-

-

-

Publication

-

-

-

Gerzabek, Martin H. ; Haberhauer, Georg ; Stemmer, Michael ; Klepsch, Sabine ; Haunold, Ernst

Paperwork

2004

-

-

Biogeochemistry <Dordrecht>, 70(1): p 59-69 Nitrogen dynamics in semi natural environments is crucial for the development and ecological stability of these systems. The present paper shows the results of the reinvestigation of a 15N tracer experiment, which was established in the Grossglockner massif in Austria at 2300 ma. s. l. in 1974/1975. We show that large quantities of nitrogen introduced by a single pulse labelling ( amounting to approximately 1.7% of the nitrogen in the system) into an alpine grassland remain in the soil plant system, with only 55% being lost during 27 28 years. In the first 10 cm of the four investigated soil profiles 40% of 15N was recovered, being mainly bound in organic forms. A simple site specific model was established on the basis of the results considering a biological, residual and labile N pool, the latter being the source for N losses. By the model a long mean residence time close to 100 years was derived for the remaining 15N.