Effects of imposed salinity gradients on dissimilatory arsenate reduction, sulfate reduction, and other microbial processes in sediments from two California soda lakes.

ABSTRACT: Salinity effects on microbial community structure and on potential rates of arsenate reduction, arsenite oxidation, sulfate reduction, denitrification, and methanogenesis were examined in sediment slurries from two California soda lakes. We conducted experiments with Mono Lake and Searles Lake sediments over a wide range of salt concentrations (25 to 346 g liter(-1)). With the exception of sulfate reduction, rates of all processes demonstrated an inverse relationship to total salinity. However, each of these processes persisted at low but detectable rates at salt saturation. Denaturing gradient gel electrophoresis analysis of partial 16S rRNA genes amplified from As(V) reduction slurries revealed that distinct microbial populations grew at low (25 to 50 g liter(-1)), intermediate (100 to 2

SUBMITTER: Kulp TR 

PROVIDER: S-EPMC1950999 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature