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Item Effect of professional development on teachers' understanding of interdisciplinary earth science concepts(Montana State University - Bozeman, College of Letters & Science, 2023) Huffman, Sue Ellen; Chairperson, Graduate Committee: C. John GravesThe Critical Zone describes the interactions that support life on Earth among the biosphere, geosphere, hydrosphere, and atmosphere. To truly understand the complex processes, scientists must look outside their immediate focus: geologists, biologists, hydrologists, and physicists collaborate to see how their research fits together. Teachers can do the same and use critical zone concepts to bridge across subjects and from the classroom to the real world. Unfortunately, K12 teachers may not have the requisite knowledge or research experience to feel confident in incorporating critical zone topics into their classes, and professional development services provided by scientists may not properly meet those needs. A three-day professional development program, the result of a collaboration between a research group, Critical Zone Network Drylands Hub, and a non-profit science center, Insights Science Discovery, was developed to support teachers with including place-based, cross-curricular instruction. This mixed-methods study aimed to measure the impact on teachers' knowledge of the related concepts and their confidence in teaching it. Teachers were assessed, surveyed, and asked to draw an image or mental representation of the critical zone model and identify related academic disciplines. Both teachers and contributing scientists were surveyed to learn how their motivations for participating in professional development compared to one another. Mental models increased in their complexity and accuracy of CZ components. This result, combined with a modest improvement in their performance on assessments and a substantial increase in confidence towards including CZ concepts in their curriculum, could indicate that the PD successfully impacted teachers and actions in the classroom. Surveys also revealed that teachers and researchers share many of the same motivations for participating in PD. Ultimately, both groups shared that contributing scientists could be better informed about the teachers' context and needs, making PD content more relevant and applicable to better support student motivation and learning.Item Dam removals: an agricultural analysis(Montana State University - Bozeman, College of Agriculture, 2024) Bush, Nathan Alexander; Chairperson, Graduate Committee: Melissa C. LoPaloDam removals are occurring with increased frequency throughout the United States. 77% of all dam removal projects in U.S. history have occurred in the 21st century and the number of dams being removed each year is rising. Dams often play a key role in agricultural production, making it important for agricultural producers and policymakers to understand the effects of these removals as they become more common. This paper explores the causal effects of dam removal on agricultural productivity in the United States using a two-way fixed effects event study and an instrumental variable framework. Primary results of the analysis are mixed and differ based on exact specifications used but show initial evidence of per acre crop productivity increases and cash receipt declines following a removal. Further research is needed to explore the fine-scale effects of dam removals on individual agricultural producers and to expand on the preliminary causal relationships observed in this paper.Item In-nii (Bison bison L.) reintroduction to Amskapiipikini (Blackfeet) Nation homeland: relationships with ksahko (soils)(Montana State University - Bozeman, College of Agriculture, 2022) Tatsey, Latrice Dawn; Chairperson, Graduate Committee: Anthony HartshornIn-nii (American Bison) are returning to their Traditional Territories after being nearly wiped out of the Great Plains of North America and Canada. The in-nii are slowly returning to Native American tribes who have the resources to run reintroduction programs like that of the Amskapiipikini (Blackfeet). This in-nii reintroduction presented an opportunity to look at the effects of the return of in-nii to the Amskapiipikini, and what their influences might be on the soils, plants, and water resources of the Blackfeet Nation. This research project was conducted on the Blackfeet Buffalo (In-nii) Ranch and the adjacent RRJ Cattle Ranch, comparing the influence of in-nii and cattle on soil nutrient cycles and soil carbon dynamics. Soil samples were taken from locations on the landscape that were near water sources on lower elevations, mid hillslopes for mid-elevation sites and on hilltops at higher elevations. Soil characteristics included soil organic matter (SOM), nitrate, pH, cation exchange capacity (CEC), and exchangeable calcium, potassium, sodium, and magnesium. Only two (CEC, magnesium) appeared to have been influenced by in-nii and cattle. The remaining soil characteristics were little influenced by grazer type. Substrate-induced respiration was also measured in the lab to see how microbes decomposed SOM (carbohydrates and other molecules) to release energy and CO2; we found no evidence of differences between in-nii- and cattle-influenced soils. Finally, we measured field respiration rates and water infiltration rates at multiple fence line sites; field soil respiration rates increased when soil had water infiltrated after the dry readings, soils also increased the time to absorb water after the first infiltration tests were run. Our preliminary results suggest that the reintroduction of in-nii to these lands has not yet resulted in measurable differences in soil-related properties of the Blackfeet Nation. Even so, the return of the in-nii for the Amskapiipikini is also about understanding the importance of using cultural science when studying the ecology of a system. Doing this can create an understanding of the traditional ways of knowing while bringing cultural healing and restoring connections between Amskapiipikini, in-nii, and land.Item Aquatic invertebrate colonization as a river restoration success criterion: a case study of the upper Blackfoot mining complex superfund site(Montana State University - Bozeman, College of Agriculture, 2023) Deyoe, Matthew Len; Co-chairs, Graduate Committee: Anthony Hartshorn and William KleindlIn 1975 the Mike Horse Dam partially collapsed, releasing 200,000 tons of cadmium, copper, iron, lead, manganese, and zinc into the streams and floodplains on the Upper Blackfoot Mining Complex (UBMC) in Montana, USA. The magnitude of the material that was toxic to humans from this event triggered the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), which currently governs 1,329 sites across the USA. Portions of the $39 million lawsuit in 2008 with the American Smelting and Refining Company (ASARCO), funded the remediation and restoration of 37 hectares of floodplains, wetlands, and stream channels. Although CERCLA's success criteria focus on reducing risk to human health from hazardous substances, the Montana Natural Resource Damage Program was interested in aquatic invertebrate colonization of the restored river ecosystems, since they are monitoring progress of restoration. To answer this, I explored whether observations of invertebrate colonization could gauge restoration success and identify aquatic invertebrate-based tools for future restoration projects. Over three years, I compared invertebrate communities at five impacted "restored" sites on the UBMC with ten unimpacted "reference" sites. I then quantified colonization using seven indices: four statistical taxonomic diversity and similarity indices, the River Invertebrate Prediction and Classification System (RIVPACS), the Benthic Index of Biotic Integrity (B-IBI), and a new Stable Isotopic Colonization Index (SICI) which estimated isotopic complexity using metrics derived from delta 15N and delta 13C stable isotopes. Statistical diversity and similarity indices showed the restored sites were diversifying quickly. For example, from 2020 to 2023, the average (+ or - 1SD) Shannon Diversity of restored sites increased from 1.1 + or - 0.5 to 1.8 + or - 0.43 while reference was 2.1 + or - 0.3. The average B-IBI of restored sites increased from 11.1 + or - 4.8 in 2020 to 31.7 + or - 7.7 in 2023 while reference B-IBI was 65.7 + or - 4.5, indicating ongoing ecosystem recovery, but this index required taxonomic identification to the genus level. The average SICI for restored sites was 23.3 + or - 6.1 and reference was 54 + or - 9.2, and SICI required identification to the family level. Restoration efforts on the UBMC have resulted in a promising trajectory, but continuous monitoring is imperative to ascertain if restored streams have reached reference conditions.Item Environmental drivers of bee community diversity in Yellowstone National Park(Montana State University - Bozeman, College of Letters & Science, 2022) Switzer, Kristen Ann; Chairperson, Graduate Committee: Laura BurklePollinators are essential to their ecosystems and facing large declines. Studies on environmental drivers of bee community composition are currently lacking in North America, particularly in national parks. Understanding how bee diversity and plant-bee interactions change across environmental gradients gives us insight into the resilience of bee communities in the future. We collected data at seven sites across an elevational gradient in Yellowstone National Park. Pan traps were used to collect bee diversity data from in 2010, 2011, 2012, and 2020, and hand-netting was used to collect plant-bee interaction data from June to August 2020. We hypothesized that elevation would be a major driver of bee abundance, species richness, and community composition and that bee diversity would decrease as elevation increased. We predicted bee diversity would peak in the middle of the growing season in response to floral diversity peaking at that time. Finally, we predicted plant-bee interactions would be more generalized at higher elevations and flower species richness would be a major driver of network specialization (H2'). Our results revealed that seasonality and elevation were major drivers of bee abundance and species richness, indicating that both spatial and temporal factors are important in driving bee community patterns. Bee species richness was highest in 2010 and declined over years, which may signal that changing environmental conditions are stressing bee communities. Bee abundance and species richness declined as each growing season progressed, which aligns with broader literature on various taxa and mirrors seasonal flower diversity patterns. Despite close alignment between bee and floral diversity patterns, flower species richness was only a significant driver of bee community composition, indicating that other environmental gradients were bigger drivers of bee abundance and species richness patterns. Bee species richness was a significant driver of plant-bee network specialization and elevation, slope, and flower species richness were marginally significant, suggesting that plant- bee interactions are influenced more by spatial than temporal variables. Additional studies focusing on bee diversity across growing seasons and years could provide insights into how changing environmental conditions in the future may influence bee diversity and community resilience in Yellowstone National Park.Item Bayesian hierarchical latent variable models for ecological data types(Montana State University - Bozeman, College of Letters & Science, 2022) Stratton, Christian Alexander; Chairperson, Graduate Committee: Jennifer Green and Andrew Hoegh (co-chair); This is a manuscript style paper that includes co-authored chapters.Ecologists and environmental scientists employ increasingly complicated sampling designs to address research questions that can help explain the impacts of climate change, disease, and other emerging threats. To understand these impacts, statistical methodology must be developed to address the nuance of the sampling design and provide inferences about the quantities of interest; this methodology must also be accessible and easily implemented by scientists. Recently, hierarchical latent variable modeling has emerged as a comprehensive framework for modeling a variety of ecological data types. In this dissertation, we discuss hierarchical modeling of multi-scale occupancy data and multi-species abundance data. Within the multi-scale occupancy framework, we propose new methodology to improve computational performance of existing modeling approaches, resulting in a 98% decrease in computation time. This methodology is implemented in an R package developed to encourage community uptake of our method. Additionally, we propose a new modeling framework capable of simultaneous clustering and ordination of ecological abundance data that allows for estimation of the number of clusters present in the latent ordination space. This modeling framework is also extended to accommodate hierarchical sampling designs. The proposed modeling framework is applied to two data sets and code to fit our model is provided. The software and statistical methodology proposed in this dissertation illustrate the flexibility of hierarchical latent variable modeling to accommodate a variety of data types.Item Pharmaceutical biomarkers to inform public and environmental health law and policy(Montana State University - Bozeman, College of Agriculture, 2020) Margetts, Miranda Lee; Chairperson, Graduate Committee: Robert K. D. Peterson and Deborah Keil (co-chair); Aparna Keshaviah, Cindy Hu, Victoria Troeger, Jordan Sykes, Nicholas Bishop, Tammy Jones-Lepp, Marisa Henry and Deborah E. Keil were co-authors of the article, 'Using wastewater-based epidemiology with local indicators of opioid and illicit drug use to overcome data gaps' submitted to the journal 'Journal of the American Medical Association' which is contained within this dissertation.; Terri Mavencamp, Jordan Sykes, Tammy Jones-Lepp, Nicholas Bishop, Victoria Troeger, Robert K. D. Peterson and Deborah E. Keil were co-authors of the article, 'The environmental impact of substance use in Montana's waterways: investigation of prescription, illicit, and recreational drug metabolite concentrations into receiving waters' which is contained within this dissertation.; Trent McCallson and Deborah E. Keil were co-authors of the article, 'Wastewater testing to support new environmental health compliance obligations in the healthcare industry' which is contained within this dissertation.The increasing awareness of the prevalence of prescription and illicit drug metabolites in wastewater is affecting changes to public and environmental health laws and policies. Drug takeback laws have been enacted to limit environmental pollution from drugs flushed into sewers; however, these laws only apply to legally prescribed drugs. Wastewater-based epidemiology, which relies on the measurement of drug concentrations in untreated wastewater, is also emerging as a complementary drug-use data tool to estimate drug consumption patterns by a community in near real-time. We sampled both the untreated influent and treated effluent at two locations in Montana over three months from April to June, 2019, to ascertain the concentrations of certain prescription and illicit drugs of abuse. The concentrations of drugs obtained from the untreated influent were used to inform a wastewater-based epidemiology study that compared drug-dose estimates from our wastewater samples against existing local drug-use sources (emergency medical services calls, drug seizures, and prescription dispense data). We also measured the treated effluent to determine the concentration at which drugs of abuse are persisting through the wastewater-treatment process and potentially affecting aquatic life exposed to those concentrations in receiving waters. We undertook a risk assessment whereby measured drug concentrations were assessed against corresponding ecotoxicology thresholds. Our results indicate that both codeine and morphine concentrations were above predicted no-effect concentrations. The overall results indicate that (1) wastewater-based epidemiology may be an effective tool to better describe substance abuse in communities and (2) drugs are persisting at levels above ecotoxicological thresholds from wastewater treatment plants into receiving waters. To our knowledge, these investigations are the first of their kind to have been conducted in Montana.Item Water quality response to water and nitrogen movement through a semi-arid dryland agroecosystem in Montana, USA(Montana State University - Bozeman, College of Agriculture, 2020) Sigler, William Adam; Chairperson, Graduate Committee: Stephanie A. Ewing; Stephanie A. Ewing, Clain A. Jones, Robert A. Payn, E.N. Jack Brookshire, Jane K. Klassen, Douglas Jackson-Smith and Gary S. Weissmann were co-authors of the article, 'Connections among soil, ground, and surface water chemistries characterize nitrogen loss from an agricultural landscape in the upper Missouri River Basin' in the journal 'Journal of hydrology' which is contained within this dissertation.; Stephanie A. Ewing, Clain A. Jones, Robert A. Payn, Perry Miller and Marco Maneta were co-authors of the article, 'Water and nitrate loss from dryland agricultural soils is controlled by management, soils, and weather' submitted to the journal 'Agricultural ecosystems & environment' which is contained within this dissertation.; Stephanie A. Ewing, Scott D. Wankel, Clain A. Jones, Sam Leuthold, E.N. Jack Brookshire and Robert A. Payn were co-authors of the article, 'Drivers of denitrification across a semiarid agroecosystem revealed by nitrate isotopic patterns' which is contained within this dissertation.Humans have increased reactive nitrogen (N) on the planet by an order of magnitude over the past 150 years. Most of this reactive N is used for fertilizer to feed a growing population, but loss of N from cultivated soils threatens agricultural and environmental sustainability. Nitrate accumulated in soil from fertilization or decomposition of soil organic N (SON) may be lost via leaching, which can reduce soil fertility and compromise water quality. Nitrate concentrations commonly exceed human drinking standards in groundwater resources around the globe. In the Judith River Watershed (JRW) in central Montana, nitrate has been detected above the standard since the 1960s. This dissertation contributes to a more holistic understanding of the fate and transport of N in the JRW. An interdisciplinary team engaged with farmers in a participatory research project, making observations in soils, groundwater, and streams to characterize water and N movement. At the landform scale, 5 to 9 cm yr -1 of the 38 cm yr -1 mean annual precipitation moves through soil to recharge groundwater and leaches 11 to 18 kg ha -1 yr -1 of nitrate-N from soil. These leaching rates are approximately 20-30% of fertilizer rates but likely reflect inmixing of nitrate from SON decomposition. Soil modeling analyses suggested that water and N losses were dominated by intense precipitation periods on wetter soils, such that more than half of simulated deep percolation and leaching occurred in two of 14 model years. Simulations further suggest that thinner soils (<25 cm fine-textured materials) experience water and nitrate loss rates five to 16 times higher than thicker soils (>100 cm). Soil sampling demonstrated that increased soil water during fallow periods facilitates conversion of SON to nitrate. Soils are then primed for water and N loss with subsequent precipitation, resulting in disproportionately high leaching rates during and following fallow periods. Isotopic evidence from fallow periods further suggests that nitrate is lost to the atmosphere via denitrification, a gas phase loss combining with leaching losses to compromise the goal of delivering N to crops. These findings suggest that reduction of fallow increases N use efficiency and reduces nitrate loss to groundwater.Item Towards a more-than-human geography of the Yellowstone River(Montana State University - Bozeman, College of Letters & Science, 2020) Bergmann, Nicolas Timothy; Chairperson, Graduate Committee: Jamie McEvoy; Jamie McEvoy, Elizabeth A. Shanahan, Eric D. Raile, Anne Marie Reinhold, Geoffrey C. Poole and Clemente Izurieta were co-authors of the article, 'Thinking through levees: how political agency extends beyond the human mind' in the journal 'Annals of the American Association of Geographers' which is contained within this thesis.This dissertation conceptualizes the Yellowstone River, flowing more than 670 miles from its headwaters in the mountains of northwestern Wyoming to its confluence with the Missouri River in western North Dakota, as a more-than-human assemblage. Specifically, this dissertation asks the following overarching research question: How does a more-than-human approach to understanding the Yellowstone River further geographical conceptualizations of human-environment relationships? In order to answer this question, this dissertation investigates the more-than-human aspects of both historical and contemporary environmental conflicts within Montana's portion of the Yellowstone River Basin. Chapter 2 examines the relationship between instream flow water law, Montana Fish and Game, and the Yellowstone River Basin. Drawing from both critical legal geography and political ecology, it furthers understandings of instream flow water law as relationally co-constituted through both human and nonhuman forces. Chapter 2 also traces the influence of Montana Fish and Game's more-than-anthropocentric ethical position on interpretations of the 1973 Montana Water Use Act. Chapter 3 uses a morethan- human approach to examine the relationship between myth and the Yellowstone River. Specifically, this chapter combines existing geographical understandings of myth with theories of assemblage and affect in order to historicize and denaturalize mythic belief in the Yellowstone as the longest undammed or free-flowing river remaining in the United States. Chapter 4 advances more-than-human understandings of political agency through a reframing of human thought as a co-constitutional assemblage of human and nonhuman elements. Relying on a comparative case study approach and qualitative interview data from two Montana communities located along the lower Yellowstone River, this chapter supports its theoretical claims through an embodied and affective analysis of the communities' divergent flood risk perceptions. Chapter 5 closes this dissertation with reflections on the value of using a more-than-human geographical approach.Item Reproductive ecology of hatchery-origin pallid sturgeon upstream of Fort Peck Reservoir, Montana(Montana State University - Bozeman, College of Letters & Science, 2020) Cox, Tanner Lewis; Chairperson, Graduate Committee: Christopher S. Guy; Christopher S. Guy and Molly A. H. Webb were co-authors of the article, 'First maturity, spawning periodicity, and follicular atresia of hatchery-origin pallid sturgeon in the Missouri River above Fort Peck Reservoir, Montana' submitted to the journal 'Journal of applied ichthyology' which is contained within this thesis.; Christopher S. Guy and Molly A. H. Webb were co-authors of the article, 'Reproductive ecology and behavior of hatchery-origin pallid sturgeon in the Missouri River above Fort Peck Reservoir, Montana' submitted to the journal 'Journal of applied ichthyology' which is contained within this thesis.Conservation propagation of pallid sturgeon above Fort Peck Reservoir has successfully recruited a new generation of spawning-capable pallid sturgeon to a location that would otherwise have fewer than 30 remaining. Successful recovery of pallid sturgeon will now rely on spawning in locations that provide adequate drift distance for larvae to recruit. Prior to this study, all reproductively-active female pallid sturgeon underwent ovarian follicular atresia. The reasons for and prevalence of ovarian follicular atresia were unclear, spawning periodicity of females remained undescribed, and remaining prepubescent fish indicated that age- and size-at-first maturity would vary more than currently described. Furthermore, spawning location, spawning-related interactions among conspecifics, and substrate composition at spawning locations remained undescribed. We used data on reproductive status and location to describe age- and size-at-first maturity, the prevalence of ovarian follicular atresia during first gametogenic cycles, spawning periodicity for female and male pallid sturgeon, where spawning occurs, if spawning locations are related to discharge, if substrate characteristics at the spawning locations were similar to other river reaches, and if female, male, and atretic female pallid sturgeon use the river similarly. Pallid sturgeon matured at older ages and larger sizes than described for other populations with females maturing at 18 years old and males at 15; however, prepubescent pallid sturgeon as old as 20 were documented. During the presumed-first gametogenic cycle, 62.5% of female pallid sturgeon underwent follicular atresia. Females had biennial reproductive cycles, and males had annual and biennial reproductive cycles. Reproductively-active male and female pallid sturgeon were found in similar locations, while locations of atretic female pallid sturgeon varied. The furthest upstream locations of pallid sturgeon including locations in the Marias River occurred during 2018 when discharge was at an unprecedented high. Spawning occurred in locations less than 131 km from the river-reservoir transition zone, which does not provide adequate drift-distance for larvae. Altering discharge and water temperature at Tiber Dam to mimic observed values in 2018 may increase use of the Marias River by pallid sturgeon during spawning, which would provide adequate drift distance to larvae.