Anhydrophilic, Halotolerant Microbial Mats of San Salvador, Bahamas

Introduction

We have received funding from the National Science Foundation to establish a Microbial Observatory for the island of San Salvador, Bahamas. Similar to many Bahamian Islands, San Salvador Island contains numerous hypersaline (45 to 200 ‰) lakes and ponds. The lakes are subject to intense irradiance (µE m-2 s-1), high temperatures (> 30° C) and chronic nutrient depletion. Highly productive microbial mats blanket the shallow sediments in many of the lakes. In addition to the osmotic stress induced by the hypersaline conditions, large areas of the mats are subjected to an additional water stress, desiccation, as lake levels recede during the dry season (December to April). One of our primary goals is to isolate and characterize anhydrophilic microorganisms from the mats and lakes. The mats contain a rich diversity of microorganisms (click here to see organisms). Many are organisms found in mats throughout the world. However, the relative isolation of San Salvador, the extreme conditions, and diversity of organisms increases the likelihood that novel organisms possessing unique adaptive mechanisms inhabit the mats and lakes. The overall research objective of this study will be to assess the influence water availability has on structural diversification, community composition, production, and carbon sequestration in microbial mats.