Abstract: The relation between the trace elements and the diatom communites is described by the analysis of the composition of diatom communities in a cold spring in Changbai Mountain. The resuits are as follows: 1. Diatoms are the dominant populations in the waterbody and among them there are a large number of Diatom mesodon (Ehr.) Kutz. This is related to a great quantity of pumicestone around the waterbody; 2. The existence of Eunotia, Pinnularia, Gomphonema etc. is related to the Fe content in the waterbody; 3. D. mesodon belongs to halophile formen in oligohalobe formen, while the other kinds of species, such as some species of Eunotia and Pinnularia belong to halophobe in oligohalobe formen.

Key words: Micro-habitat, Diatom communities, Trace element