Vegetation distribution and biodiversity maintain in riparian zone have been a hot topic recently， however， few studies have been conducted on the ecological adaptation of the endangered riparian dioecious trees. We explored the sex-related difference of Cercidiphyllum japonicum adults in number， morphology， leaf nitrogen（NRE）-and phosphorus-（PRE） resorption efficiencies， soil contents of water， nitrogen and phosphorus and the relationships of NRE or PRE with leaf N and P， soil contents of water， N and P or plant morphology. The number of females significantly decreased rather than males with increasing distance to riverside， resulting in a decrease in the sex ratio（females/males）. In long distance， the sex ratio was significantly male-biased（female/male=0.289； χ2=4.57， P<0.05）， N content of green leaves and PRE of males were higher than that of males， while these traits were similar both sexes near riverside. In addition， male NRE or female PRE was related to green leaf， soil water and nutrient， and height of C.japonicum（especially for males） were positive with NRE and PRE. Our results showed that there were sex-specific adaptive responses to river distance in C.japonicum， and female and male leaf NRE and PRE differently respond to leaf nutrient or soil factors. The requirement of near riparian habitat for females might limit its population distribution.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2021.05.017