Abstract:

The content of sulphate reducing bacteria (SRB)of the 35 sediment samples was determined by using MPN technique in the survey areas of Bering Sea and Chukchi Sea. The average content of SRB in all samples tested is about 1.68×10 5 cells·g -1 (wet.), its variation is 0-2.28×10 6 cells·g -1 . The differences of SRB content were analyzed and compared among the surficial layers, subsurficial or mixed ones in varied areas and stations surveyed. Roughly speaking, the SRB content in the surficial layers was lower than that in the subsurficial and mixed ones. The determinable SRB content appears presumedly opposite trend, i.e. it seems that the content of SRB increases south or east in Bering Sea and north or west in Chukchi Sea respectively if drawing a line on Bering Strait. The result indicates the occurrence percentages of SRB at 4 different cultivation temperature and suggests that there are a lot of cold adapted bacteria there. The low environmental temperature is still mainly a controlling factor. There are quite a few mesopholic bacteria, and it can be deduced that an effect of suitable organic matter supply to the SRB from raising temperature after melting frozen period.