Research

Hypersaline Mats

Hypersaline Communities from Baja California

As part of a large scale, multidisciplinary effort to understand the complex interactions between microbial community structure and emergent ecosystem properties we are studying hypersaline microbial mats from Guerrero Negro in Baja California (México) as models of microbial ecosystems.

These photosynthetic communities are benthic, laminated aquatic biofilms consisting of highly structured, and dynamic communities of microorganisms. Hypersaline microbial mats harbor a large variety of organisms able to tolerate and thrive under environmental extreme conditions such as high salinity, light exposure and gases such as hydrogen sulfide and hydrogen.

We are particularly interested in explaining the distribution and abundance of these microorganisms in time and space in terms of environmental gradients and interactions. These microbial mats represent the modern analogs for what must have been the major type of ecosystem on Earth for much of its early history. Understanding their functioning gives us the key to understanding the past features of Earth’s biogechemistry.

: This is an example of a temporary pond at one of the natural lagoon sites.

: This is a close up view of the example seen in the previous picture.

: Microbial mats kept in open aquaria, exposed to normal diel and seasonal cycles of light intensity, temperature and water.

: Close up image of a surface of a mat, showing bubble formation.

: This is an example of the way microbial mat samples are taken from the field. Cores are taken from the mat (circular missing pieces). The top ~ 3 cm are removed and frozen in liquid nitrogen. The samples are then transported back to the lab where to study the community structure.

: This is an example of how the microbial mats affect the geomorphology of the area. The microbial mats consolidate and strengthen the soil, so when the high tide comes through the lagoon, the soil is not washed away, but forms these reef-like structures.