Soybean aphid, Aphis glycines Matsumura, is an important pest of North American soybean. This dissertation identifies and addresses knowledge gaps, and integrates existing knowledge regarding distribution and abundance of this species. Early summer soybean colonization patterns by A. glycines were examined relative to landscape parameters, including density of overwintering hosts (buckthorn). An information-theoretic model selection approach was used to determine which landscape parameters were most influential in the distribution of colonizing aphids. Though buckthorn abundance best explained aphid colonization and population density, a density-dependent effect was observed. When aphid populations were low, more aphids were found in the vicinity of buckthorn, when aphid populations were higher, more aphids were found farther from buckthorn. Suction trap captures of migrating populations of A. glycines from 2005-2009 from a suction trap network covering much of central North America were examined. A model selection approach was used to determine the environmental triggers of summer and fall aphid flights, and spatial analysis and modeled wind trajectories were used to examine patterns in the abundance of alates. Two alate activity peaks were observed in fall. In summer, formation of alates was a function of field infestation. A tritrophic population model was built using DYMEX, a mechanistic lifecycle based modeling software package. The model incorporated soybean, A. glycines, and three natural enemy species, interacting based on phenological, physiological and functional response data available in the literature. The model was validated using Ontario field data, and several simulations were performed and are discussed. An evaluation of proposed control strategies for efficacy and impact on natural enemies and the environment was conducted. Two novel concepts are presented: the natural enemy unit, a standardization of the impact of predator guild on prey populations by the number of prey an individual predator can eat, and the selectivity index, where the selectivity of a pesticide is a function of the change in ratio of natural enemy units to prey before and after treatment. The selectivity index was inversely correlated with the Environmental Impact Quotient (EIQ), a theoretical measure of impact, validating EIQ's field applicability. / Natural Sciences and Engineering Research Council of Canada; The Keefer family trust; the Mary Edmunds Williams trust, the family of Fred W. Presant, and the University of Guelph provided scholarship and fellowship funds. Research was funded by a grant to Rebecca Hallett and Art Schaafsma from the Agriculture and Agri-Food Canada Pest Management Centre’s Pesticide Risk Reduction Program.

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Through the years, there has been a great deal of archaeological research focused on the earliest farming cultures of Europe (i.e. Early Neolithic). However, little effort has been expended to uncover the type and nature of daily activities performed within Early Neolithic dwellings, particularly in the Balkans. This thesis conducts a spatial analysis of the Early Neolithic pit house levels of the Foeni-Salaş site in southeast Romania, in the northern half of the Balkans, to determine the kinds and locations of activities that occurred in these pit houses. Characteristic Early Neolithic dwellings in the northern Balkans are pit houses. The data are analyzed using Geographic Information Systems (GIS) technology in an attempt to identify non-random patterns that will indicate how the pit house inhabitants used their space. Both visual and statistical (Nearest Neighbor) techniques are used to identify spatial patterns. Spreadsheet data are incorporated into the map database in order to compare and contrast the results from the two techniques of analysis. Map data provides precise artefact locations, while spreadsheet data yield more generalized quad centroid information. Unlike the mapped data, the spreadsheet data also included artefacts recovered in sieves. Utilizing both data types gave a more complexand fuller understanding of how space was used at Foeni-Salaş. The results show that different types of activity areas are present within each of the pit houses. Comparison of interior to exterior artifact distributions demonstrates that most activities take place within pit house. Some of the activities present include weaving, food preparation, butchering, hide processing, pottery making, ritual, and other activities related to the running of households. It was found that these activities are placed in specific locations relative to features within the pit house and the physical structure of the pit house itself. This research adds to the growing body of archaeological research that implements GIS to answer questions and solve problems related to the spatial dimension of human behaviour.

Invasive exotic plant species have been recognized as serious threats to ecosystems. Extensive research on invasive exotic plant species has primarily focused on the impacts, characteristics, and potential treatments. Decision tools and management models that incorporate these findings often lack input from managers and have limited use in differing invasion scenarios. Therefore, in this study, I created a scientifically-driven framework that incorporates expert input to prioritize watersheds for management within the Inner Bluegrass region of Kentucky. The widely distributed invasive exotic plant Amur honeysuckle (Lonicera maackii) was used as an example species. The framework is built around the Analytic Hierarchy Process and highlights areas in most need of invasive exotic plant management by incorporating weighted landscape variables associated with the invasion process. Results of the prioritization provide useful information for natural resource managers by aiding in the development of control strategies while also creating a valuable framework that can be adapted to various invasive exotic plant species.

South Africa is a megadiverse country, and its biodiversity is endangered by population pressure and the development needs of a developing country. In order to address the rapid decline in biological diversity, biodiversity planning has become a key focus area that aims at identifying priority areas for species and ecosystem conservation within and outside of formally protected areas. Plant conservation hotspots are identified by the quantification of indicator taxa such as plant taxa richness, rarity and endemism. But the urgent and enormous task of biodiversity assessment for conservation planning requires that we make most of what we know. Therefore, this study seeks to make a contribution by finding new ways of biodiversity pattern estimation from the extrapolation of incomplete sets of plant species distribution data at the Quarter Degree Grid level. Incomplete sampling across the grids of a study area results in false records of species absence and thus a biased biodiversity estimation. As a possible solution, plant distribution data for the western Central Bushveld Bioregion has been standardized using two profiles, namely the ‘Centroid Grid’ and ‘Integrated Grid’ profile. The former involves the strengthening of under-sampled grids by extrapolating species occurrences from three adjacent grids with the most similar vegetation units, whereas the latter integrates phyto-diversity data for the four grids intersecting at each grid reference point. Standardized data has proved to provide a means to counter the bias in plant diversity data linked to Quarter Degree Grids by a) strengthening of under-sampled grids and b) visibly smoothing out the gaps between under- and well-sampled grids, which resulted in improved biodiversity estimation for more representative spatial biodiversity modelling. Interpolation created geo-referenced polygons for more explicit use in the identification of areas of conservation concern at bioregional scale. However, well-sampled grids still dominate the outcomes of the analysis by creating spatial sampling bias. Therefore, this approach to calibrate Quarter Degree Grid resolution of spatial data is an additional attempt to achieve more representative mapping of biodiversity patterns, which is a prerequisite for strategic conservation planning for ‘living landscapes’. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2012

South Africa is a megadiverse country, and its biodiversity is endangered by population pressure and the development needs of a developing country. In order to address the rapid decline in biological diversity, biodiversity planning has become a key focus area that aims at identifying priority areas for species and ecosystem conservation within and outside of formally protected areas. Plant conservation hotspots are identified by the quantification of indicator taxa such as plant taxa richness, rarity and endemism. But the urgent and enormous task of biodiversity assessment for conservation planning requires that we make most of what we know. Therefore, this study seeks to make a contribution by finding new ways of biodiversity pattern estimation from the extrapolation of incomplete sets of plant species distribution data at the Quarter Degree Grid level. Incomplete sampling across the grids of a study area results in false records of species absence and thus a biased biodiversity estimation. As a possible solution, plant distribution data for the western Central Bushveld Bioregion has been standardized using two profiles, namely the ‘Centroid Grid’ and ‘Integrated Grid’ profile. The former involves the strengthening of under-sampled grids by extrapolating species occurrences from three adjacent grids with the most similar vegetation units, whereas the latter integrates phyto-diversity data for the four grids intersecting at each grid reference point. Standardized data has proved to provide a means to counter the bias in plant diversity data linked to Quarter Degree Grids by a) strengthening of under-sampled grids and b) visibly smoothing out the gaps between under- and well-sampled grids, which resulted in improved biodiversity estimation for more representative spatial biodiversity modelling. Interpolation created geo-referenced polygons for more explicit use in the identification of areas of conservation concern at bioregional scale. However, well-sampled grids still dominate the outcomes of the analysis by creating spatial sampling bias. Therefore, this approach to calibrate Quarter Degree Grid resolution of spatial data is an additional attempt to achieve more representative mapping of biodiversity patterns, which is a prerequisite for strategic conservation planning for ‘living landscapes’. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2012

A large portion of the freshwater in western Canada originates as snowpack from the northern Rocky Mountains. The temperature and precipitation in these areas controls the amount of snow accumulated and stored throughout the winter, and the amount and timing of melt that occurs during the spring freshet. Therefore, a better understanding of past and future changes to the extent of snowpack and timing of melt can modify the timing of peak river flow on a continental scale. Trends in temperature, precipitation, snow accumulation, and snowmelt are examined using the Mann-Kendall non-parametric test on a high resolution gridded climate dataset over western Canada for the period 1950-2010. In addition, projected changes in temperature, precipitation, snow water equivalent, and snowmelt are examined through comparison of the current (1971-2000) and future (2041-2070) time periods incorporating several regional climate models. The temporal and spatial analyses of these key hydroclimatic variables indicate that changes vary greatly over space and time. Results reveal that while both maximum and minimum temperature have increased in the past 60 years, minimum temperature has increased more than maximum temperature and is likely to continue doing so in the future. This trend is particularly evident during the colder months of the year, and at higher elevations, contributing to earlier spring melt. Between 1950 and 2010, precipitation has decreased throughout the colder months of the year and increased in the warmer months, particularly in the northern half of the study area. Future projections show increased precipitation, specifically in the north. Throughout the historical period snow accumulation has experienced decreases across the study area and through all months of the year, except for increases at high elevations. In the coldest months of the year snow accumulation is projected to increase in high elevation and northern areas while decreasing across the rest of study area in the future. Snowmelt results indicate slight increases in mid-winter melt events and an earlier onset of the spring freshet; this change is expected to continue into the future period. This study provides a summary of detected trends and potential future changes in key hydroclimatic variables across western Canada with regard to the effects these changes can have on the spring freshet and streamflow, and thus water resources, throughout the study area. / Graduate / 0368

Through the years, there has been a great deal of archaeological research focused on the earliest farming cultures of Europe (i.e. Early Neolithic). However, little effort has been expended to uncover the type and nature of daily activities performed within Early Neolithic dwellings, particularly in the Balkans. This thesis conducts a spatial analysis of the Early Neolithic pit house levels of the Foeni-Salaş site in southeast Romania, in the northern half of the Balkans, to determine the kinds and locations of activities that occurred in these pit houses. Characteristic Early Neolithic dwellings in the northern Balkans are pit houses. The data are analyzed using Geographic Information Systems (GIS) technology in an attempt to identify non-random patterns that will indicate how the pit house inhabitants used their space. Both visual and statistical (Nearest Neighbor) techniques are used to identify spatial patterns. Spreadsheet data are incorporated into the map database in order to compare and contrast the results from the two techniques of analysis. Map data provides precise artefact locations, while spreadsheet data yield more generalized quad centroid information. Unlike the mapped data, the spreadsheet data also included artefacts recovered in sieves. Utilizing both data types gave a more complexand fuller understanding of how space was used at Foeni-Salaş. The results show that different types of activity areas are present within each of the pit houses. Comparison of interior to exterior artifact distributions demonstrates that most activities take place within pit house. Some of the activities present include weaving, food preparation, butchering, hide processing, pottery making, ritual, and other activities related to the running of households. It was found that these activities are placed in specific locations relative to features within the pit house and the physical structure of the pit house itself. This research adds to the growing body of archaeological research that implements GIS to answer questions and solve problems related to the spatial dimension of human behaviour.

Sharing and inappropriate discarding of syringes and drug use equipment can lead to transmission of bloodborne pathogens and decreased sense of community safety. To reduce these risks, interventions such as syringe drop boxes, are implemented. However, little consideration has been made of the social and spatial networks of the injection drug use (IDU) populations in the placement of these drop boxes. A sample of IDU was obtained through respondent driven sampling in Winnipeg, Canada in 2009. Characteristics of the sample and distribution of these characteristics through the social network were assessed. A spatial network was constructed which focused on the connections between IDU and specific geographic locations. Measures of centrality were calculated using Pajek and the geographic network was mapped using ArcGIS. Analysis of the social network revealed variation among network components in demographic and drug use characteristics. Spatial analysis revealed geographic clustering, quantified through network centrality measures. There was congruence between locations of high degree and current drop box placement in Winnipeg. This research illustrates the benefit of combining IDU social network and spatial data to inform evidence-based municipal policies and programs.

Acute Myocardial Infarction (AMI), commonly known as heart attack, is a leading cause of death for adult men and women in the world. Studying mortality after AMI is therefore an important problem in epidemiology. This thesis develops statistical methodology for examining geographic patterns in mortality following AMI. Specifically, we develop parametric Accelerated Failure Time (AFT) models for censored survival data, where space-varying regression is used to investigate spatial patterns of mortality after AMI. In addition to important covariates such as age and gender, the regression models proposed here also incorporate spatial random e ects that describe the residual heterogeneity associated with di erent local health geographical units. We conduct model inference under a hierarchical Bayesian modeling framework using Markov Chain Monte Carlo algorithms for implementation. We compare an array of models and address the goodness-of- t of the parametric AFT model through simulation studies and an application to a longitudinal AMI study in Quebec. The application of our AFT model to the Quebec AMI data yields interesting ndings concerning aspects of AMI, including spatial variability. This example serves as a strong case for considering the parametric AFT model developed here as a useful tool for the analysis of spatially correlated survival data.