Contrasting microbial community assembly hypotheses: a reconciling tale from the Río Tinto.
BACKGROUND
The Río Tinto (RT) is distinguished from other acid mine drainage systems by its natural and ancient origins. Microbial life from all three domains flourishes in this ecosystem, but bacteria dominate metabolic processes that perpetuate environmental extremes. While the patchy geochemistry of the RT likely influences the dynamics of bacterial populations, demonstrating which environmental variables shape microbial diversity and unveiling the mechanisms underlying observed patterns, remain major challenges in microbial ecology whose answers rely upon detailed assessments of community structures coupled with fine-scale measurements of physico-chemical parameters.


RESULTS
By using high-throughput environmental tag sequencing we achieved saturation of richness estimators for the first time in the RT. We found that environmental factors dictate the distribution of the most abundant taxa in this system, but stochastic niche differentiation processes, such as mutation and dispersal, also contribute to observed diversity patterns.


CONCLUSIONS
We predict that studies providing clues to the evolutionary and ecological processes underlying microbial distributions will reconcile the ongoing debate between the Baas Becking vs. Hubbell community assembly hypotheses.
Palacios
Carmen
C
The Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA, USA.
Zettler
Erik
E
Amils
Ricardo
R
Amaral-Zettler
Linda
L
D001419:Bacteria / Q000145:classification / Q000254:growth & development; D044822:Biodiversity; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000032:analysis; D017753:Ecosystem; D045483:Rivers / Q000382:microbiology*; D014871:Water Microbiology
D004269:DNA, Bacterial