Bacterial uptake of dissolved organic matter in relation to detrital aggregation in marine and freshwater systems1

摘要: Microbial uptake of 3H-labeled glucose and acetate was studied in water samples from various depths the Pacific Ocean Lake Tahoe, California. Microzones incorporation were identified by comparison autoradiographic detection organic substrates with scanning electron micrographs detritus (nonliving particulate matter associated microflora). In both freshwater marine systems, immediate (within 4 hr) accumulation dissolved compounds detected mainly bacterial cells filaments. With continued incubation, label dispersed throughout detrital particles, localization greatest bacteria. Uptake attached microorganisms significantly higher cuphotic than aphotic zone as extent aggregation. Autoradiographs show that assimilated bacteria are linked to formation capsular materials, which important building aggregates.