Effect of NaCl Tolerance on Photosynthetic Physiology and Growth of Seedlings of Three Poplar Clones Crown characteristics and spatial distribution of leaves of new poplar clones Effects of Light Stress on Oxygen Evolution and Photochemical Energy Storage of Hybrid Poplar Clones Determined by Photoacoustic Technique COMPARISON OF THE NET PHOTOSYNTHESIS RATE OF FOUR POPLAR CLONES AT DIFFERENT TEMPERATURE AND HUMIDITY REGIMES Effect of Temperature and Relative Humidity on Instantaneous Response of Four Poplar Clones to CO2 RESPONSES OF PHOTOSYNTHESIS AND PV-PARAMETERS TO WATER STRESS IN POPLAR CLONE SEEDLINGS Leaf area index and biomass productivity of mid and short rotation poplar plantations for pulp timber A Study on Rooting Characteristics of Cuttings of New Poplar Clones THE SELECTION AND ESTABLISHMENT OF LEAF AREA MODELS FOR CLONES OF POPULUS SPP. STUDIES ON DIRECTIVE SILVICULTURE OF POPLAR VENEER GLUED WOOD IN THE SOUTHERN REGION OF CHINA An Experiment on Introduction and Cultivation of Exotic Poplar Clones in Fuzhou Area