【Objective】 This study aimed to clarify the species compositions and the ecological habitats of diatoms from Huoditang forest region of Qinling Mountains.【Method】 Samples collected from 8 locations of Huoditang forest region of Qinling mountains were acidized before being observed using microscope,the number was counted and pictures were taken.Then the species compositions of diatoms were studied,and their ecological habitats and the characteristics of distribution were analyzed as well.【Result】 A total of ...