Application of a three-dimensional model to assess the effect of clear-cutting on carbon dioxide exchange at the soil - vegetation - atmosphere interface

A three-dimensional hydrodynamic model was applied to derive the spatial patterns of the air flows and CO2 fluxes within and around a recently clear-cut area. Results of modeling experiments show a strong influence of the clear-cut on the spatial air flow and vertical and horizontal CO2 flux patterns. The CO2 fluxes at the soil surface, within and above a forest canopy varied significantly depending on weather conditions, prevailed wind direction and influenced by the geometry and size of the forest clearing, tree density and the distance from the forest edges. The rates of horizontal CO2 exchange near the ground surface especially within the downwind forest area and at the leeward forest edge were relatively large and comparable with vertical CO2 fluxes.