Effect of eco-physiological response in afforested plantation under elevated CO₂ condition

The interactive effect of increasing CO₂ concentration and eco-physiological effect in trees was studied in Sivagangai District of Tamil Nadu, South India. Afforested tree species viz., Tectona grandis, Gmelina arborea, Dalbergia sissoo, Bambusa vulgaris var. vulgaris and Swietenia macrophylla were planted and assessed for ecophysiological traits such as photosynthesis rate and stomatal conductance under different elevated CO₂ concentrations (ambient, 550 ppm, 700 ppm, 850 ppm and 1000 ppm). Among the five tree species tested, Gmelina arborea, Dalbergia sissoo and Tectona grandis showed positive response towards ecophysiological activities at different elevated CO₂ concentrations from 550 ppm to 1000 ppm. Moderate and poor response towards elevated CO₂ concentrations was observed in Swietenia macrophylla and Bambusa vulgaris var. vulgaris, respectively.