Masters Theses


"This research is geared toward contributing to existing knowledge of the in-situ degradation of aromatic petroleum hydrocarbons such as benzene, toluene, ethylbenzene, and o, m, p-xylene (BTEX). While the degradation of these types of contaminants has been widely studied in the past, limited knowledge exists on the degradation of these contaminants with phytoremediation using Populus deltoides x Populus nigra, clone #34 (DN34). This study proposes to answer the following questions:

  • Does the natural water cycling induced by the DN34 enhance BTEX degradation?
  • Does the DN34 increase the BTEX degrading population of microorganisms?
  • Does the natural water cycling induced by the DN34 increase the BTEX degrading population of microorganisms?
  • Does the presence of BTEX increase the BTEX degrading population of microorganisms?

Methods include the use of the most probable number (MPN) technique to enumerate both the heterotrophic and BTEX degrading population of organisms in the root zone of the DN34 while monitoring the degradation of spiked amounts of BTEX with a gas chromatograph-flame ionization detector. Analysis of the data suggests that the groundwater drawdown caused by the DN34 does influence the total microbial population. Additionally, the availability of BTEX can increase BTEX degrading populations. There does not seem to be any correlation between the population of BTEX degraders and depth within the experimental columns. Analysis of the GC data suggests that BTEX may have been more readily degraded in the upper, more aerated levels of the column. The limitation of the lines of evidence supporting the hypothesis is largely due to the fact that the experiment was run over too short of a period of time and at a suboptimal time of year. Although there is a fair amount of evidence that suggests that the natural water cycling induced by the DN34 enhances BTEX degradation, it is recommended that further research be conducted in order to more precisely identify the beneficial nature of the DN34 and its effect on contaminant removal from the subsurface"--Abstract, page iii.


Mormile, Melanie R.
Burken, Joel G. (Joel Gerard)

Committee Member(s)

Maglia, Anne M.


Biological Sciences

Degree Name

M.S. in Applied and Environmental Biology


University of Missouri--Rolla

Publication Date

Summer 2007


ix, 178 pages

Note about bibliography

Includes bibliographical references (pages 175-177).


© 2007 Andrew Gabriel Jugan, All rights reserved.

Document Type

Thesis - Restricted Access

File Type




Subject Headings

Hydrocarbons -- Biodegradation
Petroleum chemicals -- Biodegradation

Thesis Number

T 9231

Print OCLC #


Electronic OCLC #


Link to Catalog Record

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