Soil properties in plantations of sessile oak (Quercus petraea) and red oak (Quercus rubra) in reclaimed lignite open-cast mines of the Rhineland

When growing on highly fertile soils, the amount of soil nutrients (K+, Ca2+, Mg2+, and PO43−P) did not differ between the two plantations. However, when oak trees grew on the less-fertile soil, the amount of soil nutrients was significantly lower beneath red oak. The amount of soil nutrients beneath red oak was even lower than beneath 2-year-old Q. robur plantations; the soil properties of which are almost at the beginning stage of succession. The results suggest that nutrient depletion beneath red oak when compared to sessile oak is caused both by increased immobilization into woody biomass, and by increased recalcitrance of organic matter.