Photosynthetic pathways and life forms in different grassland types from North China

Photosynthetic pathways (C-4, C-3, and CAM species) and plant life forms of three grassland types in North China were compared. Of the total 201 species, 144 species in 78 genera and 34 families had C-3 photosynthetic pathway, 56 species in 35 genera and 11 families had C-4 photosynthetic pathway, and I species had CAM photosynthetic pathway. The number of C-4 Species in Songnen meadow was 70-80 % greater than that in Xilinguole steppe and Hunshandak desert grassland, but that for C-3 species did not differ significantly among the three grassland types. The number of therophytes in the Songnen meadow was relatively greater than that of the other two grassland types, but that of hemicryptophytes was lower. Thus the distribution of C-4 species and plant life form is probably related to precipitation.