The Dallas-Fort Worth International (DFW) Airport is located in a densely urbanized area with one of the fastest-growing populations in the U.S.A. The airport property includes a large tract of "protected" riparian forest that is unique to the urban surroundings. This dissertation explores variables that influence the benthic macroinvertebrate community structure found in urbanized prairie streams that were initially assessed by the University of North Texas (UNT) Benthic Ecology Lab during four, non-consecutive biomonitoring studies (2004, 2005, 2008, and 2014) funded by the DFW Airport. Additionally, land use analysis was performed using 5-meter resolution satellite imagery and eCognition to characterize the imperviousness of the study area watersheds at multiple scales. Overall, flow conditions and imperviousness at the watershed scale explained the most variability in the benthic stream community. Chironomidae taxa made up 20-50% of stream communities and outperformed all other taxa groups in discriminating between sites of similar flows and urban impairments. This finding highlights the need for genus level identifications of the chironomid family, especially as the dominant taxa in urban prairie streams. Over the course of these biomonitoring survey events, normal flow conditions and flows associated with supra-seasonal drought were experienced. Prevailing drought conditions of 2014 did not …

The Trinity River flows through the Dallas-Ft. Worth Metroplex in north central Texas where it receives effluents from numerous point sources including seven large regional wastewater treatment facilities. Historically, the Trinity River has been impacted by massive wastewater loadings which often constitute > 80% of the total river discharge during low flow periods. Normally, high mass loadings correspond to the summer months, compounding the effects of a naturally stressful period, characterized by high temperatures and low dissolved oxygen concentrations. Samples from 12 stations were collected quarterly over an 18 month period from the Trinity River and two tributaries. Water samples were analyzed for a variety of water quality variables, including metals, priority pollutants, pesticides, and general water quality parameters. Water samples were also tested for acute and subchronic effects with several test species. Fish were collected at each station and assemblages were characterized using traditional classification techniques and the Index of Biotic Integrity. In addition, sediment samples were assessed for toxic effects which could have adversely impacted fish recruitment and in situ biomonitoring experiments were performed. Quantitative habitat characterization analyses were performed to gain additional information that could possibly explains differences in fish assemblage structure related to habitat variability. Data …