Abstract: Based on the investigation of the plants in Thuja sutchuenensis community, t
he life form spectra, leaf character, and hierarchical-synusia structure
 in the community were analyzed. The life form spectra of the plants in the comm
unity were 732% of phanemphyte, 18% of hemicryptophyte, 6% of geophyte, 2% of
chamaephyte, and 08% of annual plants. The leaf quality was mainly of papery a
nd conaceous, which occupied 488% and 364%, respectively. The dominant leaf
size was microphy (608%), dominant leaf margin was un-entire (568%), and do
minant leaf form was simple (86%). The T. sutchuenensis community had three
sub-layers, i.e. tree layer, shrub layer, and herb layer, with lesser interlayer p
lants. Each layer was respectively composed by phanemphyte evergreen coniferophy
te, broadleaf and deciduous broad-leaf plants, nanophanerophyte evergreen and d
eciduous broad-leaf plants, as well as hemicryptophyte, geophyte, and annual pl
ants.

Key words: Thuja sutchuenensis community, vascular plant life form, leaf character, hierarchical-synusia structure, principal component analysis, regression analysis, index weight, groundwater vulnerability.