Origins and microenvironments of bacteria mediating fecal pellet decomposition in the sea

摘要: The fecal pellets of zooplankton are thought to be major carriers organic matter from surface deeper waters the oceans. As descend, they release soluble components, partially due breakdown by associated microorganisms. Previous laboratory work other investigators has suggested that a pellet rapidly acquires bacteria, which increase in abundance until and their protozoan consumers disrupt membrane, spilling contents into water. In contrast, our field collections free-floating particle interceptor traps (from “Vertex” project off Central California 1980 Mexico 1981), suggest microbial decomposition probably is initiated sea inside pellets. Transmission scanning electron microscopy indicate bacterial populations most abundant interior obtained sea, but same will acquire lawn typically observed studies if maintained aboard ship. If decomposed inside, then principal agents enteric bacteria or ingested, digestion-resistant both. Such may differ metabolically those colonize surfaces. Further-more, healthy-appearing suggests metabolic activities produce microhabitats reduced oxygen tension could considerably exteriors. Decomposition these semi-enclosed microenvironments proceed manner not yet predicted models attribute well-aerated, surface-dwelling on sea.