Research

 

II. Microbial Communities and Activities in Oligotrophic Environments - Caves

 

Figure 1 Figure 2   Kartchner Caverns in Benson, Arizona is a beautiful example of carbonate cave development and is one of the top ten caves in the world in terms of mineralogical and speleothem diversity. Unfortunately, fundamental data on microbial communities within this cave, and for cave systems in general, is lacking. This is a significant deficiency and a major impediment to continued scientific research and education on oligotrophic environments such as caves, and to sustainable public development of these unique and delicate ecosystems. Systematic studies are urgently needed to more precisely define cave microbial community structure and resolve fundamental questions regarding the influence of physical, chemical, and biological factors on community stability.

(Above) Five Swab Samples were obtained along the vertical axis of this speleothem

 

(Left) Julie Neilson taking a swab sample of a speleothem

In this project we are:

  1. defining microbial communities recovered from varied substrata in Kartchner Caverns using multivariate analysis of DGGE community profiles and phylogenetic analysis of microbial DNA sequences
  2. conducting metagenomic analysis of specific speleothem and other communities
  3. contrasting microbial diversity based on defined carbon gradients, and
  4. analyzing biosurfactants produced by speleothem-associated bacteria and fungi, and incorporate their surface tension and liquid viscosity properties into modeling speleothem growth processes.

Embedded within these objectives are the additional goals of creating non-culturable (DNA) and culturable cave microbial libraries, and developing an on-line database for the dissemination of data generated from these and other related studies. These will serve as world-wide resources for the advancement of contemporary research on cave microbiology and be valuable tools in the global preservation of cave and cave formations.

 

 

Entrance to Kartchner Caverns State Park

 

(from left to right) Ginger Nolan, Julie Neilson, Marian Ortiz and Antje Legatzki after a hard day of sampling at Kartchner

(to go to Kartchner Caverns State Park Website, please click here)

 

To go to the NSF Kartchner Caverns Microbial Observatory Website, click here.

Project: Kartchner Caverns: Habitat-Scale Community Structure and Function in Carbonate Caves.

Funding Source: National Science Foundation Microbial Observatory Program.

Collaborators: Dr. Barry Pryor, Dr. Leland Pierson, Dr. Rod Wing, Dr. Craig Rasmussen, Dr. Jay Quade, Dr. Cari Soderlund, Dr. Jon Chorover.

Relevant Publications:

Ortiz, M., J.W. Neilson, W.M. Nelson, A. Legatzki, A. Byrne, Y. Yu, R.A. Wing, C.A. Soderlund, B.M. Pryor, L.S. Pierson III, and R.M. Maier. Variations in bacterial diversity and taxonomic composition on speleothem surfaces in Kartchner Caverns, AZ, in review.

Legatzki, A., M. Ortiz, J.W. Neilson, R.R. Casavant, M.W. Palmer, C. Rasmussen, B.M. Pryor, L.S. Pierson III, and R.M. Maier. 2012. Factors influencing the speleothem-specific structure of bacterial communities on the surface of formations in Kartchner Caverns, AZ, USA.  Geomicrobiol. J., 29:422-434.

Vaughan, M.J., R.M. Maier, and B.M. Pryor.  2011.  Fungal communities on speleothem surfaces in Kartchner Caverns, Arizona, USA.  Internat. J. Speleology, 40:65-77.

Legatzki, A., M. Ortiz, J.W. Neilson, S. Dominguez, G.L. Andersen, R.S. Toomey, B.M. Pryor, L.S. Pierson III, and R.M. Maier.  2011.  Bacterial and archaeal community structure of two adjacent calcite speleothems in Kartchner Caverns, Arizona, USA.  Geomicrobiol. J.  28:99-117.

Ikner, L.A., R.S. Toomey, G. Nolan, J.W. Neilson, B.M. Pryor, and R.M. Maier.  2007.  Cultural microbial diversity and the impact of tourism in Kartchner Caverns, Arizona.  Microbial Ecol.  53:30-42.