.7 in KCl). Among mineral components in the crust, phases rich in Fe and K dominated (776.5(+/- 2.3) - 2803(+/- 31) mg . kg(-1) and 230.5(+/- 3.7) - 696(+/- 22) mg . kg(-1), respectively) and elevated concentrations of Zn, Mn and Pb occurred. Soil-crust organic matter includes aliphatic and aromatic compounds, carbohydrate derivatives, phenols, furan and pyrene structures. N compounds have significant contribution in composition of soil-algal crusts - the algae are main source of organic matter in this stage of soil formation. It could accelerate the regeneration of disturbed ecological systems.