Moose in Utah represent the southernmost naturally occurring populations of moose in the world. Concerns over possible numeric declines and a paucity of baseline data on moose in the state prompted the Utah Division of Wildlife Resources to initiate a study of moose demography in collaboration with Utah State University. The objectives of this study were to 1) determine reproductive rates of moose in Utah and the factors which influence them, and 2) combine aerial count data from multiple management units within the state to identify factors which influence interannual variation in population growth rates. We constructed generalized linear models to relate maternal body condition and age to reproductive success. We found that body condition (P = 0.01) and age (P = 0.02) contributed significantly to the probability of pregnancy and the best model describing this relationship was nonlinear. Body condition also related positively to subsequent calving (P = 0.08) and recruitment (P = 0.05), but model selection suggested the relationship for these metrics was best described by linear models. A meta-analysis of moose reproductive rates in North America suggested that reproductive rates declined significantly with latitude (P ≤ 0.01), i.e. as populations approached their southern range limit. We used Bayesian state-space models to combine moose count data from different management units to estimate statewide population dynamics between 1958 and 2013. This approach incorporated uncertainty in population counts arising from observation error. Population density and warm winter temperatures negatively influenced population growth rate with a high degree of confidence; 95% Bayesian Credible Intervals for these variables did not overlap zero. Short-term projections of moose abundance in the state suggested that the population will likely remain stable despite projected increases in winter temperature. Results from this study will aid managers in achieving management objectives as well as future decision making. The unique characteristics of the population also have application toward understanding the dynamics of populations of cold-adapted species at their southern range limit.

Flowering plants display diverse reproductive systems, including a variety of gender strategies and mechanisms of clonal propagation. Here, I investigate gender strategies, sex-ratio evolution, and sexual dimorphism in the North American clonal aquatic, Sagittaria latifolia (Alismataceae), which exhibits three sex phenotypes (hermaphrodites, females, males) and two modal sexual systems (monoecy, dioecy). This provides an outstanding opportunity to examine the costs and benefits of combined versus separate sexes. My research focused on the northern range limit in eastern N. America, and on disjunct populations in western N. America. I developed microsatellite (SSR) markers to investigate population genetic structure at several spatial scales, including the clonal structure of local populations to continental patterns. These analyses provided insights on the roles of historical, ecological and reproductive factors in the evolution and maintenance of sexual system diversity. Phenotypic sex ratios varied near continuously from monoecy through subdioecy (three sex phenotypes) to dioecy. A comparison of phenotypic and genotypic sex ratios in dioecious populations demonstrated close correspondence. The northern range limit was characterized by a decline in female frequency and an increased incidence of subdioecy. I evaluated two hypotheses to explain this pattern: (1) increased sex inconstancy in dioecious populations; (2) hybridization between monoecious and dioecious populations. I found support for both hypotheses, although hybridization appears to be the more common pathway to subdioecy. I parameterized a model predicting female frequency and hermaphrodite sex allocation; observed and predicted values were correlated suggesting that subdioecious populations are closer to equilibrium than expected for a clonal perennial. A comparison of eastern and western populations indicated genetic differentiation between monoecy and dioecy in the east, but in the west, due to habitat isolation, geography plays a more important role in genetic differentiation. Evidence from cpDNA haplotype variation indicated that the western range was established following long-distance colonization from the east involving a genetic bottleneck. The discovery of gynodioecious populations of S. latifolia in the west, and the absence of ecological and genetic differentiation between monoecious and dioecious populations, raise the possibility that dioecy may have evolved autochthonously in the west, and more recently than in the eastern range.

Flowering plants display diverse reproductive systems, including a variety of gender strategies and mechanisms of clonal propagation. Here, I investigate gender strategies, sex-ratio evolution, and sexual dimorphism in the North American clonal aquatic, Sagittaria latifolia (Alismataceae), which exhibits three sex phenotypes (hermaphrodites, females, males) and two modal sexual systems (monoecy, dioecy). This provides an outstanding opportunity to examine the costs and benefits of combined versus separate sexes. My research focused on the northern range limit in eastern N. America, and on disjunct populations in western N. America. I developed microsatellite (SSR) markers to investigate population genetic structure at several spatial scales, including the clonal structure of local populations to continental patterns. These analyses provided insights on the roles of historical, ecological and reproductive factors in the evolution and maintenance of sexual system diversity. Phenotypic sex ratios varied near continuously from monoecy through subdioecy (three sex phenotypes) to dioecy. A comparison of phenotypic and genotypic sex ratios in dioecious populations demonstrated close correspondence. The northern range limit was characterized by a decline in female frequency and an increased incidence of subdioecy. I evaluated two hypotheses to explain this pattern: (1) increased sex inconstancy in dioecious populations; (2) hybridization between monoecious and dioecious populations. I found support for both hypotheses, although hybridization appears to be the more common pathway to subdioecy. I parameterized a model predicting female frequency and hermaphrodite sex allocation; observed and predicted values were correlated suggesting that subdioecious populations are closer to equilibrium than expected for a clonal perennial. A comparison of eastern and western populations indicated genetic differentiation between monoecy and dioecy in the east, but in the west, due to habitat isolation, geography plays a more important role in genetic differentiation. Evidence from cpDNA haplotype variation indicated that the western range was established following long-distance colonization from the east involving a genetic bottleneck. The discovery of gynodioecious populations of S. latifolia in the west, and the absence of ecological and genetic differentiation between monoecious and dioecious populations, raise the possibility that dioecy may have evolved autochthonously in the west, and more recently than in the eastern range.

Magister Scientiae - MSc (Chemistry) / Pollutants such as polycyclic aromatic hydrocarbons (PAHs) are known for their toxic effects which may lead to the cause of degenerative diseases in both humans and animals. PAHs are widespread in the environment, and may be found in water, food, automotive industry and petrochemical industries to name but a few sources. Literature reports have highlighted industrial workplace exposure to PAHs as a leading cause for development of cancer in workers. Particularly, workers in the petrochemical industry are adversely affected and the incidence of skin and lung cancer in this population group is high. The United States of America in its guidelines developed by environmental protection agency (EPA) has identified 18 PAHs as priority pollutants. Among these are anthracene, benzo[a]pyrene and pyrene which have been selected as the focal point of this study due to their significance in the petrochemical industry. Due to the carcinogenic and mutagenic properties reported in literature for certain PAHs, there have been monitoring procedures taken in most countries around the world. The commonly used analytical methods for the detection of PAHs from industrial samples are high performance liquid chromatography (HPLC) coupled to fluorescence detection, membrane filtration, ozonation and reverse osmosis. Analysis of PAHs from the petrochemical industry is typically performed by HPLC method as well as sono-degredation in the presence of oxygen and hydrogen peroxide.