A CHEMOAUTOTROPHICALLY BASED CAVE ECOSYSTEM

Microbial mats discovered in a ground-water ecosystem in southern Roma nia contain chemoautotrophic bacteria that fix inorganic carbon, using hydrogen sulfide as an energy source, Analysis of stable carbon and n itrogen isotopes showed that this chemoautotrophic production is the f ood base for 48 species of cave-adapted terrestrial and aquatic invert ebrates, 33 of which are endemic to this ecosystem, This is the only c ave ecosystem known to be supported by in situ autotrophic production, and it contains the only terrestrial community known to be chemoautot rophically based.