Background.

Evaporitic environments are extreme habitats due to the combined effects of several environmental factors such as temperature and salinity, despite, their host a great diversity of prokaryotes, most poorly studied but with a great biotechnological potential. The Vizcaíno region in Northwestern Mexico represents an ideal area for the exploration of saline environments that result from their geological and contemporary history, particularly, the salty ponds known as “Las Charcas” represent an ideal model due to the null anthropogenic activity.

Goal.

To explore the factors that determine the structure community of bacteria and archaea residing in sediments with different levels of salinity.

Methods.

Six different ponds were sampled during January of 2018, after it, a fragment of 16S rRNA was amplified and sequenced using NGS. Alpha and beta diversity indices were estimated, on the other hand, Webb’s NTI and NRI metrics were used to evaluate which factors determine the phylogenetic community structures in each pond, finally, to evaluate which taxa are driven by selective pressures, a neutral test model was performed.

Results.

Diversity levels showed a positive correlation with salinity and organic matter, however, none of the biogeochemical parameters evaluated explained significantly the differences in composition among sampled ponds.

Conclusions.

The microbial structure community in the sediments of the ponds analysed is shaped by both deterministic and stochastic processes, including homogeneous selection, dispersal and ecological drift.