Fig. 3.

CO₂ fluxes in relation to changes in the most significant abiotic predictor a photosynthetically active radiation (PAR) versus net ecosystem exchange of CO₂ (NEE), b air temperature versus ecosystem respiration (R _e) and c PAR versus gross ecosystem photosynthesis (GEP) measured in July at Thiisbukta in grazed wet moss tundra (open circle) and 4 year old exclosures (filled circle). The data are from the five occasions CO₂ fluxes were measured over a 3-week period in July. Significant regression for the two treatments is shown. Positive fluxes represent an efflux of CO₂ whilst negative values indicate uptake of CO₂ from the atmosphere