Broad-leafed deciduous forest ecosystems of Central Europe

The Broad-Leaved Forest ecosystems are widespread in regions of Sub-Boreal climate zone with a well balanced precipitationrevapotranspiration ratio. The southern periphery of the vast belt of Eurasian boreal and Sub-Boreal Forest ecosystems is represented by Oak Forest ecosystems. These ecosystems exhibit both the largest biomass and annual NPP rates in comparison with other forest ecosystems of this zone. However, the dead mass surface organic matter is 2-3 time less than that of coniferous forests. 

The content of nitrogen in fallen leaves as a major shedding component is about twice as much as that in the needles of coniferous trees. The total sum of ash elements in the leaves accounts for 3-5%, average about 4% on dry weight basis. Accordingly, the concentration of calcium increases from 0.5 to 4.0%, potassium from 0.15 to 2.0% and silicon with a wide variation. The row of nutrient uptake is as the following  

The amount of nitrogen in the biomass of the Oak Forest ecosystem reaches 900-1,200 kg/ha and the sum of ash elements is about 2,000-3,000 kg/ha, e.g., greatly in excess of nitrogen. The corresponding values for accumulation of nitrogen in annual growth are 80-100 and for ash elements, 200-250 kg/ha. An essential point is that the green leaves store 70-80% of the mass of uptaken elements, and the fallen leaves, 

80-90% of the mass of elements eliminated from the biological cycle. Nitrogen as returned in the shedding products, amounts to 40-70 kg/ha, and the ash elements, to 180-200 kg/ha (see Box 2). 

Biogeochemical fluxes of elements in Oak Forest ecosystem (after Jakucs, 1985) 

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