A 1998 study of interstitial fluid geochemistry within Charonis Cascade in the Echo River/River S... more A 1998 study of interstitial fluid geochemistry within Charonis Cascade in the Echo River/River Styx area of the Mammoth Cave System found carbon dioxide pressures higher than that of the fluids of the cave stream itself. This was confirmed by a limestone weight loss experiment in which samples dissolved at various levels below the streambed despite the low fluid velocities. The high CO2 pressures appear to influence both conduit dissolution rates and geometry and presumably result from the microbial degradation of organics within the sediments. To explore the relationship between the geochemical environment of fluids and microbial ecology, additional samples were collected from the same location. Eight Coliform bacteria were identified to species level and inoculated in 65 milliliters of thioglycollate broth along with a calcite crystal of known weight and incubated at 12°C for 92 days. In the presence of five of the bacterial species, calcite dissolved more than the control, rangi...
The field of molecular fecal source tracking in the water environment has developed rapidly since... more The field of molecular fecal source tracking in the water environment has developed rapidly since the first PCR assays for general and host-‐specific Bacteroides 16s rRNA markers were published. Numerous host-‐specific molecular markers and PCR assays have been developed, adding greater specificity, sensitivity and quantitative methods to the array of options. The public demand for readying methods for transfer to the commercial lab, so that they may be used to generate data for public utilities, citizen action groups and regulatory agencies, has fueled the development of an entire new research community. These methods, however plentiful, have not found community agreement and there is no consensus concerning the appropriate implementation of molecular fecal source tracking in the field. Some issues plaguing the implementation include imperfect marker specificity, environmental variability, DNA extraction variability, PCR inhibition and high cost of molecular analysis. This thesis...
A 1998 study of interstitial fluid geochemistry within Charonis Cascade in the Echo River/River S... more A 1998 study of interstitial fluid geochemistry within Charonis Cascade in the Echo River/River Styx area of the Mammoth Cave System found carbon dioxide pressures higher than that of the fluids of the cave stream itself. This was confirmed by a limestone weight loss experiment in which samples dissolved at various levels below the streambed despite the low fluid velocities. The high CO2 pressures appear to influence both conduit dissolution rates and geometry and presumably result from the microbial degradation of organics within the sediments. To explore the relationship between the geochemical environment of fluids and microbial ecology, additional samples were collected from the same location. Eight Coliform bacteria were identified to species level and inoculated in 65 milliliters of thioglycollate broth along with a calcite crystal of known weight and incubated at 12°C for 92 days. In the presence of five of the bacterial species, calcite dissolved more than the control, rangi...
The field of molecular fecal source tracking in the water environment has developed rapidly since... more The field of molecular fecal source tracking in the water environment has developed rapidly since the first PCR assays for general and host-‐specific Bacteroides 16s rRNA markers were published. Numerous host-‐specific molecular markers and PCR assays have been developed, adding greater specificity, sensitivity and quantitative methods to the array of options. The public demand for readying methods for transfer to the commercial lab, so that they may be used to generate data for public utilities, citizen action groups and regulatory agencies, has fueled the development of an entire new research community. These methods, however plentiful, have not found community agreement and there is no consensus concerning the appropriate implementation of molecular fecal source tracking in the field. Some issues plaguing the implementation include imperfect marker specificity, environmental variability, DNA extraction variability, PCR inhibition and high cost of molecular analysis. This thesis...
Uploads
Papers by Tricia Coakley