Simulation of Soil Hydrology and Establishment of a Nitrogen Budget of a Mountain Forest

2002

S. 42-45

4 Abb., 23. Lit. Ang.

Unselbständiges Werk

200082172

The water fluxes through the mountainous forest ecosystem "Mühleggerköpfl" were simulated by means of the mechanistic soil physical model Hydrus 1D. The objective was to set up a nitrogen budget in order to decide if the ecosystem accumulates nitrogen or if nitrogen leaks from the site. The simulated annual loss of N by percolation ranges between 0.4 and 1 g N m®¬yr®Ü and is smaller than the annual input by bulk and occult deposition, which combines to approx. 1.2-1.5 g N m®¬yr®Ü. Obviously the forest soil presently accumulates N. With an N inpute-rate exceeding the N output, the operationally defined status of N saturation is not yet reached. Comparing the magnitude of the N pool in the soil (several kg N m®¬) with the rate of the annual increase (a few g N m®¬yr®Ü), the process of N saturation is apparently slow.