Greenhouse gas emissions (N2O, CO2 and CH4) from three forest soils near Vienna (Austria) with different water and nitrogen regimes

Greenhouse gas production from forest soils was measured during the 1997 vegetation period using closed chambers. Klausenleopoldsdorf 1 and Schottenwald differed significantly in NO3- and NH4+ concentrations but nor in climatic conditions and soil type, while Klausenleopoldsdorf 2 was characterized by high soil water content. N2O emission rates were highest at Schottenwald (70.0 mu g N2O-N m(-2) h(-1)), which was mainly due to higher NO3- availability. The lower N2O emissions at Klausenleopoldsdorf 2 (15.1 mu g N2O-N m(-2) h(-1)) indicated that denitrification proceeded entirely to N-2, conditioned by high soil water content. Klausenleopoldsdorf 1 and Schottenwald showed similar CO2 emissions and functioned as a sink for methane. At Klausenleopoldsdorf 2 methane was produced (30.7 mu g CH4 m(-2) h(-1)) and CO2 emissions were low, which can be attributed to anaerobic soil conditions.