Doctor of Philosophy / Department of Biology / Keith B. Gido / Global climate change could lead to less frequent but more severe precipitation events in the Great Plains, altering the hydrologic regimes of streams. It is important to quantify species roles in these dynamic systems, because changes in stream communities are likely to accompany predicted changes in hydrology. The effects of species on ecosystem processes also are limited by the frequency of disturbance, because prairie streams are harsh, nonequilibrium systems characterized by a wide range of disturbances. In particular, frequent floods that reset the ecosystem to an early successional state can override the influence of consumer populations because the availability of resources is too unpredictable to maintain stable populations of those species or because species are absent following the flood. As flood frequency decreases, potential consumer effects may intensify. Using a combination of field and experimental stream mesocosm experiments, I (1) characterized the ecosystem effects of southern redbelly dace (Phoxinus erythrogaster), a grazing minnow, (2) tested the interactive effects of flood frequency and the presence of water column (red shiner; Cyprinella lutrensis) or grazing minnows (Phoxinus) on ecosystem processes, and (3) tested the effects of species loss from the grazer functional feeding group on stream ecosystem structure and function. I found that dace affected some aspects of ecosystem structure but not function, which suggested that grazer effects in prairie streams may not be consistent across taxa. In the context of flood frequency, both the water column omnivore and dace affected recovery of prairie stream primary producers following flooding disturbance by stimulating production, presumably through nutrient remineralization. However, some of these effects were transient or dependent on flood frequency, and my results indicate that consumer effects depend not only on environmental venue but also on the balance between consumptive losses and nutrient stimulation. In a comparison of the effects of removing different taxa from a grazer assemblage, the loss of crayfish, snails, or dace from a grazer assemblage did not differentially affect ecosystem processes, suggesting overlap in the ecosystem roles of these species in the context of this experiment.

Master of Science / Department of Civil Engineering / David R. Steward / Konza Prairie is one of the few areas in the United States were natural landscape of the area is still intact. Human action on changing the landscapes in this area is limited and much of the land remains as native grassland. In spite of its natural existence, this area is not completely isolated from the rest of the world. Changes that are taking place in climate will eventually have the same effect to this region as well as other human populated areas. Increase in carbon concentration in the air has resulted to increase in temperature, this increase in temperature increases the evaporation from the sea, oceans and the ice capes. As the atmospheric water vapor changes the precipitation pattern also change. Changes in precipitation due to climate change will result to change in hydrology and hydraulics of the streams and groundwater flow regime. Precipitation provides surface runoff and groundwater infiltration, which recharge the cracked limestone aquifer present in the Konza area. The infiltration water moves trough the cracked rocks and eventually reach the creeks such as Kings Creek and flow to the Kansas River. Increase in precipitation will result to increase in surface runoffs and more groundwater recharge. Decrease in precipitation will result to decrease in both surface and groundwater. To examine changes in groundwater elevation as recharge change in Konza, a groundwater model was developed based on erosion impact calculator (EPIC) ecological model and SLIT groundwater model. EPIC model estimates the deep percolation (recharge) as 12% and total runoff to about 24% of the annual average precipitation. The annual average recharge values from EPIC were used in SPLIT to simulate results for the groundwater elevation at Konza prairie. Field wells elevation were use to calibrate the SPLIT results. By estimating the hydraulic permeability value to 0.546m/d the field well measurements and SPLIT simulated groundwater elevation results provide a good match. After calibration max and min recharge together with a 5-years moving average were used to examine the changes in groundwater elevation as recharge changes. Future study intends to use the calibrated Konza groundwater model and the forecasted climate data to simulate result for groundwater elevation as climate changes.

Master of Science / Department of Biological & Agricultural Engineering / Stacy L. Hutchinson / Urban stormwater is one of the leading causes of water quality impairment and stream channel degradation in the United States. In an effort to address the negative effects of stormwater runoff on receiving aquatic systems, Best Management Practices for stormwater, including ecologically-designed stormwater systems, are becoming more common across the urban landscape. Throughout eastern Kansas and the rest of the Midwestern United States, prairie grasses are beginning to receive attention for their potential to enhance infiltration within these systems. However, the function of vegetated stormwater systems and the influence of factors such as vegetation age on infiltration and system performance are not well understood because monitoring data for these systems is limited. When performance data is collected, it often pertains only to the hydraulic and water quality aspects of the system but neglects any assessment of the integrity of the ecosystem functions on which the system's performance is dependent. The objective of this study was to address the need for an assessment tool that considers the ecological integrity, or health, of ecologically-designed stormwater systems, as well as to fill the gap in the literature regarding the function of ecologically-designed stormwater systems in the tallgrass prairie region. Since many of the eco-based stormwater practices in the region rely upon the establishment of native prairie grasses to enhance infiltration on the site, the specific focus of this study was to gain a better understanding of infiltration processes in ecologically-designed systems and the extent of our ability to regain these processes through prairie restoration in previously disturbed urban sites. To address these objectives, two stormwater systems at different stages of vegetative maturity were examined. In general, ecosystem health scores were higher for the more mature system and could be used to guide future management decisions at both sites. Results from the hydraulic analysis indicate the function of the system may improve over the course of the growing season, but statistical relationships between system age and infiltration rate could not be established.

This dissertation examines the multifaceted and pervasive impact of globalisation on the Canadian public policy environment through a detailed analysis of the monopoly marketing of prairie wheat. The study argues that forces associated with globalisation, working through regionally differentiated configurations of farmer opinion and interest groups amidst varying partisan settings, are key to understanding the changing nature of policy-making processes, structures, and outcomes in the wheat marketing arena. The forces associated with globalisation include the increased presence of transnational corporations, the expansion of international trade regimes, increased interaction and cooperation between Canadian provincial governments and US state governments, the international harmonisation of regulations, advances in transportation technology, and heightened levels of education, knowledge, and information. In attempting to understand how globalisation influences the wheat policy arena, the examination uses a comparative analysis focusing on Alberta, Saskatchewan, and Manitoba. The inter-governmental harmony that had prevailed since the 1940s on the matter of Canadian Wheat Board's (CWB's) wheat monopoly was replaced by conflict by the 1990s as the forces of globalisation washed across the Canadian prairies. The dissertation shows that where the absence of these forces once reinforced the CWB's wheat monopoly, the presence of these forces now poses a formidable challenge to its continuation. Farmer opinion data indicates that a trend away from monopoly selling toward open marketing is present throughout the prairies. Like the presence of the forces of globalisation, anti-monopoly opinion is particularly strong in Alberta. The dissertation will also show how the conflict over monopoly wheat marketing was projected into the policy arena through differentiated sets of interest group configurations and partisan environments. In doing so, the examination points out that institutions, while often providing resistance to change, can also serve as conduits facilitating change. The analysis shows that the public policy network involved with the marketing of prairie wheat, as well as actors within this network, have become increasingly internationalised. The examination indicates that domestic governmental regulation and control have been severely undermined in the wheat marketing arena as north-south ties increasingly undermine and replace the east-west unity previously forged by the National Policy. / Arts, Faculty of / Political Science, Department of / Graduate

The study of the economic development of the Gulf Coastal Prairie has been divided into the following seven chapters: (1) Physical Aspects, (2) Grazing, (3) Development of Farming, (4) Development of Transportation, (5) Development of Mineral Resources, (6) Development of Industry and (7) A Look to the Future.

The purposes of this study may be stated as follows: 1. To analyze the instructional procedures utilized by the coaching staff in the development of the T-wing football formation at the Grand Prairie High School, Grand Prairie, Texas. 2. To gain a better understanding of the functions of the T-wing football formation as it is taught at the Grand Prairie High School. 3. To make recommendations and to propose further developments for the instructional procedures used in coaching the T-wing football formation at the Grand Prairie High School.

A l’heure où l’on cherche à optimiser les services éco-systémiques fournis par les prairies, une meilleure compréhension du fonctionnement des systèmes racinaires apparait comme nécessaire. Nous avons donc décidé de caractériser les stratégies d’espèces issues des familles des Fabaceae et Poaceae prairiales par la mesure de traits fonctionnels racinaires. Le principal résultat de ce travail est la mise en évidence de plusieurs axes majeurs de différentiation des stratégies racinaires et de leurs relations avec les exigences écologiques des espèces. Le plus important est le compromis entre stratégies de capture et de conservation des ressources. Les espèces à stratégie de capture sont mieux adaptées aux milieux peu stressants notamment pour l’eau, mais sont peu impactées par le manque de phosphore, ce sont aussi des compétitrices efficaces. Bien que les plantes à stratégie de conservation soient mieux à même de se développer dans des milieux continentaux, elles sont plus impactées que les autres par la présence de compétiteurs et le manque de phosphore. Le type de relations existant entre les stratégies aériennes et racinaires apparait aussi comme un marqueur de l’adaptation des plantes aux stress. L’étude du système racinaire est donc un moyen efficace de prédire le comportement des espèces de plantes prairiales face à des contraintes abiotiques et biotiques. Cela ouvre des perspectives particulièrement intéressantes notamment pour la construction de mélanges d’espèces mieux adaptées à leurs environnements. / In order to optimise grassland ecosystem services we need to improve our understanding of root system functioning. As a result, we decided to characterise strategies of species coming from grassland’ Fabaceae and Poaceae families, by root functional traits measurement. The main result of this work is the establishment of several axes of root strategies differentiation. The main axis is the trade-off between resources capture and conservation strategies. Species with capture strategies appear to be adapted to non-water stressful habitat and are barely impacted by phosphorus shortage; they also happen to be strong competitors. On the opposite, species with conservation strategies are adapted to water stressful continental climates, but are strongly impacted by phosphorus shortage and happen to be weak competitors. The kind of relation between above-ground and below-ground strategies also appears to be a marker of the plants adaptation to stress. We showed that the root system study is a good way to predict grassland species comportment to face abiotic and biotic constraints. The present work widens interesting perspectives for the sowing of mixed grassland species better adapted to their environments.

North American prairie headwater streams are highly threatened and relatively poorly studied. Most studies on prairie streams have occurred at the Konza Prairie Biological Station, a tallgrass prairie Long Term Ecological Research site in the Flint Hills ecoregion near Manhattan, KS. According to the Stream Biome Gradient Concept, several ecosystem factors vary along a gradient from more allochthonous forested streams to more autochthonous desert streams, with grassland streams often intermediate in several key ecological factors including litter inputs, primary production, and invertebrate abundance and biomass. However, few studies have examined the degree of variation that exists within prairie headwater streams, and whether this variation occurs along a longitudinal gradient as well, with more mesic tallgrass prairie streams differing from more xeric shortgrass prairie streams, and mixed-grass sites intermediate between the two. I examined thirteen prairie headwater stream sites in the central United States from 2014 to 2017. My objective was to determine whether basal resource composition – including standing stocks of coarse particulate organic matter (CPOM), fine particulate organic matter (FPOM), and very fine particulate organic matter (VFPOM), sestonic and benthic chlorophyll-a levels, and sources of CPOM – differed significantly among streams in tallgrass, mixed-grass, and shortgrass prairie regions. In addition, I examined whether invertebrate communities differed among tallgrass, mixed-grass, and shortgrass prairie regions, and whether this was reflected in the functional feeding group composition, habit composition, voltinism, and dispersal ability of invertebrate communities. There were no significant differences in total CPOM, FPOM, and VFPOM standing stocks among regions. However, CPOM composition did differ with region, with tallgrass sites having higher standing stocks of leaf litter, but lower standing stocks of grass litter and macrophyte litter than the other regions. Benthic chlorophyll-a did not differ significantly among regions, but there were lower sestonic chlorophyll-a levels in tallgrass sites. Given higher light availability and nutrient levels in shortgrass and mixed-grass streams, lack of stable substrata may be limiting benthic algae in these regions. Invertebrate abundance and biomass were highest in mixed-grass sites and lowest in tallgrass sites, with shortgrass sites intermediate. Mixed-grass sites also had significantly higher Shannon diversity and taxa richness than tallgrass sites. A NMDS revealed that sites differed in overall community structure. Functional feeding group composition did not differ significantly across regions, with collector-gatherers, followed by predators, dominating in all sites. High Predator-Prey Index (predator biomass: other invertebrate biomass) values in each region indicates strong top-down pressure and high turnover rates of prey taxa. While there was a weak correlation between leaf litter AFDM and invertebrate community structure, the correlation between latitude and longitude and invertebrate community structure was much higher, indicating that basal resources may not be the main drivers in these systems. Invertebrate habit composition did not differ with region; all regions were dominated by taxa preferring fine substrata (burrowers and sprawlers). All regions showed selection against semivoltine invertebrates and were dominated by high dispersing insect taxa, though the proportion of the insect community that consisted of high dispersers did not differ significantly with region. My results suggest that generalizing about prairie streams based on studies from one or a handful of sites may not be prudent, at least for some aspects. The higher proportion of autochthonous inputs in shortgrass and mixed-grass regions may drive increased invertebrate abundance, biomass, richness, and diversity, but the relative hydrologic stability of the mixed-grass sites might also explain these results or have an interactive or additive relationship with primary production. Overall, the link between basal resources and communities across prairie types was somewhat weak, and all regions were dominated by collector-gatherers with rapid life-cycles and high dispersal abilities, indicating that disturbance may be a more important community filter than basal resource composition. Streams in all three regions have highly variable hydrology, and this may be an overriding factor that results in similarity in communities.

Nest success of dabbling ducks in the Prairie Pothole region of North America has been declining for the past 40 years in parallel with declines in duck populations. Low nest success seems to result from the combination of an extremely fragmented breeding ground in a human-dominated landscape with an abundant and expanding ii community of generalist nest predators. Studies that examined variables associated with nest vulnerability to predation have produced contradictory results, likely because of simplistic approaches, lack of spatio-temporal replication, use of artificial nests , and the effect of confounding variables. I attempted to clarify the equivocal findings of previous studies by using multiple regression to simultaneously examine the effect of several variables purportedly related to nest predation risk. I collected data on >1,800 dabbling duck nests and associated variables for 16 habitat patches (14 managed for duck production) during two nesting seasons in North Dakota. At the habitat patch level, early and late in each breeding season, I studied the relationship of nest success and upland area, nest density, predator abundance and richness, abundance of alternative prey for predators, and visual and physical obstruction provided by the vegetation . At the spatial scale of the nest and its neighborhood, I examined the likelihood of nest predation in association to nest initiation date, year, distance from nest to a wetland and to an edge, vegetation type at the nest, visual obstruction and heterogeneity of the vegetation around the nest, duck nest species , predator abundance, and presence/absence of 5 carnivorous predators at the nest habitat patch. Nest success was generally low and highly variable in time, and among and within habitat patches. I found no relationship between nest success and any of the variables measured at the patch scale. At the nest level, only initiation date, distance to water, visual obstruction, predator abundance, and duck species had an effect. High variability in the data and the lack of patterns in the relationship of nest predation and the predictor variables precluded me from building a predictive model that explains nest success. Nest success could not be predicted, predation was incidental and risk was high, and there were no safe nest sites for hens to choose in a landscape swamped by nest predators . Nests were located randomly; therefore, there were no clues predators could use to enhance their success in finding nests.

Understanding the relative importance of density-dependent and density-independent factors in driving population dynamics is one of the oldest challenges in ecology, and may play a critical role in predicting the effects of climate change on populations. We used long-term observational data to describe patterns in plant population regulation for 57 forb and grass species from three different ecosystems (arid desert grassland, semiarid sagebrush steppe, and subhumid mixed-grass prairie). Using a hierarchical partitioning approach, we (i) quantified the relative influence of conspecific density, heterospecific composition, and climate on temporal variation in population growth rates, and (ii) asked how the relative importance of these drivers depends on site aridity, species growth form and life expectancy, and abundance and spatial patterns. The data from one of the sites in this analysis are presented in one of the chapters of this thesis. We found that density-dependence had the strongest effect on species. Climate often had a significant effect, but its strength depended on growth form. Community composition rarely explained significant variation in growth rates. The relative importance of density, composition, and climate did not vary among sites, but was related to species' life histories: compared to forbs, grasses were more sensitive to climate drivers. Abundance and spatial clustering were negatively correlated with the importance of density dependence, suggesting that local rarity is a consequence of self-limitation. Our results show that interspecific interactions play a weaker role than intraspecific interactions and climate variability in regulating plant populations. Forecasting the impacts of climate change on populations may require understanding how changes in climate variables will affect the strength of density-dependence, especially for rare species.