LAUSR

The impact of blue spruce (Picea pungens) and reed (Calamagrostis villosa) cover on quantity and quality of upper soil layers was investigated. The research was conducted in the Jizerske hory Mts., Czech Republic (altitude 880 m, acidic spruce forest site type – 8K). Mean weight of dry matter of holorganic horizons was similar under both variants. Totally, there were accumulated 153 t/ha of dry matter of humus horizons in blue spruce and 174 t/ha in reed. Soil pH (KCl) varied from 3.7 to 3.2 under blue spruce stand and from 3.6 to 3.3 under reed. The differences of concentrations of nutrients (P, K, Ca, Mg) were not found significant either. Only L horizon showed significant differences: there were higher values of cation exchangeable capacity (T) and higher content of exchangeable bases (S) under reed. We found very similar forest-floor humus properties under both species. Therefore we can not state worsening of the soil conditions under blue spruce compared to areas covered with tested forest weed species.