Analysis of the O2 dependency in leaf‐level photosynthesis of two Reynoutria japonica populations growing at different altitudes

摘要: To examine the effects of decreased CO2 and O2 partial pressure on leaf-level photosynthesis in alpine plants at high altitude, we compared maximal carboxylation efficiency, CE, Reynoutria japonica Houtt. var. growing a highland with one lowland. CE under native atmospheric conditions (native CE) population was significantly lower than that lowland one. The dependency less Using theoretical analysis, explained became as internal conductance (gi) decreased. We also showed gi content active Rubisco (E) could be estimated from photosynthesis. By applying severe limitation diffusion leaf population, whereas almost same values E were both populations. A reasonable explanation for difference is smaller photosynthetic capacity caused by addition to differences pressures O2.