Based on the detailed statistic data of six sections from Changxingian stage to Triassic basement in Sichuan and Guizhou Provinces

five benthonic communities dominated by brachiopods on flat sea floor have been established. The relationships between the communities and the benthonic assemblsges are respectively: Lingula Community(BA

1

)-Qingtongia ovalis Community(BA

2

)-Oldhamina Community(BA

3

)-Peltichia Community(BA

3

)-Paryphella-Waagenites Community (BA

4

-BA

5

). Studied their characteristics and environmental locations

it is suggested that the factors controlling the distribution of brachiopod communities in the area are water depth

substrata

salinity and food supply.