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Understanding consistent individual variation in animal behavior is crucial for unraveling its ecological and evolutionary significance. Historically overlooked, such variation has profound implications for individual fitness, population dynamics, and species interactions. Genetic differences among individuals can significantly modulate behavior, yet studying this in natural environments remains challenging. Bio-logging technology offers a promising avenue for remotely quantifying animal behavior in the wild with realtime acquisition of abundant and precise data. Leveraging a genetic variant (Shank3 mutation) in prairie voles (Microtus ochrogaster), known for their social monogamy, we developed a bio-logging system to investigate individual behavior variation in naturalistic environments. Our study aimed to evaluate the system's effectiveness and explore the impact of the Shank3 gene on vole behavior. We found reduced sociality in Shank3 mutant female voles, reflected in increased interaction distances and possibly decreased huddling. Additionally, no differences were found in trappability, home range sizes, body weight, and survival days between Shank3 mutant and wild-type voles. Our results partially supported the laboratory findings of social deficits in Shank3 mutant female voles, but the underlying mechanisms may differ in natural settings. Overall, our study demonstrates the potential of bio-logging technology for studying animal behavior in complex ecological contexts and highlights the need for further research to understand the interplay of genetic and environmental factors shaping individual behavior.

Rapid climate change, alongside substantial habitat fragmentation, presents new challenges for biodiversity conservation in the tallgrass prairie. Therefore, capacity for adaptation in situ will be necessary for long-term population persistence. Populations with larger genetic variation likely have greater capacity for adaptation, but limited population sizes and restricted gene flow decrease this potential. Assisted gene flow (AGF) aims to increase adaptive capacity by introducing genetic material from populations that have undergone selection in warmer or drier environments. However, the addition of genetic diversity from geographically and genetically distant populations may disrupt local adaptation and ultimately decrease population performance. Here, I study how hybridization between populations over a geo-climatic gradient impacts their evolutionary capacity in response to warming temperatures. I used Chamaecrista fasciculata, a buzz-pollinated prairie annual to investigate the immediate and longer-term consequences of assisted gene flow in the Minnesota tallgrass prairie. In Chapter 1, I found that local gene flow increased population fitness compared to long distance or no gene flow scenarios in both ambient and warmed conditions and that the offspring of long-distance hybridization were limited by their capacity to germinate in Minnesota. In Chapter 2, I assessed how hybridization along this geo-climatic gradient impacted the capacity for ongoing adaptation and its dependence on environmental conditions. I found that the VA(W) of hybrids was more clearly expressed in warming conditions compared to the focal populations, thus providing evidence of capacity for adaptation in hybrid populations exposed to warmer temperatures. In Chapter 3, I evaluated the impact of hybridization on floral trait plasticity. Although I detected plasticity in almost all floral traits and found no significant difference in trait values between populations, the effect of those traits on population fitness differed significantly between populations. Together these chapters provide an empirical examination of the theoretical expectations of gene flow on a complex landscape and provide substantial evidence of the importance of maintaining genetically variable populations in a changing climate.

The shallow groundwater of the Sandhill Crane Wet Prairie in the Oak Openings Region of Northwest Ohio was modeled using the MODFLOW-NWT upstream weighting package (UPW) within the Aquaveo Groundwater Modeling System (GMS). The objective of this study was to characterize and better understand the hydrological response of a recently restored wet prairie in the Oak Openings at a high temporal resolution. Having a better understanding of the main processes driving the hydroperiods of wet prairies would help in determining the capacity of restored wet prairies for improving water quality and their response to climate change. Hourly water table elevations collected for a 10-month period: December 2019 - September 2020 were used to calibrate the model. The model also required hourly precipitation from Toledo Express Airport weather station, and estimation of evapotranspiration values.A 1-m DEM representing the top surface, hydrologic conditions, recharge rates, well locations and transient head boundaries was created using GMS. The conceptual model of the subsurface was developed using a combination of an electrical resistivity survey of a section of the wet prairie and interpolation of well log data from the Ohio Department of Natural Resources (ODNR) database. The model was calibrated using Parameter Estimation (PEST) with Singular Value Decomposition Assist (SVD-Assist) to best estimate the water table elevation collected in five monitoring wells installed in the study site. The simulated results tend to follow the overall trend of the observed water as determined by a statistical summary of the observed and simulated values for the calibration period. However, the model was not able to successfully simulate all the variability seen in the observed data set. MODFLOW was able to simulate the long-term trend of the data, but not its hourly peaks and valleys. Potential reasons for this limitation could be because of geological or hydrogeological characterization. It is not known if this lack of high-temporal variability simulation is a MODFLOW limitation or a parameterization issue.

Precise estimates of irrigation yield effects are essential for farmers when making irrigation investment decisions. The project goal is to improve our knowledge of irrigation yield effects in the soils of the Alabama Blackland Prairie region. The study objectives encompass estimating the irrigation yield effects of corn (Zea mays) and soybeans (Glycine max L.) based on terrain, soil, and climate parameters and determining the variables with the highest effect on crop yield. We evaluated two statistical analyses: Integrated Nested Laplace Approximation (INLA) and machine learning. The first analysis, assess the individual effect of irrigation, soil, and terrain properties on crop yield, and the second analysis evaluated four machine learning algorithms, including Sup port Vector Machine, Elastic Net Regression, Stepwise Regression, and Random Forest, under the following aspects: 1) identification of variables influencing yield predictions, 2) yield predictions based on adjacent fields, 3) yield predictions from irrigated fields, 4) yield prediction for a specific year utilizing data from other years within the same field, and 5) yield prediction of one field for a specific year using other fields with crop production in the same years. On an area of 3,400 ha with 22 pivot-irrigated and rainfed fields in the Alabama Blackland Prairie region, the research utilized 183 yield datasets collected from shrink and swell soils from 2012 to 2021. Spa tial derivatives derived from elevation information from the National Elevation Database, soil data from the POLARIS database, and drought indices calculated using precipitation, evapotranspira tion, and temperature data from the Parameter elevation Regressions on Independent Slopes Model (PRISM) Climate Group were integrated into the analysis. Results from INLA showed that terrain variables had a greater effect in corn than in soybeans yield. Although, these variables had the greatest effect, the yield increase or decrease was minimum in both crops. Results from machine learning showed that the accuracy of corn and soybean yield predictions is lower when relying only on one year of training data, where terrain attributes exhibited more significant influence compared to soil and climate properties. Conversely, incorporating data from multiple fields spanning several years and diverse crop yields into the training dataset led to greater accuracy of predictions, where the impact of climate properties is more notorious.

Despite making up less than two percent of the overall landscape in the arid and semi-arid western US, riparian areas are a crucial resource for agriculture, livestock, and wildlife. However, many have impaired function and reduced riparian cover. Low-Cost, Low-Tech Tools (LCLTT) are a subset of Process-Based Restoration (PBR) used for riparian restoration that were chosen for their cost-effectiveness and minimal technical requirements. LCLTT has been tested in mountainous areas of the western US but only recently implemented in the Northern Great Plains (NGP). Given their novelty as an approach toward restoration for the region, professional restoration and landowner communities are skeptical about LCLTT. The objective of this research was to address these concerns by determining the short-term impacts of LCLTT on vegetation communities and soil moisture (SM) in riparian areas located in livestock production systems. Forage production, SM, and the proportions of vegetation functional groups and ground cover were compared between stream reaches treated with LCLTT and untreated control reaches. The findings of this research show that in both the riparian corridor and historic floodplain, the LCLTT treatment reduced bare ground (-16% and -13%, P=0.04 and P=0.003, respectively) and increased upland vegetation (21% and 31%, P=0.002 and P < 0.0001, respectively), with increased surface water in the riparian corridor (13%, P=0.005) and increased graminoid vegetation (18%, P=0.0007) in the historic floodplain. Throughout the study, the upper 15cm of the soil profile had more moisture (0.08 m3/m3, P=0.04) in treatment reaches with an extended release of moisture during the summer. A seasonal analysis of SM showed no significant differences between treatment and control reaches during spring, but higher water content was observed in treatment reaches in the 0-15 cm range in summer (0.12 m3/m3, P=0.001), and both the 0-15 and 15-30 cm ranges in fall (both 0.13 m3/m3, P=0.0002). No changes to forage production were observed. Research regarding PBR from other locations showed similar changes to stream processes and plant communities in the early stages of restoration. While this research demonstrated short-term impacts in the initial year post-restoration, previous, longer-term research in other regions has observed that changes from PBR increase and compound with time. The results of this and similar research indicate that LCLTT could be a timeand cost-effective tool for landowners and managers to restore prairie streams and riparian areas in a livestock production setting in the NGP.

Woody plant encroachment is a global threat and has been transitioning grasslands to woody dominance at a biome scale. This threat is present in the Great Plains grassland biome which is currently experiencing grassland biome collapse as the alternative woody biome advances northwest. Nebraska, which contains the most intact temperate grassland in the world, is currently at the front lines of this large-scale transition making this state’s management decisions vital for the remaining grasslands and the species which rely on these ecosystems. In this study, we assess the vulnerability of Greater Prairie Chicken and Tier 1 at-risk species in Nebraska caused by the threat of grassland transition to woody dominance. Chapter one focuses on the threat of the advancing woody biome to Greater Prairie Chicken in Nebraska, utilizing two measurements to quantify risk. Chapter two utilizes participatory Tier 1 at-risk species assessments to assess statewide and regional vulnerability to Tier 1 species listed in Nebraska’s Natural Legacy project caused by the threat of grassland lost to woody dominance. Overall, the findings show that Greater Prairie Chicken, and key at-risk species found in Nebraska have become increasingly vulnerable to this threat. These results highlight the need for adaptive management strategies to mitigate the risk of woody encroachment and subsequent grassland transition to woody dominance. Advisor: Dirac Twidwell

Common Prairie is a full-length poetry collection. This work investigates the mythologies of place and considers where climate change and gender politics talk to each other within landscape—both physically and socio-historically. In these poems, I take an interdisciplinary approach to reimagined narratives of land, the past, and the self. I strive to fold together poetry and earth sciences—from soil chemistry to weather patterns to the extraction of natural resources. Similarly, I look to incorporate female voices from primary sources, folklore, and my own family experience into the study of sexuality, reproduction, and religion. At its core, this collection questions what it means to call a place home.

A green roof provides different benefits in an urban environment, like habitat, stormwater management, reduced energy usage, aesthetic values, and carbon storage. To understand the carbon storage capacity of green roofs, it is important to understand the amount of CO2 released (efflux) and taken up by the green roof. So, I measured and compared the above and belowground biomass, soil CO2 efflux (respiration), and associated soil parameters between the green roof and the prairie site to understand how environmental variables like soil temperature and moisture on the green roof influence CO2 efflux. The green roof substrate was significantly warmer than the prairie soil, and CO2 efflux from the green roof was less sensitive to temperature (i.e., had lower Q10) than the prairie site. I hypothesize that the porosity of the green roof substrate, which accounts for its lower water-holding capacity and volumetric moisture content, lowered the potential evapotranspiration and caused higher temperature and greater variation in temperature on the green roof. The green roof also had comparatively higher variation in substrate temperature, consistent with greater variation in CO2 efflux. The differences in the plant activity led to the major differences in the CO2 efflux between the green roof and the prairie site. Higher above and belowground (root biomass) on the prairie site led to higher total CO2 efflux on the prairie site as higher aboveground biomass can lead to increased photosynthates for the roots and higher root exudates along with the higher litter input, all of which can increase autotrophic and heterotrophic respiration. However, after accounting for the differences in root biomass on soil CO2 efflux (i.e., dividing efflux by root biomass), the green roof had higher efflux than the prairie sites, indicating a higher contribution of heterotrophic sources to CO2 efflux at the green roof. Since the green roof at Schoonover Center is unique due to its location, climate, aspect, and species composition, the result might not be similar to other green roofs. However, a long-term study of the trends of soil organic matter concentration over the years, along with measurements of parameters like CO2 efflux and net primary productivity, can help determine whether the green roof at Schoonover Center can store carbon.

Largely known for her choral compositions, American composer Gwyneth Walker (b. 1947) has composed hundreds of songs for solo voice. Walker’s songs demonstrate her unique compositional style which blends many characteristics of American music, including strong rhythms, open sonorities, and influences of rock, jazz, blues, and American folk music. With each work, Walker’s goal is not only to communicate to the audience, but for the music and poetry to deliver a specific musical imagery. Walker believes that the message of a song is not solely the poetry, but that the central images of the poem are the message. Walker believes that it is only when these images are combined with music that you have words. The result of this unique compositional style is over ninety songs for solo voice that are accessible to many performers. This document is organized into four chapters: chapter one includes an introduction to the study, review of literature, and a brief biography of Gwyneth Walker, Carl Sandburg, and Willa Cather. The second chapter includes a formal overview and discussion of the individual Prairie Songs. Chapter three is a discussion of Walker’s compositional style, the compositional process of Prairie Songs, and Walker’s relevancy as a twenty-first-century American woman composer. The fourth chapter is a summary of findings and conclusions. Finally, the document includes five appendices that contains a list of the poems from Prairie Songs, a list of musical figures, transcripts of interviews, emails between the composer and author, a catalogue of Walker’s published and recorded songs, and a bibliography. Advisor: Jamie Reimer Seaman

Adult behaviors are the result of interactions between an individual’s genes and their developmental environment. Although past research has demonstrated the importance of early-life experiences in later behavior, most work focuses on the impact of a single experience. However, early life is a slew of experiences that can interact with each other, and adult phenotypes may be the result of a suite of interrelated developmental experiences. Here, I explore the potential variation and impact of three interconnected developmental experiences in the prairie vole: parental care, alloparental experience, and exposure to the nonapeptides oxytocin (OT) and arginine vasopressin (AVP) (introduced in Chapter 1). I then characterize the variation present in prairie vole parental care and show that pups prefer to interact with their mothers over fathers, regardless of this variation (Chapter 2). This maternal preference disappears after weaning. Next, I explore the behavioral and neural components of alloparenting in subadult (post-weaning, pre-sexual maturity) prairie voles by exposing them to one of four stimuli: a same-age sibling, a related neonate, an unrelated neonate, or an inanimate object (Chapter 3). Subadult alloparents show no difference in the amount of care they give to related and unrelated neonates and no difference in OT or AVP activation in the paraventricular nucleus of the hypothalamus (PVN) or supraoptic nucleus of the hypothalamus (SON) across stimuli. This suggests that subadult alloparental experience is important practice for their future parenting. I then explore using the Morris water maze how chronic and acute intranasal administration of OT and AVP impact spatial memory in adulthood, a form of cognition underlying monogamous mating tactics (Chapter 4). Only chronic administration of AVP during post-weaning development influences spatial memory, specifically by improving it. Finally, I speculate on ways all three developmental experiences may impact each other and influence adult cognition (Chapter 5). I hypothesize that these early-life experiences can interact with each other to ultimately organize neural phenotype, thereby affecting the adult behavioral phenotype. Experiences during development can cause a cascade of potentially interconnected events that account for the range of adult behaviors linked to early-life variability.

Prairie has become one of the most endangered biomes in North America under changing climates engendered by anthropogenic activity. The patterns of diversity we observe of native prairie species in remnant prairie sites are the outcome of both historical and contemporary processes, and understanding these underlying processes will inform the responses of these populations to future environmental changes. The assembly of fungal endophyte communities within plants depends on the complex interactions of fungal taxa, their host plants, and the abiotic environment. Prairie plant communities provide a unique avenue to explore the interplay of biotic and abiotic factors affecting endophyte communities, since the historical distribution of prairies spans a broad range of temperature and precipitation, while the distances between small fragments of contemporary prairie communities may challenge the dispersal capabilities of these otherwise ubiquitous fungi. We sampled foliar fungal endophytes from two native prairie legumes, purple and white prairie clovers (Dalea purpurea and D. candida), in 17 remnant prairie sites across Minnesota in order to evaluate the relative contributions of abiotic factors, host species, and dispersal limitation to the diversity and structure of these communities. We found that similarity of communities was significantly associated with their location along a temperature and precipitation gradient, and we showed a distance-decay relationship that suggests dispersal limitations only over very large spatial scales. Although the effect of host species was small relative to these other factors, the two Dalea species maintained distinct communities within sites where they co-occur. Our results illustrate the capacity of many of these endophyte taxa to disperse over large distances and across heterogeneous biotic and abiotic environments and suggest that the interplay of biotic and abiotic factors maintains high diversity observed in endophyte communities. Our results showed that community composition of endophytic fungi in Dalea spp. varied along a precipitation and temperature gradient, among hosts, and in apparent response to the abundance of Alternaria spp., but left unexplained patterns of genetic variation among the many isolates assigned to Alternaria alternata. We used genotyping-by-sequencing (GBS) to assess population genetic structure of endophytic Alternaria among sampling sites and between host species, and compare levels of recombination and clonality and assess evidence for sexual or parasexual reproduction in these communities. We found cryptic diversity among sequenced samples, as only a subset aligned well to A. alternata reference genomes. Analysis of sequences closely related to reference A. alternata genomes, treated here as a single species, revealed a high level of clonality, and genotypic diversity shared across populations. However, we also detected evidence of recombination events consistent with sexual or parasexual reproduction, as well as two mating types, MAT1-1 and MAT1-2, which were present in roughly equal frequencies in all but one sampled population. Together, the results suggest recent asexual proliferation after rapid colonization of the sampled sites from an ancestral source population. Recombination likely occurred more frequently in the source population, and is now rare.

Prairie cordgrass (Spartina pectinata) (PCG) is a warm-season perennial grass that can be used as a biofuel feedstock and can be grown on marginal lands. Previous studies on intercropping of a perennial legume i.e., kura clover (Trifolium ambiguum) (KC) with PCG can improve soil biochemical properties, increase biomass production, mitigate greenhouse gas (GHG) emissions while reducing the chemical fertilizer requirement. However, there is a lack of evidence about the effects of PCG production on soil biochemical and physical properties during the cropping season and at deeper soil depths in reference to support plant growth, environmental implications and enhance the soil health of marginal lands. The overall objective of this study was to investigate the effects of PCG-KC intercropping on (1) soil biochemical properties at different sampling times during the season, and at different soil depths up to 60 cm, and (2) near-surface (0- 10 cm depth) hydro-physical properties. This field experiment was initiated in 2010 as a randomized complete block design with four replications of five treatments i.e., PCG intercropped with KC (PCG-KC), and PCG fertilized with different N fertilizer rates: 0 (PCG-0N), 75 (PCG-75N), 150 (PCG-150N), and 225 N kg ha-1 (PCG-225N). For seasonal biochemical properties assessment, surface soil samples were collected at 0-10 cm depth at three different times during the crop season: pre-emergence (PE), active growth (AG), and after harvest (PH) stages. To investigate the long-term effects on soil total carbon (TC) and total nitrogen (TN), deep soil cores were collected from 0-5, 5-15, 15-30, 30-45 and 45-60 cm depth after the crop harvest. The intact soil cores from 0-10 cm depth were collected at the AG stage to measure the soil physical properties. Overall, microbial biomass carbon (MBC) and nitrogen (MBN), and urease activity, were observed to be higher at the PE stage as compared to AG and PH stages. No treatment effect was observed for both MBC and MBN. Cold water-extractable C (CWC) showed a gradual increase from PE to AG to PH. Whereas, hot water extractable C (HWC), β-glucosidase activity, FDA, and glomalin, were highest at the AG stage and lowest at PE stage. The treatment effect was not significant for CWC, HWC and glomalin whereas, treatments had significant effect for all the enzymes, PCG-KC treatment had 45% higher mean β-glucosidase activity when compared to control (PCG-0), 56 and 42% higher mean urease compared to PCG-0 and PCG-75 N, and 13-19% higher FDA activity compared all other treatments. Total PLFA, bacterial, and fungal PLFA, CWN increased from PE to AG stage and showed similar or decreasing trend from AG to PH stages whereas HWN content decreased from AG to PH stage. Treatment effect was not significant for total PLFA and bacterial PLFA. There was a significant interaction between treatment and stage for CWN and HWN; PCG-KC showed higher mean values of CWN compared to PCG-0, PCG-75N and PCG-150N during the PE stage and was similar to all other N treatments except PCG-225N. PCG-KC had higher mean HWN when compared to control i.e., PCG-0 during AG stage and PCG-225N at PH stage. Nitrate concentration was higher at PE stage when compared to AG and PH stage which is contrary to the ammonium concentration that showed an increasing trend from PE to PH stage. Both the parameters had significant interaction between treatment and stage. The PCG-KC treatment had showed 34.3 and 24.4% lower nitrate concentration than PCG-150 and 225N during the AG stage and 24.3% lower than PCG-150N at PH stage. For ammonium PCG-KC treatment had a higher mean value than the control i.e., PCG-0 during PE stage and PCG-75N at PH stage. There was a gradual decrease in both TC and TN concentrations with soil depth. In the 0-5 cm layer, soil TC concentration was approximately 43% higher when compared to 45-60 cm soil depth. Similarly, TN concentration was approximately 83% higher in 0-5 cm soil layer when compared to deeper soil depth i.e., 45-60 cm. There was no treatment effect and its interaction with depth. The intercropping of KC with PCG had 0.024 cm3 cm-3 of macroporosity (MP), 50% higher Ksat, and 1% lower λ as compared to the other treatments. Moreover, PCGKC treatment had 1.42 g kg-1 of TN and 21.4 g kg-1 of TC in the surface layer which was comparable with PCG-75 treatment, however, were significantly higher as compared to the PCG-0. Overall, this study showed that the long-term maintenance of KC with PCG can provide soil health benefits through enhancing or maintaining the soil biochemical and hydro-physical properties. Therefore, long-term adoption of the perennial grass-legume system can enhance soil functional processes including, nutrient cycling, C sequestration, water storage, and availability, while maintaining biomass yields for biofuel production on marginal lands.

The planet’s arable soils are rapidly degrading, primarily through mismanagement, erosion, and pollution. In contrast, some of the most fertile soils in the world lie under grasslands, such as in the Central Plains region of the United States. These soils were developed over thousands of years through wind depositions and through the deep roots of native grasses and forbs, each year depositing the organic matter and carbon of old roots under the surface. The eastern edge of US grasslands is occupied by Tallgrass Prairie, 98% of which has been converted to row crops and human use. There remains, among these soils, small remnants which have remained uncultivated or plowed, and which are likely the best remaining examples of grassland soils from before modern agriculture. To improve and preserve the agricultural soils throughout the Midwest, it is essential to thoroughly understand the soil properties of these remnant soils. Currently the most widely recognized and comprehensive suite of soil tests available for analyzing chemical, physical, and biological aspects of soil is the Comprehensive Assessment of Soil Health offered by the Cornell Soil Health Laboratory (CSHL). Multiple government and research groups use this testing service for the quantification of soil health properties. The goals of this study are to use Cornell University’s Comprehensive Assessment of Soil Health tools to: 1) evaluate the soil health of remnant tallgrass prairies in Nebraska, by quantifying a suite of relevant physical, chemical, and biological soil properties collected at multiple remnant sites; 2) compare the data from these remnant grasslands with comparable data collected in nearby agricultural fields to determine the degree and type of soil degradation which may have occurred there; and 3) use the profile characteristics of the remnant soils as a benchmark for evaluating soil health of samples derived from a region-wide data base for agricultural soils of collected from former prairies throughout the Great Plains. In the Nebraska Tallgrass Prairie region, nine research sites were identified. Five remnant sites were paired with one of four nearby agricultures sites that had a similar soil type, slope, and elevation. At each site, five subsamples were collected at 0-15 cm and at 15-30 cm soil depths. The samples were analyzed for soil texture, available water capacity, organic matter percentage, soil protein, soil respiration, active carbon, pH, total carbon, total nitrogen macro and micronutrients. The data analyses were conducted using R Studio, and the results of the remnant sites and of the agricultural sites were compared: 1) with each other, and 2) with selected samples from the CSHL Prairie State Database (PSD). There were significant differences between the remnant soils and the agricultural soils at 0-15 cm. Differences were most pronounced in the biological soil properties, with remnant soils exhibiting higher values among soil health properties that measure soil functional capacity. This pattern was also evident in the physical soil properties, although the differences were not as pronounced. In the chemical analyses, higher nutrient concentrations were found in the remnant sites than in the agricultural sites, apart from phosphorous, which was significantly higher in the agricultural sites. Similar patterns were found in the samples from 15-30 cm depth, although less pronounced. Pearson’s Correlation revealed significant correlations among the biological indicators, particularly among carbon-related soil properties. In addition, a Principal Component Analysis identified associations among indicators strongly associated with microbial activity and organic matter quality. Comparison of the Nebraska samples with the Prairie Soils from the broader CSHL data base was especially insightful as soils from the remnant sites had higher soil health indicators for every property measured, except phosphorous, iron and zinc. In general, this study indicated serious degradation in the agricultural soils as compared with the remnants, with total nitrogen showing the highest difference, followed by various forms of carbon. The comparison of remnant prairie sites with agricultural sites in eastern Nebraska quantified what is apparently a breakdown of healthy soil functions in active agricultural land, as a result of long-term agricultural practices. The remnant soil health profiles presented here can therefore serve as a reference for guiding management and restoration of agricultural systems throughout the Tallgrass Prairie Region. This study also highlights the powerful approach of using the CSHL comprehensive soil analyses in combination with remnant grasslands as a diagnostic tool for other types of grasslands across the Great Plains and globally.

Ohio historically hosted a patchwork of tallgrass prairies, which provided habitat fornative species and prevented erosion. As these vulnerable habitats have declined in the last 200 years due to increased human land use, restorations of these ecosystems have increased, and it is important to evaluate their success. The Hemiptera (true bugs) are an abundant and varied order of insects including leafhoppers, aphids, cicadas, stink bugs, and more. They play important roles in grassland ecosystems, feeding on plant sap and providing prey to predators. Hemipteran abundance and composition can respond to grassland restorations, age of restoration, and size and isolation of habitat. I investigated the effects of these variables on the abundance and composition of Hemiptera within 13 Ohio prairies in order to answer 4 questions regarding prairie restoration: Do older constructed prairies resemble remnant prairies in hemipteran abundance, diversity, and composition more than they resemble newer constructed prairies? Does the size of a prairie fragment affect the abundance, diversity, and composition of Hemiptera? Does the distance of a prairie to an agricultural field affect the abundance, diversity, and composition of Hemiptera? Do any hemipteran morphospecies indicate particular prairie types? Insect samples were taken via sweep net from 13 prairies (6 remnant, 4 old constructed, 3 new constructed) in 4 southwestern Ohio counties in summer 2019, and were sorted to order. I then sorted hemipterans to family and morphospecies, and analyzed their abundance and composition.I found no significant difference in hemipteran abundance or number of families/morphospecies between remnant, old constructed, and new constructed prairies in summer 2019. However, in July 2019, remnant prairies had a significantly higher hemipteran diversity than old and new constructed prairies. In August 2019, NMDS ordination showed that hemipteran morphospecies composition in new constructed prairies diverged from remnant and old constructed prairies. These results suggest that while the hemipteran community is largely similar across remnant and constructed prairies in this system early in the summer, the communities begin to diverge as the growing season progresses. Additionally, in June 2019, two morphospecies (Miridae: Lygus lineolaris and Psyllidae: Craspedolepta sp.) had a significant negative relationship with age of constructed prairie, and another morphospecies, Membracidae: Micrutalis calva was an indicator of remnant prairies. Finally, in July 2019, the family Membracidae increased in abundance as distance to agriculture increased. The relationships seen within these hemipteran families suggest that constructed prairies may need more maintenance over time to better replicate the conditions of remnant prairies, and that close proximity to agriculture may be limiting the potential of all prairies in this region.

My thesis focuses on the conservation consequences of the hybridization of Lesser Prairie-Chickens in Kansas. Specifically, examining how past land management practices altering the species ranges impact the distinctiveness of Lesser Prairie-Chickens. Each chapter is an individual publication that addresses if the Greater and Lesser Prairie-Chicken are distinct when applying the morphological and biological species concepts. Chapter 2 compares the evolutionary history and morphological construct of Lesser Prairie-Chickens and other Galliformes using morphometric analysis. Chapter 3 uses low-resolution microsatellite data to reflect recent changes at the population level. This study aims to observe the Greater and Lesser Prairie-Chicken using the morphological and biological species concepts, two of the many species concepts, to determine the distinctiveness and rate of hybridization for these closely related species.

Abstract: Background: Given the complex etiology of type 2 diabetes (T2D), the Diabetes Canada Clinical Practice Guidelines recommend a multidisciplinary approach for its management, in which self-management education and support, nutrition therapy, physical activity and pharmaceutical therapy play major role. However, people with T2D face difficulties in following these guidelines especially in regards to nutrition therapy. Consequently, lifestyle intervention (LI) programs help guide participants through the overwhelming process of acquiring necessary knowledge and skills. The goal of the work presented in this thesis was to provide strategies that enhance participants’ successful adherence to the guidelines through the evaluation and optimization of the Pure Prairie Living Program (PPLP), a LI developed previously. Thus, the primary objective of this thesis was to evaluate the effectiveness of the PPLP in a primary care setting. Guided by results obtained from this randomized controlled trial (RCT), two additional objectives were examined: i) To analyze to what extent LI programs align with the cornerstones of T2D management and to compare their effect sizes when moving through the scale-up process (efficacy trials to effectiveness trials) ii) To understand the lived experience of people with T2D when managing their disease, in order to identify optimization strategies for the PPLP and other LI programs. Methods: The PPLP intervention was a 2-arm, parallel group, RCT. Participants were blinded to group assignment through concealment of allocation until assignment occurred. The program spanned 6 months from recruitment to the final participant visit. Baseline, 3- and 6-month assessments were carried out in the PPLP intervention group (n = 25) and wait-listed controls (CON, n = 24) to assess anthropometric, metabolic and demographic information. In the intervention arm participants attended and participated in 5 weekly nutrition education session (~ 90 min each). They received the PPLP resource pack that consisted of a copy of the nutrition education presentations each week and a copy of the PPLP workbook to guide them though the educational sessions and provide support, positive reinforcement of concepts and the opportunity for skill acquisition. Lastly, a copy of the Pure Prairie Eating Plan was provided to facilitate and guide participants towards healthy eating options. A detailed summary of intervention activity content, educational sessions and support materials can be found at www.pureprairie.ca. During the 3-month evaluation, two focus groups with the intervention group were carried out. After the 6-month evaluation, the waited listed control group started the education sessions. For the analysis of LI alignment with the guidelines, a systematic review methodology was adopted guided by PRISMA guidelines. Studies reporting on real-world LI that included at least two of the main pillars of T2D management in accordance with the Diabetes Canada Clinical Practice Guidelines, had gone through scale-up process (efficacy (research setting) to effectiveness (real-world setting)), and reported HbA1c were included. Multiple databases were searched and titles and abstracts, then full texts were reviewed based on the predetermined inclusion and exclusion criteria. For studies meeting the inclusion criteria, research setting pairs were retrieved. Risk of bias components were assessed using the Joanna Briggs Institute templates. To understand the lived experience of people with T2D an explorative qualitative study design was undertaken guided by COREQ checklist. Purposeful sampling was used to recruit 15 participants who had participated in LI programs and/or had past consultations with any health care provider (HCP) regarding their T2D. One-on-one, semi-structured, open-ended, in-depth interviews were conducted. An essentialist paradigm was adopted to report experiences, meaning and the reality of participants. An inductive approach was used to analyse the data. Results: The RCT intervention yielded no significant within-group changes in HbA1c at 3- month (-0.04 (-0.27 to 0.17)) and -0.15 (-0.38 to 0.08)) or 6-month (-0.09 (-0.41 to 0.22)) and (0.06 (-0.26 to 0.38)) follow up in either CON or PPLP groups, respectively. Dietary adherence scores improved in the PPLP group (p < 0.05) at 3 and 6 months but were not different in the between-group comparison. No changes in diabetes self-efficacy scores were detected. Participants described the program as clear and easy to understand. Knowledge acquired influenced their everyday decision-making but participants faced barriers that prevented them from fully applying what they learned. Healthcare professionals enjoyed delivering the program but described the “back-stage” workload as detrimental. The main results of the systematic review found that all the studies analyzed reported a decrease in HbA1c values in the intervention group and that a scale-up penalty was detected ranging from 22 to 35%. Furthermore, comprehensive LI that incorporated most of the cornerstones of T2D management reduced HbA1c in research settings and generally sustained those benefits in realworld setting, albeit with a scale-up penalty under some circumstances. Findings from the qualitative study reflect 5 important results. First, participants’ reality of living with and managing T2D can be overwhelming; effective T2D management address individuals’ context. Second, T2D management is influenced by and forms part of a complex, evolving system in which a person’s behaviour is influenced not only by their personal health background and history, but also by their external environment where work, family and HCP influence their behaviour towards more positive or negative outcomes. Third, participants cycled through good behaviour and bad behaviour with social factors, resources, the food environment and competing priorities influencing these cycles. Fourth, people with T2D indicated that all the cornerstones of T2D management should be integrated into LI including foot, eye and dental care. Several program characteristics including active learning and hands-on approach were desired for all of the knowledge being taught; furthermore, close follow up and intervention maintenance strategies should be incorporated. Lastly, HCP and researchers should understand who each individual participant is, because through this understanding they can provide appropriate, directed advice that will be effective for each individual context. Conclusion: While some positive effects of the PPLP intervention were observed, they were not comparable to those previously attained by our group in an academic setting or to what the guidelines recommend, which reflects the challenge of translating LI programs to real-world settings. However, the finding of a modest scale-up penalty does not negate that real-world application of LI programs can result in clinically relevant improvements in T2D outcomes, particularly if interventions support and promote the importance of each cornerstone of T2D management and work with patients to help them increase or maintain their focus or inclusion of each behaviour over the long term. Including input from participants’ context, experiences and needs, will provide more sustainable and realistic LI programs. People living with T2D request a more extensive and comprehensive treatment to address the multifaceted etiology of this chronic disease. Shifting of program content, delivery and long-term maintenance is required to address participants’ needs.

Marshbirds are difficult to survey due their secretive nature and association with dense wetland vegetation. Recently developed standardized survey protocols are used to monitor patterns of abundance, primarily at large spatial scales, but also can be used to assess marshbird response to management. We estimated abundances of 5 species of marshbirds (American bittern [Botaurus lentiginosus], least bittern [Ixobrychus exilis], pied-billed grebe [Podilymbus podiceps], sora [Porzana carolina], and Virginia rail [Rallus limicola]) in relation to vegetation management techniques of Prairie Pothole wetlands. In northwestern Minnesota, management in autumn 2105 included herbicide application to wide-spread cattail (Typha spp.) mats with the goal to break up dense vegetation patches and restore wetlands to hemi-marsh conditions. In a before-after, control-impact study design we conducted standardized call-broadcast surveys for marshbirds during breeding seasons 2015 – 2018. We observed that American bittern, pied-billed grebe, sora, and Virginia rail abundances initially decreased, and then increased at 2nd and 3rd seasons post-treatment at sites where herbicides had been applied. In west-central Minnesota, long-term vegetation management included varying frequencies of multiple control methods. Using a habitat-informed detection probability we transformed bird counts to densities to compare abundances of marshbirds across survey locations surrounded by variable amounts of suitable habitat. We compared abundances of marshbirds among categories of wetlands with management histories of low frequency of prescribed fire, high frequency of prescribed fire, and high frequency of prescribed fire and grazing. Fire and grazing as applied in the system we studied did not appear to influence Prairie Pothole Region wetland characteristics enough to result in changes in marshbird abundance, but abundance of marshbirds was related to characteristics of individual wetlands that did not appear to respond to fire and grazing. Pied-billed grebe abundance was positively associated with higher areas of open water, soras were more abundant in wetlands with high ratios of open water to emergent vegetation, and Virginia rails were more abundant in wetlands with scrub-shrub wetland cover types.

Ecological restoration is an important tool in the conservation of tallgrass prairies and native bees in intensively farmed regions. However, these same agricultural landscapes may alter the types of bees that can colonize and persist in prairie restorations due to fragmentation and biotic homogenization. My dissertation explores how bee community diversity, heterogeneity, and composition in prairie restorations change in response to an increasing gradient of agricultural land cover in Western Minnesota. In an effort to better understand if agricultural land cover impacts the ability of prairies restorations to conserve at-risk bee species, I utilize this gradient to compare native bee communities in prairie restorations to those in prairie remnants, and attempt to compare differences in rare and declining species. Bee communities in prairie restorations were surprisingly diverse and heterogeneous despite high levels of agricultural land cover. While there were differences in bee community composition between restored and remnant prairies, these differences were related to dramatically different floral communities. Overall, my results show that bee communities in prairie restorations are surprisingly resilient to high proportions of surrounding agricultural land, and suggest that highly agricultural landscapes should not deter restoration and conservation practitioners from restoring degraded land in these regions.

The Nebraska Game and Parks Commission (NGPC) has monitored greater prairie-chickens (Tympanuchus cupido pinnatus) and plains sharp-tailed grouse populations (Tympanuchus phasianellus jamesi), collectively known as prairie grouse, since the 1950s using spring breeding ground counts. My research modeled long-term, species-specific spatial and temporal trends of prairie grouse abundance and potential environmental drivers in the Sandhills of Nebraska using NGPC’s historical monitoring data. Prairie-chicken populations have increased since the 1950s while sharp-tailed grouse populations have remained stable or slightly declined. These population trends arise in the context of a dynamic landscape. I created indices representing raptor predation and hunting pressure, cropland, hay and CRP acreage, cattle stocking rate, drought and winter severity, landscape-level factors known to influence prairie grouse populations via mechanisms supported in the literature. I used a Ricker population process model in a Bayesian state-space framework to explore the relationship between species-specific breeding ground count data and environmental covariates with a one-year time lag. I incorporated indicator variable selection into the model to determine which covariates most strongly influence population trends. The most competitive greater prairie-chicken model included negative density dependence (β = -0.003, SD = 0.000, BCI = -0.004 - -0.003) and a positive effect of increased precipitation during the previous spring (β = 0.046, SD = 0.021, BCI = 0.005 - 0.089) on population growth rates. The sharp-tailed grouse model that received the most support included negative density dependence (β = -0.005, SD = 0.001, BCI = -0.007 - -0.003) and a negative effect of increasing cropland acres (β = -0.084, SD = 0,041, BCI = -0.168 - -0.005). The effect of grazing was also strongly supported for both species. Although prairie-chickens and sharp-tailed grouse have traditionally been managed as a single species because of their similar resource needs, my findings suggest that prairie grouse conservation measures may be more successful if they are tailored to individual species. My study provides a framework for wildlife managers to use existing count-based monitoring records and free, publicly available environmental data to explore population drivers in addition to abundance trends.

The prairie vole (Microtus ochrogaster) is a monogamous rodent currently classified into seven subspecies across central United States and south-central Canada. However, conflicting data from recent morphological and nuclear DNA analyses suggest further phylogeographic study is warranted. The primary objective of my study was to conduct the first phylogeographic analysis of prairie voles using mitochondrial DNA sequence data. I sequenced an approximately 505 base pair region of cytochrome b from 40 individuals across the species range that represented six of the seven current subspecies. A spatial genetic cluster analysis yielded three clusters. The largest cluster contained 73% of the individuals sequenced including representatives from the six subspecies. A haplotype network and phylogenetic reconstruction suggested further substructuring within the smaller clusters. Overall, my results, and a prior analysis of nuclear data, suggest panmixia with high gene flow throughout the species range. Interestingly, the genetic structure from the mitochondrial data does not match the structure from the nuclear data. This discordance is likely caused by incomplete lineage sorting due to recent range expansion. Furthermore, the mitochondrial genetic structure is not consistent with the currently accepted geographic ranges of the seven described subspecies and suggests that past subspecies classifications need to be reevaluated.

Critical social interactions between animals such as courtship and competition over resources are mediated by communication signals, which have evolved via natural or sexual selection. Signals may have evolved to transmit information about senders, to affect receiver responses, or both. Birds have long served as focal organisms in studies of signaling, as many avian signals have undergone extensive elaboration. The role of avian signals in breeding behavior is also well studied, as many signals evolved specifically for use in this context. Additionally, birds exhibit several types of mating systems and the reliability of signal information may vary between mating systems. Among birds, some grouse species are distinguished by a promiscuous mating system which is often centered on leks. Although these species exhibit the classic lek-mating system, several questions related to signals transmitted during breeding behavior remain scantly researched.The research in this dissertation focuses on signals employed in the breeding behavior of the lek-mating lesser prairie-chicken (Tympanuchus pallidicinctus), a North American grouse (sub-family Tetraonidae). Males display two sets of bright, conspicuous color ornaments used in visual signaling and sound production during breeding behavior. I tested the hypotheses that these ornaments are honest signals of age, condition (Chapter 2), and parasite loads (Chapter 3). Additionally, I considered the effects of ornament size and color properties on male mating success and the performance of male duets which are unique to the lesser prairie-chicken relative to other grouse. In Chapter 4, I tested the hypothesis that females rely on the interpretation of multiple male signals when choosing mates, and in Chapter 5 I explored three non-mutually exclusive hypotheses related to male duets: 1) duets serve as an endurance contest, 2) duets serve as a mechanism to de-escalate or prevent violent interactions between males, and 3) duets are intended as signals for females or have different functions when females are present or absent. By focusing on the honesty of signal information and the responses to signals by receivers of both sexes, this research addresses the key questions related to animal communication signals.The main findings of this research are that color ornaments in male lesser prairie-chickens do not serve as signals of age or body condition, but that they respond to manipulation of endoparasite loads, suggesting that they serve as reliable signals of parasite abundance. Ornament color properties correlate with mating success, which is also predicted by age, behavior rates, morphological trait size, and characteristics of territories held on breeding grounds. Male duets do not appear to function as endurance contests, but they may help to reduce physical conflict. Duet structure differs when females are absent versus present and duets may serve different functions under these two conditions. Overall, these results indicate that color, vocalizations, and locomotor signals in the lesser prairie-chicken reliably transmit information and that this information informs mate choice, suggesting that signal interpretation allows females to procure benefits for themselves or their offspring.

Tallgrass prairies are one of the most endangered ecosystems in North America. Habitat loss and degradation of remaining prairies threaten both the biodiversity and functioning of these ecosystems. At the landscape scale, loss and fragmentation of existing prairie may limit regional pools of species and abundance of individuals, hampering movement of plants and animals between suitable habitats. At the local scale, degradation of prairies has been exacerbated by loss of native grazers and suppression of fire, the major ecological forces that historically shaped prairie species and communities. While the impacts of these factors on biodiversity in prairies is well-established, little is known about the role of these factors on plant-pollinator interactions, an important ecological process for many prairie forbs. As restoration of prairie habitats is one of the chief means of protecting prairie habitats and biodiversity, evaluating the roles of these factors in mediating ecological processes such as pollination will be critical to their reconstruction. Within this thesis, I explore how two important aspects of habitat restoration management, landscape context and prescribed burning, influence pollination in two common, widespread prairie forbs reliant on insects, namely bees, for pollination. The findings of these studies serve as initial assessments of two under-explored topics with relevance to tallgrass prairie conservation: how placement of a restoration effects recruitment of pollinators and the pollination they provision a habitat, and how animal-mediated pollination influences prescribed burning’s effects on plant reproduction.

Tallgrass prairies of North America are under threat from a number ofanthropogenic disturbances including the introduction and expansion of nonnative plant species. One potential mechanism for successful invasion by nonnative plants is alterations of native soil microbial communities, including symbiotic arbuscular mycorrhizal (AM) fungi. Restoration projects typically focus on aboveground processes with less focus on altered belowground aspects. However, to successfully restore prairiesfollowing invasion by non-native plants, a deeper understanding of belowground alterations facilitating invasive dominance and hindering native reestablishment is needed. A restoration project focused on repairing belowground processes following invasion by Bothriochloa bladhii was established at the Konza Prairie Biological Station near Manhattan, KS. This study evaluated the influence of native AM fungal communities on establishment and survival of reintroduced native plant species following eradication of the invasive. Seedlings received one of three soil microbial inoculants (whole prairie soil, selected AM fungi, or sterile soil), prior to introduction into the study site. Evaluations of species diversity, survival, and return of the invasive plant were conducted for five years following transplant. No significant differences in diversity were observed, which likely stemmed from a high rate of return of the invasive. Overall, whole soil and selected AM fungal inoculum significantly improved survival of native species, but survival was species-specific. A second project tapped into the plant-soil feedback (PSF) framework to determine the reciprocal effects of interactions between plants and root-associated microbes. Previous research indicates PSFs driven by invasive plants can be buffered by management practices. Therefore, I investigated the influence of herbivory as a potential restoration tool. In a greenhouse study, PSF responses of cooland warm-season native and non-native grasses were examined to determine how herbivory (clipping) impacts PSF dynamics. My findings suggest herbivory alters the strength and direction of PSFs, and these changes may impact interactions of plants and associated soil microbes. Reintroducing herbivory into invaded areas may be a pathway to reset PSFs established by invasive grasses, potentially negating soil legacies by buffering the benefits established through soil microbial alterations.

Phenotypic plasticity is a widespread mechanism that allows animals to respond quickly to seasonal changes in their environment. However, the depth and complexity of these plastic responses is still being discovered. One aspect of seasonal physiology that is relatively unstudied is changes to sensory physiology and how it may explain changes in behavior. To determine how changes in seasonal conditions affect behavior, coloration, and vision, I examined populations of wild butterflies in Northwest Arkansas. Focusing on a single species, the common buckeye Junonia coenia, I found that seasonal coloration covaries with thermoregulating behavior and is accompanied by changes in visual genes in eye tissue. Investigating seasonal response at the community level, I found that as light increases, abundance increases and behavior changes among butterflies, though individual butterfly families differ in their responses to seasonal conditions. Changes in season and temperature had a greater effect on abundance than behavior, which is also affected by shifts in weekly precipitation levels. Lastly, I described sexual dimorphism in eye size and coloration in potential visual signals in J. coenia. I found that females are brighter with more wing ornaments than males. Males have larger eyes than females despite being smaller in body size. Developing in shade causes a sexually dimorphic part of the wing to reflect more ultraviolet wavelengths, which are important for male mate choice in this species. Together these results demonstrate the important role the seasonal environment plays in shaping behavior and suggest covarying changes in coloration and visual physiology may underly seasonal behavioral shifts.

A Collaborative Adaptive Management (CAM) Project was started at the University of Nebraska in 2020 to address some of the key uncertainties related to the management of grasslands in the Nebraska Sandhills through stakeholder driven experiments and the adaptive management cycle. Patch-burn grazing was selected by CAM as a management tool to generate heterogeneity across the landscape and promote biodiversity while balancing economic and ecological trade-offs. The patch-burn grazing system was implemented with controlled burns in May of 2022 and March of 2023. Other parties in CAM will be examining the impact that patch-burn grazing has on forage and livestock performance, and early results show an increase in the weight gain of cattle in the patch-burn grazing system. The goal of the research presented here is to understand how the use of patch-burn grazing impacts several ecological aspects of the Nebraska Sandhills. Specifically, this study asks three things 1) does patch-burn grazing negatively impact soil conditions by increasing soil erosion and depleting the thin topsoil of nutrients in burned areas, 2) is patch-burn grazing able to significantly change vegetation structure and promote vegetation heterogeneity, and 3) how does patch-burn grazing affect avian communities, their species diversity, and abundance in the Sandhills? The comparison of soil conditions between burned and unburned was made using erosion pins installed throughout the burned and unburned fields and a series of soil nutrient panels samples taken before and, in the months following the fire. Vegetation structural metrics and function group covers were measured throughout each field in the study. A nonmetric multidimensional scaling (NMDS) ordinal analysis supported by a pairwise comparison using permutational multivariate analysis of variance (PERMNOVA) was used to examine the difference in vegetation structure between each of the fields in this study. Bird point counts were performed in each field throughout the two years of this study. This data was used to calculate and compare species diversity, community composition, and the abundance of a few select species. NMDS and PERMNOVA were used to explore the differences between the avian communities in each field, while N-mixture models were used to estimate abundance. Patch-burn grazing proves it is able to change the vegetation structure of the Nebraska Sandhills to promote heterogeneity and create more habitat for a diversity of different grassland bird species without compromising soil health. This study provides an understanding of how patch-burn grazing, an under-utilized tool in the Nebraska Sandhills, can be used to support a more heterogeneous and resilient grassland. Advisor: Craig Allen

The federally threatened eastern massasauga rattlesnake (Sistrurus catenatus) occurs across the Great Lakes region of the midwestern United States in increasingly small and fragmented populations. While massasaugas are relatively well-studied among snakes, much is still unknown about their baseline habitat requirements, as well as how they move across heterogeneous landscapes. One of the most stable remaining populations outside the species strongholds of Michigan and Ontario is found at a wildlife area in northern Ohio.My research objectives were to: 1) identify land use practices and habitat features that best predict massasauga occurrence at the wildlife area; and 2) determine how the wildlife area is functionally connected for massasaugas given the amount of active agricultural production still taking place on the landscape and the species’ tendency not to travel great distances. During the 2022 field season, I used adapted-Hunt drift fence technique (AHDriFT) camera arrays and timed constrained visual encounter surveys to assess massasauga occupancy and created single-species integrated occupancy models to establish which covariates best predicted occupancy. Massasaugas were more likely to occupy sites with a higher proportion of open herbaceous habitat, sites with a higher proportion of marginal habitat features like infrequently mowed ditches and field margins, and sites that had been out of agricultural production for a longer time. I created a series of cumulative kernel density surfaces using three different dispersal kernels to analyze functional connectivity for massasaugas at the wildlife area. I also examined the potential impact of agriculture on connectivity by using three alternative resistance values for agriculture in the resistance surface. The probability of detecting dispersing massasaugas was highest in and around the heavily occupied center of the wildlife area. Using the mean rank for each of the 45 agricultural fields across the nine different density surfaces, I determined which fields dispersing massasaugas would most quickly encounter and potentially colonize if those fields were removed from agricultural production and restored. The results of these analyses will help facilitate effective and adaptive management for the northern Ohio wildlife area massasauga population and will offer valuable insight into how massasaugas traverse heterogeneous landscapes across their range

The Prairie Pothole Region (PPR) of North America is home to dynamic glacier-formed lakes and wetlands that range in size from small intermittent wetlands to large permanently filled basins. Predicting water-related shifts in environmental conditions and biological community responses within these systems has been challenging due to non-linear, scale-specific changes. Furthermore, landscape-level changes in the quantity and distribution of surface water are becoming more frequent. This thesis contributes to our understanding of how waterbody size, and potential size fluctuations, influence chemical and community dynamics of complex PPR glacial lakes and wetlands. We paired remote sensing and discontinuity methods with US Geological Survey long-term monitoring data to evaluate intrinsic waterbody size scales over multiple large spatial and temporal scales within North Dakota. Our first chapter assessed waterbodies in Kidder and Stutsman Counties, ND within 2012 to determine if abiotic or biotic dependencies exhibited linear, non-linear, or scale-specific patterns. Our second and third chapters assessed hydrological changes of wetlands in the Cottonwood Lake Study Area (CLSA), ND between 2009-2020 and potential biological shifts through time. We assessed the landscape for a hydrological regime shift and potential biological consequences. Additionally, we evaluated wetlands based on size to distinguish if communities varied between small (≤ 1 ha) and large (> 1 ha) wetlands. In waterbodies of Kidder and Stutsman Counties, we identified both linear (n=11) and scale-specific (n=9) patterns of water chemistry variables and scale-dependencies of fathead minnow (Pimephales promelas). The landscape of the CLSA experienced a hydrological shift between 2014 and 2015 (i.e., two regimes: 2009-2014, 2015-2020) and significant shifts in specific conductivity and macroinvertebrate and breeding bird communities. Over the eleven-year period a significant loss in small wetlands (≤ 1 ha) at CLSA was observed. Small wetlands were disproportionately affected by the drying period, and we also determined these wetlands (≤ 1 ha) support unique overall communities and specific taxa across multiple trophic levels compared to large wetlands (> 1 ha). This thesis demonstrates that remote sensing paired with discontinuity techniques can be a useful approach to assess lentic systems at multiple spatial and temporal scales.

Abstract: There has been an ongoing trend of increasing Canadian canola production, coinciding with increased intensity of canola in rotations. This contrasts with extensive research that has found significant agronomic benefits from less canola-intensive and more diversified cropping systems. Current producer behavior in terms of increasing frequency of canola in rotations is attributable to the short-term profitability of canola relative to competing crops, although other factors such as participation in business risk management (BRM) programs may also be relevant. Understanding the role that these factors play in determining risk efficient crop rotations is of importance to industry as well as to policy makers. This study examines the economic trade-offs for alternative crop rotations, through an evaluation of net returns from crop production for representative Alberta and Saskatchewan cropping operations in the Black and Dark Gray soil zones. Production and market risk are incorporated through modeling of stochastic processes for crop yields and prices. Farm-level benefits and costs of rotations are estimated using Monte Carlo simulation and Net Present Value analysis methods. SERF analysis is used to identify risk efficient rotations for different levels of risk aversion. A common cropping rotation, consisting of spring wheat and canola was designed as the base rotation for all representative farms, and alternative cropping systems examined in the study were varied in length, specific crops included (i.e., barley, oats, field peas, flax) and degree of diversification/specialization. Results suggested all rotations for all three farms generated significantly positive expected wealth, while more specialized crop production were more economically viable due to the shortterm economic benefits associated with specialization. The annualized per acre risk premiums required by producers to adopt more diversified crop rotations were approximately $34, $2.30, and $11 in Camrose, Smoky River and Saskatchewan, respectively. Further, SERF results also suggested the advantages of specialized rotations are reinforced by participation in BRM programs, with corresponding increases in the risk premiums required to adopt more diversified rotations. This confirms the role of BRM programs in supporting adoption of more specialized crop rotations by crop producers in the study regions. While including yield effects of previous crops in the rotation did not have a significant impact on results for the risk efficiency analysis, it did highlight the relevance of this type of information on the economic performance of alternative rotations and the benefits (or lack thereof) of more diversified rotations. Lastly, the results from this study support the argument that information on negative productivity factors (e.g., disease event incidence and severity) are needed to provide producers with the knowledge required to make informed cropping management decisions.

The bee community in Minnesota’s tallgrass prairie is doubly threatened. The conversion of prairie to agriculture and development has fragmented the landscape nearly beyond recognition. Over vast swathes of the state, single species exist in monocultures where once highly diverse grasslands grew. On top of this, bees across the continent face pressures from parasites, pathogens, and pesticides. The pockets of remnant prairie that persist are dependent on human-mediated disturbance. Grazing and burning, which can be seen as analogues to historic disturbance patterns, are effective and important tools in maintaining prairie health. Through this thesis, I seek to parse out the differing impacts of these two management techniques on bee communities and to explore how environmental characteristics impact the suite of traits bees display in remnant prairies.

A major constraint of beef production within the Standing Rock Reservation has been identified as a reduction in rangeland quality due in large part to wide-scale colonization by black-tailed prairie dogs (Cynomys ludovicianus). The desire exists within the community to design a holistic framework which incorporates livestock management with the goal of increasing production and rangeland health while still maintaining increased diversity associated with prairie dogs. Prairie dogs reduce the carrying capacity of cattle on rangelands by up to 50% on occupied hectares through direct consumption of vegetation and waste due to clipping to improve detection of predators. Livestock stocking rates that do not account for the level of prairie dog occupation can result in a reduction in animal performance and a further decrease in rangeland productivity due to overgrazing. Research is needed to understand season-long use of grazing cattle on and off prairie dog towns to better inform land manager decisions aimed at reducing over-utilization of grasslands and allowing higher production of livestock. This dissertation study was part of a larger study that was conducted in northcentral South Dakota from 2012 to 2016. This dissertation sub-study was designed to evaluate the impact of prairie dogs and cattle on plant community production and composition, and to determine impacts of colonization on livestock grazing behavior, diet quality, and forage intake. Three pastures with varying levels of prairie dog occupation (0%, 20%, and 40%) were studied. Pasture stocking rates were adjusted to account for the level of forage removed by prairie dogs (50%) on active colonies. Two study treatments were evaluated: Ecological Site (n=3) and grazing treatment (n=4). Ecological sites (ES) were Shallow Loam, Loamy, and Thin Claypan. Grazing treatments included two in off-town locations (non-graze (NG) and cattle only graze (CG)) and two in ontown locations (cattle and prairie dog graze (CPD), and prairie dog only graze (PD)). These treatments and their interactions were evaluated to determine their effects on vegetation (e.g. standing crop, diversity, species richness, etc.) and livestock (e.g. animal weight gains, diet quality and quantity, etc.) parameters. Goals of the dissertation herein are to understand 1) the interactions of prairie dogs and livestock on plant communities and 2) the impact of prairie dog occupation on livestock production. Objectives of this dissertation are: 1) Evaluate plant community response to grazing on and off prairie dog towns to determine how livestock and prairie dogs alter plant community production and composition; 2) Develop strategies that enable identification of plant communities of interest on and off prairie dog towns using remote sensing techniques ; 3) Develop methods to utilize programming tools for efficient processing of GPS collar data ; 4) Evaluate relationships between plant communities and cattle grazing locations to identify patterns and trends in livestock grazing behavior throughout the growing season; 5) Evaluate diet nutrient composition and intake by cattle on plant communities on- and off-town over the grazing season; 6) Develop a framework of cattle nutrient consumption in pastures with varying levels of prairie dog occupation; and 7) Synthesize existing research and results from this dissertation to explore potential synergism between prairie dogs and cattle on the landscape from a systems approach. Vegetation analyses show a significant difference in standing crop biomass between grazing treatments, with sites grazed only by cattle having 36% more biomass than those grazed only by prairie dogs. Plant community data suggest that prairie dogs have a greater impact on production and species composition compared to cattle; percent composition of C3 grasses was greatest off-town, whereas percent composition of C4 grasses was greatest on-town. An invasive C3 species of concern in the Northern Great Plains, Kentucky bluegrass, was almost non-existent on-town, but increased substantially off-town over the 5 years of the study for all ES; the most dramatic increase occurred on the Thin Claypan ES. Species diversity was not different between grazing treatments, however species richness was generally greatest on-town. Additionally, for the entire duration of the study (2012-2016), 46 species were only observed on-town and 17 only observed off-town out of a total 113 species observed throughout the 5 years of the study. The remote sensing analyses show that Random Forest (RF) models were highly effective at predicting different vegetation types associated with on and off prairie dog town locations (misclassification rates < 5% for each plant community). However, comparisons between the predicted plant community map using separate years indicate 6.7% of pixels on-town and 24.3% of pixels off-town changed class membership depending on the year. The results show that while RF models may predict with a high degree of accuracy, transition zones between plant communities and inter-annual differences in rainfall may cause instability in fitted models. An essential component of evaluating livestock behavior for this study was accomplished using GPG collars that record both location and activity. Traditional methods of hand-processing of GPS data require a large number of steps which are both time consuming and prone to errors. As part of this dissertation, methods were created to streamline the processing of livestock GPS collar data, resulting in a technical note publication. Due to the open source nature of Program R, custom functions can be created to merge GPS collar data, GIS data layers, and behavior algorithms to improve data processing efficiency. Plant communities of interest for the livestock behavior and intake components of this study were identified as grass-dominated on-town sites (PDG), forb-dominated ontown sites (PDF), and grass dominated off-town sites (NPD). Livestock behavior analyses from this study show cattle slightly prefer grazing on prairie dog towns, with shifts occurring to off-town locations over the duration of the grazing season. Crude protein (CP) content from diet samples for PDF sites were significantly greater than for PDG and NPD sites. Little difference in many of the diet metrics existed, however, between grass dominated sites (PDG and NPD). Despite higher CP content on forb dominated sites on-town (PDF), intake levels were depressed on these communities due to high bare ground and low vegetation production. Individual livestock performance (average daily gains) averaged over the entire length of the study, were 0.74 kg. /day for the 0% occupied pasture, 0.86 kg. /day for the 20% occupied pasture, and 0.85 kg. /day for the 40% occupied pasture. Reduced stocking rate in prairie dog pastures may have contributed to greater individual animal performance. Higher livestock performance for the prairie dog pastures is potentially due to access to a more diverse diet. Reduced stocking rates in prairie dog pastures, however, resulted in a reduction in overall livestock production in terms of kg / ha. At low levels of colonization in pastures, livestock may potentially benefit from increased diet selection, however, reduction in plant biomass on town may negate any potential gains at higher levels of colonization. The results from this study were combined to take a systems approach to understanding the impacts and interactions of prairie dogs and livestock on plant communities, and the impacts of prairie dog occupation on livestock production in northern mixed-grass prairie ecosystems. Our results indicate that having both on-town and off-town plant communities within a pasture can increase biodiversity and heterogeneity at broader landscape scales. Differences in plant community composition may increase diet diversity for grazing livestock, potentially benefiting individual animal gains, provided forage quantity is not limited. At low levels of colonization, livestock production may only be minimally impacted while still realizing benefits to biodiversity.

Social and genetic monogamy are social and mating systems that are influenced by numerous neurochemicals including dopamine, which is identifiable by the presence of tyrosine hydroxylase (TH). Previous research on TH has only been performed in laboratory experiments but never in a semi-natural environment. I released prairie voles Microtus ochrogaster descended from two populations into semi-natural environments and tracked their behavior with radio-telemetry and live trapping. Using immunofluorescence, I examined changes in the number of TH positive (TH-ir) neurons. Socially monogamous males had lower TH-ir within the medial pre-optic area (MPA) and the paraventricular nucleus (PVN) than non-monogamous males, however usually only in males from one population. Also, males that sired offspring with more females had more TH-ir within the bed nucleus of the stria terminalis (BNST). These results suggest that TH synthesis within the BNST is responsive to mating, whereas TH within the MPA and PVN may be more responsive to a combination of social and mating cues. There was no evidence that co-localization of the immediate early gene (IEG) fosB with TH-ir neurons was related to monogamy. This study suggests that, in semi-natural environments, dopamine is involved in expression of monogamy, although there were population differences.

There are many ways in which microbiomes can influence the health and fitness of their insect hosts. While much research has been done on the microbiomes of economically important species like honeybees, and charismatic groups like butterflies, little work has been done to understand the microbiome of grasshoppers and katydids. Grasshoppers are an important herbivore in grassland ecosystems and provide important ecosystem services like nutrient cycling. Alternatively, grasshoppers can be a pest organism requiring management and control. In relationship to the total ecosystem, the limitation of abiotic factors like essential nutrients can influence the abundance and fitness of insect herbivores such as grasshoppers. However, the effect of these abiotic factors on grasshopper microbiomes is largely unknown. Using culture-independent, high-throughput 16s and ITS sequencing and statistical analysis, we examined the gut microbiome of six species of grasshoppers (n=60) from the site of a fully-factorial fertilization experiment in a coastal tallgrass prairie ecosystem in order to gain a better understanding of the microbial communities present across the orthopteran order in this ecosystem. We also examined the relationship between environmental nutrients and gut microbes of one orthopteran species, Orchelimum vulgare. Our observations support the hypothesis that there is a “core” group of bacterial families in these grasshopper species and factors such as trophic behaviors and the evolution of the host may contribute to the shifts in prevalence among these core microbial groups. We also found significantly higher Shannon diversity in the gut bacterial communities of those grasshoppers from plots fertilized with added sodium in contrast to plots without sodium. There is significantly lower diversity in gut fungal communities from plots amended with nitrogen and phosphorus, as well as sodium, suggesting that both nitrogen and phosphorus and sodium are limiting nutrients for the fungal community. There was also a strong positive correlation between bacterial and fungal diversity within each sample. These results support the hypothesis that environmental nutrients will alter the characteristic gut microbiome of O. vulgare, though these alterations will be different for bacterial and fungal communities.

Monitoring land use and land cover (LULC) change and its effect on habitat availability and connectivity is crucial for species conservation and management. This is most efficiently accomplished at a sufficiently broad scale using remote sensing technology. Current approaches benefit from freely available data sources such as National Land Cover Database (NLCD), derived from 30 m Landsat imagery. However, temporal frequency and spatial resolution of NLCD may be insufficient for some applications. Specifically, 30 m resolution data may not detect small or narrow landscape features that may be important habitat for small animals such as amphibians. Other available data sources, such as the higher resolution (0.6-1 m) imagery obtained by the National Agriculture Imagery Program (NAIP), may be more suitable for detecting fine-scale features, but requires users to estimate their own landscape classifications to make the imagery useful for ecological analysis. The purpose of my study was to create LULC maps from NAIP imagery and estimate LULC change over a ~10-year period of a 24.2 × 21.7 km portion of North Dakota’s Prairie Pothole Region (PPR). I also used the classified NAIP maps to estimate changes in potential functional connectivity for amphibians based on hypothesized effects of land cover on their movement across the landscape. For both objectives, I compared estimates obtained from NAIP imagery to those obtained from lower resolution NLCD maps. I found that object-based image analysis (OBIA) of NAIP images (overall accuracy 88.4-93.2%; Kappa 0.840-0.901) classified the landscape more accurately than two pixel-based classification methods (overall accuracy 70.9-77.3%; Kappa 0.603-0.677) and produced more accurate maps than NLCD (overall accuracy 69.7-75.0%; Kappa 0.563-0.658) in the study area. From 2009 to 2018, cropland and wetland cover increased while grassland/pasture/hay and tree/forest cover decreased within the classified NAIP images. The increase in wetland cover corresponded with an increase in smaller, more closely positioned wetlands. However, wetland patches also appeared to become functionally less connected for amphibians, based on assumed relationships between land cover and constraints on movement. In contrast, NLCD maps estimated different overall LULC proportions and the opposite trend in potential connectivity. My research suggests that higher resolution data may be more suitable for assessing the landscape patterns and trends for small-bodied animals with limited mobility, such as amphibians.

Prairie Cordgrass (PCG) Spartina pectinata is a native grass to North America that survives saline conditions, can be harvested multiple times in a year, and can be used as biofuel. Endophytes are bacteria that reside in plant tissues and often have growthpromoting capabilities. They can assist plants by obtaining nutrients by improving the tolerance of plants against a broad range of stresses, such as plant pathogens, viruses, flooding, drought, acids, or bases. PCG can survive ocean levels of salinity. Endophytes that naturally bond with PCG may not only be able to not only help PCG but be transferred to other plants and confer the same salt tolerance to others. Several PCG plants from salt sites were harvested, and several possible endophytes were then tested for their ability to survive in salt solutions. Sixteen of the most promising endophytes were tested in three short term greenhouse experiments to determine their viability. Unfortunately, none of the endophytes tested outperformed the controls by statistical analysis, but there are endophytes that performed similarly to the controls in some metrics of the experiments. R3B Agrobacterium tumefaciens, L4A1 Bacillus haynesii, R4B1 Bacillus cereus, and R5A1 Bacillus pumilus were some of the best and the most valuable for others to test in future experiments.

Two experiments were conducted to determine the effects of replacing prairie hay and dried distillers grains plus solubles (DDGS) with whole cottonseed (WCS) in finishing diets balanced for physically effective neutral detergent fiber (peNDF) on animal performance, carcass characteristics, plasma metabolites (glucose, lactate, urea nitrogen, non-esterified fatty acids), and ruminal characteristics. In experiment 1, heifers (n = 103) and steers (n = 104) were blocked by BW within sex and allocated to 1 of 2 experimental treatments using a randomized complete block design (6 pens per treatment) with 17 (n = 10 pens) or 18 (n = 2 pens) animals per pen. Treatments included a control diet (CON; prairie hay, DDGS, dry-rolled corn, and liquid supplement), and a WCS diet (CTN; WCS, dry-rolled corn, and molasses). Both diets contained a vitamin and mineral supplement and urea at the same concentration. Cattle fed the CTN diet tendened to have a greater final BW (P = 0.10), had greater overall ADG, G:F, HCW, fat thickness, and USDA yield grade and had a more neutral fecal pH (P ≤ 0.05) compared to cattle fed the CON diet. The cattle fed the CON diet had a greater final fecal consistency score, plasma urea nitrogen (P ≤ .01), and tended to have a greater plasma lactate concentration (P = 0.06). In experiment two, 4 ruminally cannulated Holstein steers were randomly allocated to the 2 treatment diets from experiment 1. There was a treatment × time interaction for rumen fluid lactate (P = 0.0002) with the cattle fed the CON treatment having a greater concentration at h 2. Rumen fluid pH was affected by time (P = 0.02), but not treatment (P = 0.22). The cattle fed the CON treatment had a greater acetate:propionate ratio, butyrate, and valerate proportions (P ≤ 0.04) and had a tendency for a greater acetate proportions (P = 0.06). The cattle fed the CTN treatment had a greater propionate proportion (P = 0.03). These experiments suggest that WCS can replace the roughage and byproduct protein and fat source within a finishing diet while simultaneously resulting in increased growth and feed efficiency while maintaining an acceptable rumen environment.

Abstract: Grasslands ecosystems are increasingly subject to anthropogenic alterations, including conversion to cropland or tame pasture, and dissection by urban infrastructure. Linear disturbances, like roads, oil and gas pipelines, and electrical transmission lines, can fragment these ecosystems, directly alter underlying soils, and serve as vectors for plant invasions. A novel construction method, adapted from oil and gas extraction in the northern boreal forest, uses technology to redistribute equipment weight during construction in native grassland in an effort to decrease the footprint created from industrial development. The technology is comprised of an interlocking matrix of three-ply wooden mats, called access mats, used to create temporary road and work areas.This study was conducted on the University of Alberta’s Mattheis Research Ranch to examine the impact of various access mat placement treatments on native grassland of the Dry Mixedgrass prairie in SE Alberta, and reflected ongoing construction activities of ATCO’s Eastern Alberta Transmission Line, which was located nearby. Treatments were conducted in which the timing and duration of mat placement were varied from spring to fall, and from 6 to 24 weeks, on each of two ecosites (loam and loamy-sand), and monitored for up to 3 years of recovery. Main areas of focus were soil physical attributes, such as soil bulk density, penetration resistance, and water infiltration, along with nutrient supply rates, as well as vegetation responses such as biomass and nutrient components. Results of the field trials indicated traffic without mats (TWOM) increased soil penetration resistance (PR), while traffic with mats (TWM) initially had lower PR when mats were removed and soil moisture contents (SMC) two to three times the Control; however, SMC and PR within the TWM returned to Control levels six weeks after mat removal. Grass biomass was reduced under mats in place for 12 weeks or more compared to Controls in the first and second year (p = 0.0007) of recovery after treatment application. Introduced and ruderal forb biomass increased during first year of recovery (p < 0.0001). Biomass responses were more apparent on loamy-sand soils than loam soils. Light levels of traffic in this study did not create impacts that differed from the Controls for either grasses or introduced forbs under TWOM. Soil nutrient availability increased under TWM the year of treatment application relative to Controls; more specifically, nitrogen was ten times higher, sulfur double, iron four times higher, and manganese five times higher than those measured in the Control. Available soil nutrients quickly dissipated and led to levels similar to those of the Control by the following spring. Soil available nutrients under TWOM saw slight or no increase compared to Controls. Under the conditions of this study soil physical properties and vegetation were maintained close to those of the Controls under TWM when mats were in place for no longer than 6 weeks, while simultaneously mitigating the effects of wheeled industrial traffic. Results indicate that soil and vegetation recovery are influenced by the dominant soil texture as well as the season and duration of access mat use. Mats moderated soil compaction at the cost of vegetation biomass in placements longer than six weeks. Mats would be recommended to extend work time frame and possibly increase levels of traffic with consideration for the plant community underneath, and removal before plant death or with a revegetation strategy for recovery in place.

Abstract: The Sunset Prairie Formation is a newly established lithostratigraphic formation within the Middle Triassic (Anisian) of western Canada. The interval had commonly been overlooked or placed within the underlying Montney Formation or overlying Doig Formation, or was considered to be partially within the two formations. However, the Sunset Prairie Formation is sedimentologically, ichnologically and palaeontologically distinct from the overlying and underlying formations. The Sunset Prairie Formation is an unconformity-bound unit, characterized by interbedded pervasively bioturbated and diminutively bioturbated siltstone, fine-grained sandstone, phosphatic sandstone with locally abundant bivalves, gastropods, lingulid brachiopods, spiriferid brachiopods, terebratulid brachiopods, echinoid skeletal elements, and crinoid ossicles. Trace fossils present within the interval, listed from most abundant to least abundant, include Phycosiphon, Rosselia, Cylindrichnus, Teichichnus, Asterosoma, Scolicia, Helminthopsis, Palaeophycus, Chondrites, Planolites, Diplocraterion, Rhizocorallium, Thalassinoides, Skolithos and Zoophycos. Seven facies are identified in the formation and record deposition within the offshore, offshore transition and lower shoreface of a sheltered coastal setting. Facies stacking patterns exhibit up to three shoaling-upward parasequences. These parasequence exhibit a back-stepping or retrogradational stacking pattern, and are assigned to a transgressive systems tract. Structural features associated with the Western Canada Sedimentary Basin greatly influenced the deposition and preservation of the formation.The Sunset Prairie Formation is the first stratigraphic occurrence of a pervasively bioturbated interval that is regionally extensive following the end-Permian mass extinction in Western Canada. The unit provides a unique dataset to investigate physico-chemical stresses influencing the distribution of trace fossils, and thereby infaunal biota, within a marine realm during post-extinction faunal recovery. Through the comparison of process ichnology data (bioturbation intensity, burrow diameter, ichnodiversity, and Size Diversity Index) and geochemical proxies for redox-sensitive elements (Mo, V, and V/Cr) collected at a high-resolution (10 cm intervals), vacillating redox conditions are interpreted to have occurred during the deposition of the Sunset Prairie Formation. The recognition and investigation of the Sunset Prairie Formation provides new sedimentological, ichnological, palaeontological and geochemical evidence to unravel the palaeoenvironmental and palaeoecological transition from the Lower Triassic to the Middle Triassic within Western Canada.

The presence of diverse bee communities in an ecosystem is vital for maintaining healthy plant communities, promoting habitat resilience, and supporting sustainable agricultural production and urbanization. Approximately 20,000 known species of bees exist worldwide and assist with the successful reproduction of nearly 80% of Earth’s flowering plants by providing pollination services. In the US, wild bee declines have led to increased monitoring efforts for bees but there remain critical data gaps in prairies of the Great Plains ecoregion. Specific to the Tallgrass prairie where only 1-3% remains in native vegetation, the Nebraska Wildlife Action Plan has identified the loss of pollinators as a key stressor as well as a lack of sufficient data from which to monitor this stressor. This thesis seeks to 1) review current literature on the status of prairie ecosystems and the interdependency of wild bees, 2) establish and describe baseline data on wild bees and flowering forb communities, and examine their existing interactions in southeastern Nebraska Tallgrass prairies, 3) assess how the variation in vegetation cover influences the richness and abundance of wild bees, and 4) provide an extension guide highlighting a bee’s role in conserving the biological diversity of prairies. Over a period of 2 years, 85 species of wild bees and 114 species of flowering forbs were identified, and a preference index was calculated (based off of the abundance of bee visits to observed flowering forbs) to improve pollinator seed mixtures and inform future restoration efforts. Additionally, this thesis presents evidence that newly-restored prairies seeded with high diversity mixes support higher richness and abundance of wild bees compared to remnant prairies, however remnant prairies provide consistent support to wild bees on a temporal scale. Collectively, the resulting information of this thesis will aid in the design, management and reconstruction of the Prairie Corridor on Haines Branch (Lincoln, Nebraska) by providing recommendations tailored to enhance and sustain diverse bee communities. Advisor: Judy Y. Wu-Smart

The increasing negative effects of human impacts on the Earth have led to the urgent need for large-scale ecological restoration. One ecosystem of particular interest for restoration is tallgrass prairie, which only has 4% of its original 167 million acre range remaining in North America. However, restored and constructed prairies often do not support the same biodiversity and ecosystem services as remnant prairies. Many restoration projects only focus on reinstating vegetation, assuming that other trophic levels will colonize on their own. These higher trophic levels include arthropods, which make up a majority of the biodiversity in prairie ecosystems. We sought to determine if there is a difference in the insect communities in constructed and remnant prairies. It was hypothesized that insect communities would be different, with higher arthropod abundance and diversity in remnant sites, and older constructed sites would more closely resemble remnant sites. It is possible that indicator species of high-quality prairie could be identified, and that they may possess certain functional traits (morphological or life history) that allow them to colonize these sites. Sweepnet samples (100 sweeps per site) were taken at 5 old fields, 5 constructed prairies, and 5 remnant prairies in 2017, and 7 constructed prairies and 6 remnant prairies in 2018. All arthropods were then sorted to order, and some orders to morphospecies.The only order of insects whose abundance was significantly different between habitat types was Coleoptera (p = 0.041), which were 3.5 times more abundant in remnant sites than constructed sites. The only family of Coleoptera whose abundance was significantly different between habitat types in 2017 was Phalacridae (p = 0.046) which were 7.6 times more abundant in remnant sites than constructed sites. The abundance of Phalacridae in constructed prairies increased with age since construction (p = 0.03, R² = 0.63; p = 0.09, R² = 0.47). Ordinations of beetle families show that certain families are not being restored soon after the project, but rather restored slowly over long periods of time as late-successional species are able to colonize, such as Phalacridae. These results could have large implications on how tallgrass prairies are restored and managed, and how these ecosystems should be assessed for restoration, specifically looking at other aspects of the ecosystem other than vegetation.

Black-tailed prairie dogs (Cynomys ludovicianus) are native burrowing rodents that occupy large areas in the shortgrass and mixed-grass prairies of the Northern Great Plains. They are an important component of these prairie systems due to their impacts on plant communities. Currently State-and-Transition models (STMs) for grassland Ecological Site Descriptions (ESDs) address grazing by livestock as a major factor affecting states and phases within states. Impacts from other grazers, such as prairie dogs, are either not addressed directly, or are included only in a transition to a generalized early seral state. There are, however, dramatic differences in plant communities within prairie dog towns associated with time of prairie dog occupancy as well as other biotic and abiotic factors. These differences are not captured by current STMs. For managers who are tasked with managing prairies occupied by prairie dogs, current STMs do not provide the needed conceptual framework for understanding spatial variation and temporal changes to grassland vegetation affected by prairie dogs, nor do they provide information on management practices and strategies needed to manage these lands effectively. This study was conducted in Custer State Park in southwestern South Dakota. The goal was to develop a state-and-transition model for prairie dog towns on the Loamy Ecological Site (ES) in Major Land Use Area (MLRA 62). Cover data of plant species was collected on and off of prairie dog towns in 2014 and 2015. These data were used to identify 5 distinct vegetation states associated with prairie dog colonies using a combination of Nonmetric Multidimensional Scaling (NMS) Ordination and Cluster analysis. The 5 states are: State 2, Native Invaded; State 3, Kentucky Bluegrass Dominated; State 4, Shortgrass Sod; State 5, Early Seral; and State 6, Fringed Sage Dominated. These 5 states are influenced by the interactions of fire, grazing by prairie dogs and large ungulates, presence of invasive plant species, and climatic factors (e.g. wet/dry cycles and temperature), all of which were used to describe transition pathways between states and community pathways within states. The resulting prairie dog stateand- transition model allows managers to determine the status and health of plant communities on prairie dog towns on the Loamy ES in MLRA 62. It will also help land managers understand vegetation variations across colonies, identify early warning signs that an undesirable transition is likely to occur, and provide potential restoration options that might be able to return a site to a more desirable plant community for management purposes.

All animals engage in aspects of social behavior at some time in their lives, whether through mating, territory defense, or more complex sustained cooperative behaviors. Therefore, the study of social behavior allows researchers to understand the large variability in the affective valence, length, and biological relevance of interactions among dyads or groups of conspecifics. This dissertation examines several aspects of social behavior (such as space use metrics and the number and strength of social contacts) across populations of a socially monogamous mammal, the prairie vole (Microtus ochrogaster). Throughout this research, I aim to understand and clarify the external and internal influences of among- and within-individual variation in close social contact behavior. Traditional methods of recording social behavior in small mammals, including live trapping and radio-frequency identification (RFID), are unable to track direct interactions or the day-to-day temporal dynamics of social relationships. Therefore, in Chapter 2, I first developed a novel biologging method to improve the temporal resolution of social behavior data collected in field settings with populations of small mammals. I compared the social behavior of free-living prairie voles as recorded by proximity loggers that detect direct interactions, live trapping, and RFID. I found that the use of proximity loggers for collecting social contact data increased the resolution of data (measured as the number of observations of an individual, social contacts recorded, and the strength of those social contacts) beyond that collected through traditional methods. In addition, I found that the proximity loggers recorded information consistent with patterns of spatial and temporal overlap among voles, as measured by live trapping and a passive monitoring technique. I conclude that the accessibility of proximity loggers for studies of behavior in small mammals offers a promising method for improved understanding of their social behavior and its dynamic nature. In Chapter 3, I used live trapping and a passive monitoring technique to investigate influences on social behavior in prairie voles. I compared the non-mutually exclusive hypotheses that aspects of the social environment drive social affiliation among individuals, that abiotic aspects of the physical environment drive social affiliation among individuals, and that individual traits of each vole drive their social behavior. I found that aspects of the social environment—specifically, adult sex ratio and adult population density—most reliably predicted metrics of social behavior for my study populations of prairie voles. My results indicate that aspects of demography and sociality are most influential on patterns of close social contact in this species, rather than seasonal factors. These findings add clarity to our understanding of prairie vole social behavior and help explain the behavioral variation that has been observed among populations of prairie voles for decades, by directly comparing the hypothesized influences of close social contact behavior. Finally, in Chapter 4, I explored the effects of laboratory breeding on outcomes of field studies, during which laboratory-bred animals are released into semi-natural enclosures. Despite finding quantifiable differences among the groups of founding voles used to populate the enclosures for our studies, I found only weak evidence for differences in their natural behavior. Instead, my findings are consistent with environmental influences on social behavior. These results demonstrate that, in contrast to laboratory studies of inbred animal strains, differences in laboratory breeding colonies do not significantly alter the outcomes of enclosure studies.

Soil microbial communities are affected by many factors, such as soil nitrogen (N) and the quantity of grass-root exudates, changing seasons, fertilization method, plant diversity, and their origin. This holds for both natural and fertilized soils. This research was intended to expand the current understanding of soil microbial interactions associated with ecological functions. The objectives of the research were (I) to characterize prokaryotic soil communities, estimate functional potential, and quantify nitrogen cycle-associated prokaryotic gene expressions across three phases of the growing season, (II) to explore the diazotrophic community composition in a natural system using nifH sequencing as well as 16S rRNA gene-derived N-fixing genera, confirm in-situ 15N2 incorporation by soil microbes and map N-cycling activity of soil bacteria using meta-transcriptomics, (III) to identify shifts in prokaryotic and fungal communities and prokaryotic nitrogen cycling potential in the soil amended with novel controlled-release fertilizers, and (IV) to verify nifH gene in cultured diazotrophic isolates from natural prairie soil and study their ability to promote the growth of Bromus inermis. Bacterial community composition was characterized using the V3-V4 of the 16S rRNA gene, and QIIME2, and PICRUSt2 were used to tease apart functional inferences. The N-cycle gene and transcripts were quantified using a high-throughput pre-optimized assay and nitrogen cycle evaluation (NiCE) chip. Diazotrophic and fungal communities were studied using the nifH gene and ITS1 sequences, respectively. Moreover, an in-situ nitrogen-fixation study was performed using a stable isotopic 15N2 incorporation assay. Also, meta-transcriptomic research was done to map the bacterial activity towards Ncycling in the areas devoid of legumes. Surprisingly, the nitrogen cycle genes and transcript quantities were largely stable and unresponsive to seasonal changes. Similar trends were seen in the bacterial community and their predicted functional potential. Furthermore, the bacterial community derived from nifH and 16S rRNA gene showed diversity in diazotroph communities in the prairie. In contrast, the qPCR and metatranscriptomics showed that soil microbes did not actively participate in nitrogen fixation. Furthermore, high-yielding biochar controlled-release nitrogen fertilizers (BCRNFs) caused minimal shifts in soil fungal and microbial communities. This suggests that they can be an excellent alternative to nitrogen fertilizer without affecting the soil microbiota. Unfortunately, the diazotrophs could not support the growth of smooth bromegrass despite multiple attempts to help them sustain in a sterile sand matrix. Thus, this research work provides insights into the potential application of characterized soil communities and functional capabilities to be used for the development of agricultural practices or environmental restoration.

On Being Dirt explores the dualities of intimacy and landscape, drought and flood, loss and finding, emptiness and wholeness all while attempting to move forward. These poems let go of the idea of what we think we want and reach toward devotion. Through invention and reinvention, Jacobs wants to show the reader soil and everything of it. On Being Dirt lets vulnerability come out but doesn’t completely give it while the speakers of these poems let go and confess but also maintain mystery. Jacobs abandons everything through aubades, pastorals, still lifes, elegies, and ekphrases to find the rawness and the vulnerability on which these poems inevitably land. While remaining poems of the prairie, this collection also asks what it means to relearn the self in a new place and acknowledges the unavoidable return to the soil. Through association with land and nature, On Being Dirt is an idea of what it means to be one.

“or to be eaten alive'' is a multimedia exhibition in which I merge my own coming of age story with a mythological ecology. In this work I reclaim my queer identity by communing with my past selves in a fantasy world created through the lens of Queer Ecology and Queer Eco-Futurism. The visuals in this exhibition obscure reality. They are abstractions of the landscapes I occupy—particularly the Tallgrass prairie and Ozark ecoregions. Through a speculative, fantasy world the exhibition introduces moments of adoration, death, fracturing, growth, joy, and failure. I form, draw, color and arrange the work embracing mistakes and flaws of creation, defying the idea that we must live in a way that is close to a divine perfection. Instead, I redefine divinity as acceptance, imperfection, and mystery. The title, “or to be eaten alive,” asks about choices of fate: Can you run away forever, or will you be eaten alive? What are the consequences of my desire and search for belonging? Additionally, the title of the exhibition also references the visual components of the work in the exhibition, which features fantastical monsters eating, biting, purging, transforming, entangling, caressing and kissing one another. I present the viewer with decadent, colorful, playful, and repaired ceramic sculpture, soft sculpture, drawings, books, sound, animated video projection, and performance. In this immersive, fantastical ecology, the viewer experiences my transformation in an afterlife where I- through fantasy- embrace my past self. Advisor: Margaret Bohls

The Oak Openings Region of Northwest Ohio is well known for its rare plant and animal species. It contains the few remaining wet prairie ecosystems in the area. Wet prairies are highly sensitive to changes in temperature and precipitation patterns as they are reliant on shallow groundwater to maintain a high water table during parts of the year. A study at a small watershed in the Oak Openings Region was conducted to determine if a computationally efficient machine learning approach could model the temporal response of shallow groundwater levels to changes in precipitation and other available weather data. Three years (May 2015-May 2018) of hourly water table data from a data logger located within a piezometer and hourly precipitation, temperature, relative humidity, and wind speed from the Toledo Express Airport weather station were used as inputs. An artificial neural network NARX (Nonlinear AutoRegressive model with eXogenous inputs) was built with a combination of input delay, feedback delay, and hidden layers. The model was tested with hourly and daily data. Results obtained an R2 of 0.82 and 0.86 for hourly and daily data respectively. The model was recalibrated to predict water table levels for drastic and less drastic climate change case scenarios. The model was able to show an expected shift in the response of the water table levels in the fall. This model could be used by land managers to better understand and also to predict changes in the hydrology of the wet prairie in the Oak Openings Region.

The eastern spotted skunk (Spilogale putorius) is a species of conservation concern in many portions of its range and has experienced a decline since the early to mid-1990s. However, little is known about the subspecies that inhabits peninsular Florida, the Florida spotted skunk (S. p. ambarvalis), which may still be abundant. To gather more information on this diminutive carnivore's ecology and to clarify its role as a predator of the endangered Florida grasshopper sparrow (Ammodramus savannarum floridanus), we conducted studies in 2016 and 2017 on the den site selection and diet of Florida spotted skunks in a dry prairie ecosystem in central Florida, where these 2 species co-occur. For the den site selection study, we tracked 36 individual skunks to 757 den sites and measured the habitat and den characteristics of these sites. Den sites were most often located in mammal burrows (61.6 %), followed by above-ground sites (35.5%), gopher tortoise (Gopherus polyphemus) burrows (1.5%), depressions (1.2%), and hollow logs ( < 0.3%). Each of these used sites was compared to a paired, random available den site using discrete choice analysis. We found that male and female nonbreeding skunks at our study site were 5 times more likely to select a mammal burrow over a tortoise burrow and that the relative probability of selection of a den site increased by 45% for each 1-burrow increase in the number of nearby burrows. Similarly, breeding female skunks selected mammal burrows and shallow depressions over gopher tortoise burrows by 16- and 13-fold, respectively, and relative probability of selection of a den site increased by 75% for every 1-burrow increase in the number of nearby burrows. Our findings suggest that den characteristics may be more important than habitat characteristics to Florida spotted skunk den site selection in dry prairie and that skunks in this ecosystem may be habitat generalists. For our diet study on this subspecies, we collected hair samples from skunks and tissue samples from potential food items across our study site. We subsequently conducted a stable isotope analysis to determine which food items comprised the Florida spotted skunk diet at our site. Our results suggested that skunks in the dry prairie have an omnivorous and generalist diet, as no food item groups composed a majority of their diet. The most prevalent food items in our study were millipedes (~27%) and insectivorous amphibians and reptiles (~25%). Insectivorous birds, like the grasshopper sparrow, comprised no more than approximately 15% of the skunk diet at our site. Overall, these studies contribute to the knowledge of Florida spotted skunk ecology and help elucidate the skunk’s role as a predator of grassland birds in dry prairie ecosystems, while also providing some recommendations for land managers to consider for reducing predation pressure on grasshopper sparrows by these skunks. However, this research should be expanded upon to better discern Florida spotted skunk diet composition and selection, and to determine if the patterns observed in our studies on diet and denning ecology hold in other portions of this subspecies’ range.

Field studies can greatly enhance our understanding of mechanisms that mediate social behaviors. Laboratory experiments indicate that relatively low expression of estrogen receptor alpha (ERa) in the medial amygdala (MeA) of the brain is linked to behaviors indicative of social monogamy in male prairie voles (Microtus ochrogaster), but this has not been examined in a field setting. I tested the hypothesis that ERa expression in the MeA influences sociosexual behaviors of male prairie voles in an ecologically relevant setting. I created replicate, semi-natural populations of prairie voles during 2015 and 2016 and monitored their behavior for 15 weeks. Males were bred for contrasting ERa expression in the first experiment and RNAi was used to inhibit ERa in half the males for the second. Although I detected little difference in males’ behaviors in the first experiment, I found that males with lower ERa had stronger associations with one female, smaller home ranges overlapping fewer females, and greater home range overlap with one female than males with higher ERa in the second experiment. These findings suggest that ERa in the MeA is an ecologically relevant mediator of sociosexual behavior and may be important in the evolution of monogamy in the prairie vole.

The Prairie Pothole Region (PPR) of North America is the tenth largest wetland ecosystem in the world. In Chapter 1, an overview of this region is provided, focusing on key biogeochemical aspects of this region. Additionally, themes explored throughout this document, such as sulfate reduction, methanogenesis, the role of viruses in biogeochemical cycles, and microbial alcohol metabolism, are briefly reviewed.Chapter 2 presents the first study of coupled geochemistry and microbiology in wetlands within the PPR, extremely high methane emissions, and the highest sulfate reduction rates measured to date. Our results also highlighted the dynamic spatiotemporal changes that occur in microbial communities and organic carbon pools in these sediments. Particularly, millimolar concentrations of ethanol and isopropanol measured in spring samples became depleted over summer. These surprising observations and measurements stimulated the detailed investigation of microbial community members, potential factors controlling biogeochemical processes, and key intermediates in organic matter degradation that are presented in the following chapters.Chapter 3 investigates which microorganisms are likely responsible for sulfate reduction and methanogenesis, investigating viral and metabolic controls on activity rates. From hundreds of recovered marker gene sequences and metagenome-assembled genomes, we identified phylogenetic and metabolic diversity in candidate sulfate reducers and methanogens, which had the inferred capability of utilizing the abundant alcohols measured in our first study, as well as methylated compounds and small organic molecules. Viral sequences were novel and abundant, and were predicted to target abundant candidate sulfate reducers and methanogens. We suggested that the inferred genomic diversity and metabolic versatility, viral infections, and niche differentiation likely play an important role in modulating carbon and sulfur cycling in this ecosystem.Chapter 4 explores how alcohols measured in high concentrations in PPR wetland sediments could be generated. We constructed an alcohol dehydrogenase (ADH) phylogenetic tree that allowed us to infer the substrate preference of ADHs present in genomes of candidate alcohol-cycling microorganisms. We identified 62 genomes from 16 phylum-level groups which had potential for alcohol cycling, including 14 genomes encoding putative isopropanol dehydrogenases. Moreover, we performed a detailed investigation of pathways accounting for alcohol fermentation. The potential for acetone/isopropanol-butanol-ethanol fermentation was not clear, and the role of putative isopropanol dehydrogenases in these genomes deserves further investigation. These results are the first insights into alcohol production in Prairie Pothole wetlands and represent an exciting new venue of research in wetland carbon cycling, with important biotechnological applications.Chapter 5 summarizes the main findings, conclusions and implications of this research, discussing questions that need to be addressed in future studies. Particularly, we concluded that metabolic versatility at both the organism and the microbial community level may be one of the key mechanisms underlying the high production and emissions of greenhouse gases in Prairie Pothole wetlands. Our results have implications to a variety of analogous terrestrial and marine environments and advance the field of wetland microbiology and biogeochemistry, providing insights that may be integrated into future climate change models.

Historically, disturbances shaped prairie ecosystems both directly through events like fire and soil moving by animals, as well as indirectly through dynamic rainfall patterns and periodic flux in seed availabilities. We hypothesized that the implementation of several distinct disturbance events in Nebraska Sandhills upland prairie would have measurable effects on plant community composition. We implemented mid-spring fire, soil disturbance in the form of disking, seed addition of native forbs on disked plots, as well as early summer supplemental watering (to mimic minor rainfall events during abnormally dry periods) during 2016 and 2017. Plant community response during the first and second growing season post-disturbance was quantified through measurements of June forb density as well as August percentage cover and herbage mass. In the first season, fire increased the cover of warm-season rhizomatous grasses as well as perennial forbs, such as western ragweed (Ambrosia psilostachya DC.), and reduced the cover of annual forbs and species richness. Fire had positive interactive effects on the cover of warm-season grasses in both seasons and on forb density in the second season. Perennial forb seedling establishment from spring seed addition was poor, possibly due to species-specific dormancy and abnormally dry June conditions. Seed availability did play a minor role on cover of seeded leguminous species, although temporary and year-dependent. Water addition (two 0.64-cm events) and burning, however, improved seeded forb establishment. Disking had generally negative effects on plant cover. Minor water additions had both positive and negative interactive effects on various species, with the underlying drivers of this often unknown. We documented ecological interactions between disturbance events, as fire mediated the negative effect of disking on warm-season grasses and water mediated its negative effect on grasses as a whole. Overall, distinct disturbance events significantly altered plant composition of Sandhills prairie over two growing seasons. Advisor: John A. Guretzky

There are only two natural ways by which molecular nitrogen can be available to support life, either by free-living or by symbiotic nitrogen fixing bacteria. The best studied diazotrophs form symbiotic associations with plants, primarily legumes and certain tree species, but little is known about how non-leguminous plants such as grasses obtain nitrogen in their environment. Natural prairies have few legumes, thus have less symbiotic nitrogen fixer interaction. This indicates presence of free-living nitrogen (FLN) fixation activity towards the balance of the N cycle. The objective of this study was to characterize the culturable diversity of free-living diazotrophs in native prairie. I isolated bacteria using Nitrogen Free Medium (NFM). Bacteria growing on NFM were subcultured with repeated steps to obtain single isolates. The phylogeny tree of 458-putative diazotrophs was determined using the 16S rRNA gene. The PolF/PolR primer set was used for nifH PCR to confirm the presence of nitrogenase, required for the reduction of molecular nitrogen to ammonia. Due to poor performance of multiple nifH primer sets various approaches to improve amplification efficiency were evaluated focusing on addition of Dimethyl Sulfoxide and Bovine Serum Albumin, and glycerol alone or combination. Of 458 putative diazotrophs, 96 yielded nifH by PCR. The sequences were analyzed using ARB and R. High diversity was found among FLN fixers, including alpha-, beta-, and gamma – Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria, but the largest group were Streptomyces. Out of 115 Streptomyces, 40 yielded nifH amplicons aligning with those of unrelated taxa such Mesorhizobium, Paenibacillus, and Herbaspirillium. Whole genome sequencing of three Streptomyces revealed presence of Bacillus, indicating co-culture. Purity of the isolates obtained was confirmed using phylum-specific 16S rRNA gene primers for Actinobacteria and Firmicutes as well as alpha and beta – Proteobacteria. This revealed that many of the putative pure cultures had a second strain belonging to a different phylum. In conclusion, there is a considerable diversity in the free-living nitrogen fixing bacterial community in prairie soil. Additionally, our data indicate apparent bacterial bi-cultures associated with nitrogen cycling. These findings could help us understand the dynamics of nitrogen cycling in naturally sustained prairie grassland ecosystem.