Alvinellids and Sulfides at Hydrothermal Vents of the Eastern Pacific: A Review

Open Access
Publisher Website
Google Scholar
Abstract
SYNOPSIS. At Eastern Pacific hydrothermal vents, alvinellid polychaetes are among the first metazoans to colonize newly formed surfaces of sulfide chimneys. In this environment of rapid mineral precipitation, alvinellids are confronted by steep physico-chemical gradients and high temporalvariability. This paper examines the interaction of alvinellids with chimney mineralization processes and then reviews what is known of mechanisms that could enable these worms to deal with potentially toxic levels of sulfide in their environment. Studies of sulfide chimneys consistently show mineralogy to be locally modified around alvinellid tubes. This may be linked to sulfide oxidation products that accumulate in tube material or to the circulation of seawater through the tube. At high worm densities, these local effects may have a significant influence on larger scale sulfide accretion processes that determine chimney morphology. Alvinellid polychaetes may have several lines of defense against sulfide. Tubes and mucous layers could act as passive barriers to reduce inward diffusion of sulfide across posterior surfaces. Colonization of epidermal and tube surfaces by bacteria that might be sulfide oxidizing, could create an active external barrier in some species. Sulfide oxidation by tissue homogenates has been demonstrated in two Paralvinella species, where it may serve to protect oxidative respiration from sulfide entering worm tissues. Sulfide binding in blood has not been studied in any of the alvinellids.

This publication has 0 references indexed in Scilit: