Ecophyslological response of Pinus koraiensis seedlings to elevated CO2 N2O emission from woody plants and its relation to their physiological activities Diurnal Variation in Photosynthesis of Differently Directional Leaves in Hybrid Hazels (Corylus heterophylla×Corylus avellana) Effects of Oligochitosan on Photosynthetic Parameter of Brassica napus Seedlings under Drought Stress