Methane- and dissolved organic carbon-fueled microbial loop supports a tropical subterranean estuary ecosystem.
D BrankovitsJohn W PohlmanHelge NiemannMary Beth LeighMary-Cathrine LeewisKevin W BeckerThomas M IliffeF AlvarezMoritz F LehmannB PhillipsPublished in: Nature communications (2017)
Subterranean estuaries extend inland into density-stratified coastal carbonate aquifers containing a surprising diversity of endemic animals (mostly crustaceans) within a highly oligotrophic habitat. How complex ecosystems (termed anchialine) thrive in this globally distributed, cryptic environment is poorly understood. Here, we demonstrate that a microbial loop shuttles methane and dissolved organic carbon (DOC) to higher trophic levels of the anchialine food web in the Yucatan Peninsula (Mexico). Methane and DOC production and consumption within the coastal groundwater correspond with a microbial community capable of methanotrophy, heterotrophy, and chemoautotrophy, based on characterization by 16S rRNA gene amplicon sequencing and respiratory quinone composition. Fatty acid and bulk stable carbon isotope values of cave-adapted shrimp suggest that carbon from methanotrophic bacteria comprises 21% of their diet, on average. These findings reveal a heretofore unrecognized subterranean methane sink and contribute to our understanding of the carbon cycle and ecosystem function of karst subterranean estuaries.
Keyphrases
- climate change
- microbial community
- human health
- anaerobic digestion
- antibiotic resistance genes
- carbon dioxide
- fatty acid
- organic matter
- risk assessment
- heavy metals
- genome wide
- single cell
- transcription factor
- physical activity
- weight loss
- copy number
- drinking water
- health risk
- dna methylation
- high resolution
- gene expression
- mass spectrometry