Dynamic changes of leaf growth and three physiological indexes of Platanus×acerifolia(Ait.) Willd.were studied in leaf expansion stage.The results show that in leaf expansion stage(April 4 to April 26),the weight and area of individual leaf increase gradually,and reach their peaks on April 26 and rise to 9.8 and 39.2 times of that in the initial stage,respectively.With the growth of P.×acerifolia ……