关键词: 加拿大海盆;楚科奇海;好气异养细菌;沉积物岩芯;地理分布

Abstract:

The occurrence percentage and content of General Aerobic Heterotrophic Bacteria (GAB)were determined by using the method of MPN for 182 subsamples from 10 sediment cores taken from Canadian basin and Chukchi sea at two different culturing temperatures. The results showed that the general occurrence percentage of GAB was quite high, average contents of GAB at cultured temperatures of 4 ℃ and 25 ℃ were 4.46×107 and 5.47×107 cells·g (wt)-1 respectively. The highest GAB content occurred at 20—22 cm layer in the sediment. GAB contents waved among the strata of sediments, but a trend appeared that: contents in the middle or lower strata were lower than those of upper stratum. Cultivation at 25 ℃ could improve the occurrence percentage and contents of GAB, which suggests that the increasing of temperature may change the living circumstances and conditions of GAB. The differences of GAB among the latitudes areas indicated that occurrence percentage and contents of GAB in middle latitude areas were higher than those in the higher or lower latitude areas, and were more obvious at 4 ℃ than those at 25 ℃. The GAB contents in sediment under the shallower water seemed to be lower than those in sediments under the deeper water and this status was more obvious at 25 ℃ than that at 4 ℃.