GREENHOUSE GAS FLUXES AND CARBON LOSSES FROM SOIL IN DECIDUOUS FORESTS WITH NATURALLY WET AND DRAINED MINERAL SOILS

Abstract

The scope of the study is to evaluate soil greenhouse gas (GHG) fluxes from drained and naturally wet (pristine) nutrient rich mineral forest soils representing Mercurialosa mel. (drained) and Myrtillosoi-polytrichosa and Drypteriosa (wet soil) forest stand types with dominant species (aspen, birch and black alder). GHG were monitored during 12 month period using opaque chamber method. Gas samples were collected once per month and carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) concentration was determined using gas chromatography. The calculated GHG fluxes were evaluated in conjunction with temperature, soil moisture and groundwater level measurement results. We did not found difference of the soil GHG fluxes in drained and pristine wet mineral soils. The N₂O and CH₄ emissions from soil are negligible; however, periodic extreme increase of CH₄ is characteristic for pristine wet soils, pointing out that wet mineral soils can be significant source of GHG emissions, just like organic soils. CO₂ emissions are correlating with air and soil temperature, while CH₄ and N₂O emissions are not correlating with any of the monitored environmental variables.