Heterotrophic Activity Throughout a Vertical Profile of Seawater and Sediment in Halifax Harbor, Canada

摘要: Abstract The relative heterotrophic activity of marine microorganisms was determined at two sites by the uptake technique throughout water column, sediment-water interface, and surface layer sediment. In greatest steadily decreased with depth. The percentage substrate that respired also depth from 69 to 56%. interface several orders magnitude greater than overlying twice sediment immediately below. Hand-collected samples carefully taken as close 1 cm had same characteristically low bottom few meters water. Microautoradiography 3H-labeled glucose, glutamic acid, or thymidine revealed a general decrease in active cells 35 <1%. number averaged <10% total population. data indicate is most region this system due an increased rather per-cell activity.