Cave microbial community composition in oceanic islands: disentangling the effect of different colored mats in diversity patterns of Azorean lava caves.

Processes determining diversity and composition of bacterial communities in island volcanic caves are still poorly understood. Here, we characterized colored microbial mats in 14 volcanic caves from two oceanic islands of the Azores using 16S rRNA gene sequences. Factors determining community diversity (α) and composition (β) were explored, namely colored mats, caves and islands, as well as environmental and chemical characteristics of caves.

Comparison of Bacterial Diversity in Azorean and Hawai'ian Lava Cave Microbial Mats.

Worldwide, lava caves host colorful microbial mats. However, little is known about the diversity of these microorganisms, or what role they may play in the subsurface ecosystem. White and yellow microbial mats were collected from four lava caves each on the Azorean island of Terceira and the Big Island of Hawai'i, to compare the bacterial diversity found in lava caves from two widely separated archipelagos in two different oceans at different latitudes.

Diversity of Ammonia Oxidation () and Nitrogen Fixation () Genes in Lava Caves of Terceira, Azores, Portugal.

Lava caves are an understudied ecosystem in the subterranean world, particularly in regard to nitrogen cycling. The diversity of ammonia oxidation () and nitrogen fixation () genes in bacterial mats collected from lava cave walls on the island of Terceira (Azores, Portugal) was investigated using denaturing gradient gel electrophoresis (DGGE). A total of 55 samples were collected from 11 lava caves that were selected with regard to surface land use.