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

2002

4 Abb., 23. Lit. Ang.

Unselbständiges Werk

13894

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.