Advance planting under mature Norway spruceand pine stands: survival and early growth.

This two-year research will help to evaluate advance planting as a means of introduction of broadleaf species in coniferous forests to improve site processes. The study focusses on the interdependence of tree growth and light supply and upon the improvement of nutrient cycling by means of introduction of broad leaf species. It will be carried out in a Norway spruce (Picea abies (L.) Karst.) stand in Upper Austria and in a red pine (Pinus sylvestris L.) stand in Lower Austria. The advance planting is done with seedlings of European beech (Fagus sylvatica L.), sycamore maple (Acer pseudoplatanus L.) and sessile oak (Quercus petraea (Mattuschka) Liebl.). Photosynthetic active radiation (PAR), leaf area index (LAI), and canopy density are documented to describe the light regime of the plantations. The growth-performance of the seedlings is documented by repeated measures of root collar diameter, annual height growth, nutrient analysis of the foliage and measurement of the site will be investigated by repeated compartimentalized sampling of soil, litter layer and standing biomass.