Ozone flux over a Norway spruce forest and correlation with net ecosystem production

Daily ozone deposition flux to a Norway spruce forest in Czech Republic was measured using the gradient method in July and August 2008. Results were in good agreement with a deposition flux model. The mean daily stomatal uptake of ozone was around 47% of total deposition. Average deposition velocity was 0.39 cm s−1 and 0.36 cm s−1 by the gradient method and the deposition model, respectively. Measured and modelled non-stomatal uptake was around 0.2 cm s−1. In addition, net ecosystem production (NEP) was measured by using Eddy Covariance and correlations with O3 concentrations at 15 m a.g.l., total deposition and stomatal uptake were tested. Total deposition and stomatal uptake of ozone significantly decreased NEP, especially by high intensities of solar radiation.

► We estimate ozone deposition flux to a Norway spruce forest using the gradient method and model. ► The mean stomatal uptake of ozone is approximately 47% of the total deposition. ► We measure net ecosystem production (NEP) using Eddy Covariance. ► We test whether elevated total deposition and stomatal uptake of O3 imply a reduction of NEP. ► Deposition and stomatal uptake of O3 decrease NEP, especially by high intensities of solar radiation.