Microbial Ecology

, Volume 11, Issue 2, pp 107-115

First online:

Variation of environmental features and microbial populations with salt concentrations in a multi-pond saltern

  • F. Rodriguez-ValeraAffiliated withDepartamento de Microbiologia, Facultad de Medicina, Universidad de Alicante
  • , A. VentosaAffiliated withDepartamento de Microbiologia, Facultad de Farmacia, Universidad de Sevilla
  • , G. JuezAffiliated withDepartamento de Microbiologia, Facultad de Medicina, Universidad de Alicante
  • , J. F. ImhoffAffiliated withInstitut für Mikrobiologie der Universität

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


A multi-pond saltern that creates a gradient of salt concentrations has been studied with respect to some characteristics of the resulting environments and their microbial populations. The increase in salt concentration was correlated with increase in diurnal temperature and biomass present and with decrease in oxygen concentrations. Many types of organisms below 15% (w/v) total salts, were found, many of them normal inhabitants of seawater and even freshwater. Most organisms over 15% salts were halophilic. The salt concentrations comprised two ranges, each characterized by different microbial populations. First, between 15 and 30% salts, the populations ofDunaliella increased, reaching large numbers; moderately halophilic eubacteria and some fast-growing halobacteria predominated as heterotrophic microorganisms and, among the first, thePseudomonas-Alteromonas-Alcaligenes group andVibrio were the more abundant taxonomic groups; and gram-positive cocci appeared mainly over 25% salts. Phototrophic bacteria, both oxygenic and anoxygenic, were also found in this range, and among the anoxygenic type,Chromatium species andRodospirillum salexigens were probably predominant. Second, over 30% salts the diversity decreased greatly, all organisms found at the lower salt concentrations disappeared, and instead large populations of halobacteria developed. Over 50% salts, only three species of halobacteria were found.