Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1999. / Copies of author's previously published articles inserted. Bibliography: leaves 317-359.

Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1999? / Corrigenda pasted onto front end-paper. Bibliography: leaves 307-326.

Thesis (Ph. D.)--University of Adelaide, School of Civil and Environmental Engineering, 2006. / "October 2006." Includes bibliographical references (p. 261-270). Also available in print form.

Thesis (Ph. D.)--University of Washington, 1991. / Vita. Includes bibliographical references (leaves [162]-168).

Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 10, 2009). Includes bibliographical references.

Thesis (Ph.D)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2008. / Committee Chair: Nenes, Athanasios; Committee Co-Chair: Smith, Jim; Committee Member: Bergin, Mike; Committee Member: Huey, Greg; Committee Member: Weber, Rodney. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M.S.)--University of California, Santa Cruz, 1997. / Typescript. Includes bibliographical references (leaves 88-89).

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 114-119). Available also in an electronic version from UMI Company.

<p> I examined flow-ecology relationships among stream communities in the Ozark Highlands, USA. I sampled fish, crayfish, and benthic macroinvertebrates during two consecutive summers, including a drought year (2012) and a flood year (2013). Biological response variables related to community structure were assessed via two different statistical methods: an Information Theoretic approach relating response variables to <i>a priori</i> selected predictor variables incorporating hydrology, habitat, geomorphology, and water quality, and canonical ordination using forward selection to relate these same response variables to a large assortment of hydrologic metrics. In addition to assessing metrics related to predicted natural flow, flow alteration at gaged sites was also quantified and community metrics were assessed with respect to flow alteration. Additionally, I conducted a manipulative laboratory greenhouse experiment to examine the effects of stream drying, one of the major components of the natural hydrologic disturbance regime in the region, on stream fishes as well as benthic community structure. Hydrologic variation was often less important than other environmental variables and substantial temporal variation existed in flow-ecology relationships. Stream flow magnitude was the most important category of hydrologic metric overall, but there were key differences in which metrics were important for each assemblage and how those assemblages responded to those metrics. Flow alteration has a strong effect on Ozark riverine communities, and the most important categories of flow alteration affecting these communities are magnitude of average flows, and frequency, magnitude, and duration of high flows. The large number of important high flow metrics suggests that flood events may play a particularly crucial role in structuring aquatic assemblages in the region. I found that seasonal stream drying had strong species-specific effects on organisms in pool refuges, and that type of drying specifically affected periphyton growth. Overall, I found that the elucidation of flow-ecology relationships and management decisions that are based on those relationships face a variety of challenges: the complex interaction of hydrology with other kinds of environmental variables, temporal variation in the aquatic community, and the differential effects of flow metrics on different assemblages.</p>

Understanding the spatial and temporal dynamics occurring in headwater catchments enhances our ability to effectively manage the natural and unnatural inputs from the landscape to the stream. DOC is particularly important in northern peat dominated catchments, where concentrations in rivers have been increasing over recent decades. Due to the significant downstream impacts this increase has on the functioning of aquatic ecosystems and the quality of drinking water, it is vital to understand the tight coupling between the landscape and the stream. This study set out to explore the use of integrating high-frequency DOC data, stable isotopes and modelling as a novel way to increase our understanding of the hydrological and biogeochemical processes that control spatial and temporal DOC dynamics. By deploying in-situ FDOM sensors, across nested catchments, we captured 15 minute DOC dynamics. This yielded insights into seasonal, event and diel temporal variability, along with spatial variability. Results showed the utility of linking these DOC dynamics with stable isotopes and water ages, extracted from a tracer-aided runoff model. This allowed the main runoff generating processes, that transport the DOC from the sources to the stream, to be assessed, and showed the effects of hydrologic connectivity and antecedent conditions on DOC delivery. Incorporating modelling allowed the non-stationary hydrological processes influencing runoff generation, which cannot be easily measured by field techniques, to be evaluated. Overall, the findings of this thesis underline the utility of integrating highfrequency DOC data, stable isotopes and modelling to extract a highly informative dataset that helps produce a more complete symphony of the highly variable dynamics occurring in upland catchments. Such knowledge is crucial in order to effectively evaluate the influence of climate change on the water resources that both nature and humans so heavily depend on.