Comparative Analysis of Salix babylonica and Salix matsudana for Their Cadmium Accumulation, Growth and Photosynthesis in Response to Cadmium Contamination Uptake kinetic characteristics of Cu2+ by Salix jiangsuensis CL J-172 and Salix babylonica Linn and the influence of organic acids Quick Response to Salt Shock in Willow Effects of Doubled CO2 Concentration on Light Energy Absorption and Excitation Energy Distribution Between PS II and PS I in Chloroplasts of Weeping Willow and Eucommia DEVELOPMENTAL ANATOMY OF FLORAL NECTARIES IN SALIX BABYLONICA