This research analyzed the spatial relationship between a mega-scale fracture network and the occurrence of vegetation in an arid region. High-resolution aerial photographs of Arches National Park, Utah were used for digital image processing. Four sets of large-scale joints were digitized from the rectified color photograph in order to characterize the geospatial properties of the fracture network with the aid of a Geographic Information System. An unsupervised landcover classification was carried out to identify the spatial distribution of vegetation on the fractured outcrop. Results of this study confirm that the WNW-ESE alignment of vegetation is dominantly controlled by the spatial distribution of the systematic joint set, which in turn parallels the regional fold axis. This research provides insight into the spatial heterogeneity inherent to fracture networks, as well as the effects of jointing on the distribution of surface vegetation in desert environments.

The objective of this study was to develop a GIS-based multi-class index overlay model to determine areas susceptible to inland flooding during extreme precipitation events in Broward County, Florida. Data layers used in the method include Airborne Laser Terrain Mapper (ALTM) elevation data, excess precipitation depth determined through performing a Soil Conservation Service (SCS) Curve Number (CN) analysis, and the slope of the terrain. The method includes a calibration procedure that uses "weights and scores" criteria obtained from Hurricane Irene (1999) records, a reported 100-year precipitation event, Doppler radar data and documented flooding locations. Results are displayed in maps of Eastern Broward County depicting types of flooding scenarios for a 100-year, 24-hour storm based on the soil saturation conditions. As expected the results of the multi-class index overlay analysis showed that an increase for the potential of inland flooding could be expected when a higher antecedent moisture condition is experienced. The proposed method proves to have some potential as a predictive tool for flooding susceptibility based on a relatively simple approach.

<p>Soil water repellency is a spatially and temporally variable near surface phenomenon most often associated with reduced or impeded infiltration into porous media. In recent years, soil water repellency (hydrophobicity) has garnered much attention in the literature due to its detrimental effects on soil water processes and its widespread observance allover the world in both rural and urban settings. While previous work has developed our understanding of these inherently complex systems, insight into their dynamic and variable nature is still lacking. Having utilized existing technologies in a new way, in this study we present a series of systematic field and laboratory based investigations that clarify the roles of fractional wetting and contact angle dynamics on soil water processes using hydrophobic materials found at a wildfire site approximately 1.5 years post-fire. The robust and fundamental approach taken in investigating<br />water repellency in these materials provided the foundation to develop two conceptual models based on our observations and with respect to existing and emerging theory. These models better explain soil water behaviour in hydrophobic systems than is currently afforded by the literature. We found that wetting and infiltration processes are contingent upon the functional relationship between wettable fractions of materials and the rate of contact angle change in non-wettable fractions.</p> / Master of Science (MS)

Ozone readings which exceeded the National Ambient Air Quality Standard of 120 ppbv were recorded in Miami, Florida during 1978 and 1980. Similar elevated concentrations of ozone extended across upper Florida and into the Southeastern portion of the United States. It is concluded that tropospheric transport of ozone into the Miami area occurs. This conclusion is supported by lead analyses of atmospheric samples taken in Miami and by isentropic trajectories. Six case studies are presented. In all cases transport of ozone into Florida appears to occur. In only four of the cases does this result in elevated ozone levels in Miami. In one case lower Florida was experiencing an oceanic influx of air and low ozone concentrations. In the other case Miami was experiencing a stagnation and high ozone concentrations apparently generated locally. The long range transport of ozone across the Southeastern United States appears to result from circulation within a weather pattern characterized by a stagnant high pressure system over the Southeastern United States.

Small warm-water streams in the southeastern United States experience significant differences in temperature, as well as changes in physical parameters due to seasonal fluctuations. It has been generally thought that fish assemblage patterns change as a direct result of these seasonal variations. This study was designed to determine the effects of variable flow regimes on fish species composition, diversity, and abundance. Eight small warm-water streams in four national parks (Chickamauga and Chattanooga National Military Park, Fort Donelson National Battlefield, Abraham Lincoln Birthplace National Historic Site, and Russell Cave National Monument) were sampled May-June 2005 for the summer trials, October-November 2005 for the fall trials, and April 2006 for the spring trials. All trials were conducted when water levels and flows were at normal seasonal stages. Fish populations were determined by electrofishing a 100-m reach at each site. Physical parameters including temperature, dissolved oxygen, conductivity, pH, and flow rate were also measured at each site. From summer to fall, the majority of the streams decreased in flow until temporary pools were formed. The lack of flow caused increased temperatures, decreased dissolved oxygen, and increased conductivity levels. As a direct result, overall fish abundance and diversity values decreased. From fall to spring, all the streams increased in flow, which brought back the riffle to pool habitat sequences. Dissolved oxygen levels increased, conductivity levels decreased, and temperatures became more stable. As a result, overall fish abundance and diversity values increased. Results indicated that fish assemblage patterns in the four parks did change as a direct result of the seasonal variations in habitat and water quality.

Since a young age, I have been interested in bicycling as a form of fun and fanciful recreation, but it wasn’t until the summer of 2011 that a serious shift occurred in my understanding of the bike as more than a mere machine. A spontaneous 700-mile journey redefined my relationship with travel, transcended my notions of transportation, and enabled me to better mediate myself within my environment. In writing about these experiences, I hope to offer some insight into how American culture currently frames transportation and how I hope the construction of a bike positive culture can instill social, environmental, and political change. Concurrently, I created a pin-up style bicycle calendar featuring enthusiasts from the Claremont Colleges to foster a sense of community around bicycling and inspire riders and non-riders alike to further explore their ‘bicyxuality’. Intermingling this nonfiction piece with a thoughtful reflection on the BIKEurious calendar project, this paper serves to explain my creative undertakings and, ultimately, call into question the hierarchy of transportation in America today.

Small warm-water streams in the southeastern United States experience significant differences in temperature, as well as changes in physical parameters due to seasonal fluctuations. It has been generally thought that fish assemblage patterns change as a direct result of these seasonal variations. This study was designed to determine the effects of variable flow regimes on fish species composition, diversity, and abundance. Eight small warm-water streams in four national parks (Chickamauga and Chattanooga National Military Park, Fort Donelson National Battlefield, Abraham Lincoln Birthplace National Historic Site, and Russell Cave National Monument) were sampled May-June 2005 for the summer trials, October-November 2005 for the fall trials, and April 2006 for the spring trials. All trials were conducted when water levels and flows were at normal seasonal stages. Fish populations were determined by electrofishing a 100-m reach at each site. Physical parameters including temperature, dissolved oxygen, conductivity, pH, and flow rate were also measured at each site. From summer to fall, the majority of the streams decreased in flow until temporary pools were formed. The lack of flow caused increased temperatures, decreased dissolved oxygen, and increased conductivity levels. As a direct result, overall fish abundance and diversity values decreased. From fall to spring, all the streams increased in flow, which brought back the riffle to pool habitat sequences. Dissolved oxygen levels increased, conductivity levels decreased, and temperatures became more stable. As a result, overall fish abundance and diversity values increased. Results indicated that fish assemblage patterns in the four parks did change as a direct result of the seasonal variations in habitat and water quality.

Freshwater use is a major concern in the mass production of algae for biofuels. This project examined the use of canal water obtained from the Everglades Agricultural Area as a base medium for the mass production of algae. This water is not suitable for human consumption, and it is currently used for crop irrigation. A variety of canals were found to be suitable for water collection. Comparison of two methods for algal production showed no significant difference in biomass accumulation. It was discovered that synthetic reticulated foam can be used for algal biomass collection and harvest, and there is potential for its application in large-scale operations. Finally, it was determined that high alkaline conditions may help limit contaminants and competing organisms in growing algae cultures.

Tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire) has long been known as a turfgrass that utilizes lower levels of inputs than most other cool season turfgrasses (Turgeon, 2005). In recent years, turf breeders have been selecting for cultivars of tall fescue that have finer leaf textures. As the use of tall fescue expands, consumers want to now what cultivar to use and how to manage it. This study looked at 18 tall fescue cultivars grown at two mowing heights of five and 10 centimeters and evaluated plant quality based on stand density, leaf texture, and genetic plant color. In the first year of the study, although there were some differences, there were no continual patterns that proved one cultivar to be better or worst than the others. Lower mowing heights generally had higher stand density ratings and fertilization affected genetic plant color, not mowing height. There was no difference in leaf texture between mowing heights.

I analyzed lake fertilization (with nitrogen and phosphorus) as a tool to assist in the recovery of the Snake River sockeye salmon (Oncorhynchus ~) in the oligotrophic Sawtooth Valley Lakes in southcentral Idaho. These analyses involved monitoring, manipulating, and modelling several aspects of the lakes' primary producer, nutrient, and light parameters. In Pettit Lake, I evaluated the effects of metalimnetic and epilimnetic fertilization in 330-m 3 mesocosms. The metalimnetic treatment was equal to or more effective than the epilimnetic treatment in increasing chlorophyll a, phytoplankton biovolume, and primary productivity, yet caused smaller changes in periphyton growth and water clarity. Thus, metalirnnetic fertilization may provide a tool for increasing lake productivity while minimally impacting water clarity. The Sawtooth Valley Lakes had deep chlorophyll maxima (DCM) with mean chlorophyll a peaks 240-1000% of mean epilimnetic concentrations. The DCM existed at low light levels and accounted for 36- 72% of the lakes' primary production. Epilimnetic fertilization of330-m 3 mesocosms in Redfish Lake increased levels of primary productivity and chlorophyll a, but decreased Secchi depths and light available in the meta- and hypolimnion. I modelled the effects of increased chlorophyll (resulting from epilimnetic fertilization) and decreased light penetration on vertical primary productivity profiles. The simulations showed a large increase in epilimnetic primary productivity due to fertilization, and only a slight decrease in production in the deeper strata due to self-shading. I also modelled the dependence of Red fish Lake's production on nutrients from the watershed, from lake fertilization, and from marine-derived nutrients from salmon. The model utilized our water budget and nutrient loading measurements. The model and empirical evidence indicated that even before hydropower dams were present in the migration corridor, marine-derived nutrients were not of major importance to lake production, contributing only ~3% of the lake's annual phosphorus load. This contribution was partially offset by the lake's quick flushing rate (3 yr) and phosphorus export by smolts. The model predicted annual adult salmon returns to be 3,800 under pre-dam conditions, 370 under modern conditions, 750 when doubling watershed nutrient loading (simulating lake fertilization), and 780 when doubling migration survival.