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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 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 Water stress in Montana cropping systems: effects of cultivar, management, and environment on crop production in dryland systems(Montana State University - Bozeman, College of Agriculture, 2016) Bestwick, Michael Linn; Chairperson, Graduate Committee: Richard E. Engel; Chengci Chen (co-chair)Crop productivity--defined as yield, protein, and economic returns--hinge on crop water use. Crop water use is a function of genetic, environment, and management factors. This thesis addresses how these factors interact with crop water use and productivity in Montana. In chapter 2, a two-year (2014-2015) study compared winter wheat yield and protein following fallow and three intensive sequences on deep and shallow soils. Water extraction was measured on deep soils, and kriged soil depth estimates served as a surrogate for stored soil moisture on shallow soils. On deep soils, yields ranged from 72-84% of fallow-wheat from 20.5 mm less water extracted below 45 cm, while protein was ~0.63% greater in intensified sequences. On shallow soils, sequence did not affect yield or protein. Yields increased with soil depth while protein decreased in 2014, but no trends were observed in 2015 due to 47 mm greater precipitation from joint to heading. Intensive sequences diminish wheat productivity on deep soils, whereas soil depth and precipitation timing control productivity on shallow soils. In chapter 3, state-wide cultivar testing, soils, and climate data was used to quantify four general drought patterns in winter wheat and five in pea. Cultivar had little impact on yield compared to drought pattern with winter wheat yields ranging from 4421 kg ha -1 to 2539 kg ha -1 and pea yields ranging from 2877 kg ha -1 to 975 kg ha -1. Yields negatively correlated with drought intensity at heading in wheat (r 2=-0.79) and flowering in pea (r 2=-0.76). Quantifying drought patterns provides a physical interpretation to improve management and breeding efforts. In chapter 4, yield-evapotranspiration (ET) functions were derived for spring wheat, pea, and chickpea from a three-year (2002-2004) seeding date trial. Yield-ET functions were coupled with ten-year (2005-2015) climate records to predict yields at four staggered seeding dates. Yield predictions were converted to marginal revenues based on high, medium, and low markets and fixed production costs. Across seeding dates and markets, simulated returns were highest for chickpea (~601 $ ha -1) followed by wheat (372 $ ha -1) and pea (202 $ ha -1). This indicates chickpea should be seeded before wheat and pea.Item Factors influecing the abundance of microorganisms in icy environments(Montana State University - Bozeman, College of Agriculture, 2016) Santibanez-Avila, Pamela Alejandra; Chairperson, Graduate Committee: John C. Priscu; Joseph R. McConnell and John C. Priscu were co-authors of the article, 'A flow cytometric method to measure prokaryotic records in ice cores: an example from the Wais Divide drilling site' submitted to the journal 'Journal of glaciology: instruments and methods' which is contained within this dissertation.; Mark Greenwood, Joseph R. McConnell and John C. Priscu were co-authors of the article, 'Prokaryotic concentration changes between the last glacial maximum and the early Holocene from the Wais Divide ice core' submitted to the journal 'Quaternary science reviews' which is contained within this dissertation.; Alexander B. Michaud, Trista J. Vick-Majors, Juliana D'Andrilli, Amy Chiuchiolo and John Priscu were co-authors of the article, 'Bacterial response to progressive freezing in perennially and seasonally ice-covered lakes' submitted to the journal 'Journal of geophysical research (JGR) biogeosciences' which is contained within this dissertation.Microbial life can easily live without us; we, however, cannot survive without the global catalysis and environmental transformations it provides' (Falkowski et al., 2008). Despite of the key role of microbes on Earth, microbial community characteristics are not explicitly part of climate models because our understanding of their responses to long-term environmental and climatic processes is limited. In this study, I developed a Flow Cytometric protocol to access a long-term record of non-photosynthetic prokaryotic cell concentration archived in the West Antarctic Ice-Sheet (WAIS; chapter 2). The WD ice core was retrieved between 2009 and 2011 to a depth of 3,405 m, extending back to 68,000 before 1950. Once a 17,400 year-record of prokaryotic cell concentration was acquired, I investigated its temporal variability and patterns, determined the potential sources of prokaryotic cells between the Last Glacial Maximum and the early Holocene, and assessed the environmental factors that might have the largest influence on the prokaryotic response (chapter 3). The observed patterns in the prokaryotic record are linked to large-scale controls of the Southern Ocean and West Antarctica Ice-Sheet. The main research findings presented here about the first prokaryotic record are: (i) airborne prokaryotic cell concentration does respond to long-term climatic and environmental processes, (ii) the processes of deglaciation, sea level rise and sea-ice fluctuation were key; the abundance of prokaryotic cells covariate with ssNa and black carbon, and (iii) the prokaryotic cell record variate on millennial time scale with cycles of 1,490-years. In addition, I studied 'congelation ice' (i.e., ice forms as liquid water freezes) from ice-covered lakes to understand prokaryotic cell segregation between liquid and solid phases during the physical freezing process. Five mesocosm experiments were designed to understand prokaryotic responses to the progressive freezing in concert with field observations from ice-covered lakes from Barrow, Alaska. As a result of this last study (chapter 4), I concluded that prokaryotic cells are preferentially incorporated in the ice with segregation coefficients (K eff) between 0.8 - 4.4, which are higher than for major ions. Prokaryotic cells avoid rejection more effectively from the ice matrix.Item Uranium Isotopes and Dissolved Organic Carbon in Loess Permafrost: Modeling the Age of Ancient Ice(2015-03) Ewing, Stephanie A.; Paces, J. B.; O'Donnell, Jonathan A.; Jorgenson, M. T.; Kanevskiy, Mikhail Z.; Aiken, George R.; Shur, Y.; Harden, J. W.; Striegl, R.The residence time of ice in permafrost is an indicator of past climate history, and of the resilience and vulnerability of high-latitude ecosystems to global change. Development of geochemical indicators of ground-ice residence times in permafrost will advance understanding of the circumstances and evidence of permafrost formation, preservation, and thaw in response to climate warming and other disturbance. We used uranium isotopes to evaluate the residence time of segregated ground ice from ice-rich loess permafrost cores in central Alaska. Activity ratios of 234U vs. 238U (234U/238U) in water from thawed core sections ranged between 1.163 and 1.904 due to contact of ice and associated liquid water with mineral surfaces over time. Measured (234U/238U) values in ground ice showed an overall increase with depth in a series of five neighboring cores up to 21 m deep. This is consistent with increasing residence time of ice with depth as a result of accumulation of loess over time, as well as characteristic ice morphologies, high segregated ice content, and wedge ice, all of which support an interpretation of syngenetic permafrost formation associated with loess deposition. At the same time, stratigraphic evidence indicates some past sediment redistribution and possibly shallow thaw among cores, with local mixing of aged thaw waters. Using measures of surface area and a leaching experiment to determine U distribution, a geometric model of (234U/238U) evolution suggests mean ages of up to ∼200 ky BP in the deepest core, with estimated uncertainties of up to an order of magnitude. Evidence of secondary coatings on loess grains with elevated (234U/238U) values and U concentrations suggests that refinement of the geometric model to account for weathering processes is needed to reduce uncertainty. We suggest that in this area of deep ice-rich loess permafrost, ice bodies have been preserved from the last glacial period (10–100 ky BP), despite subsequent fluctuations in climate, fire disturbance and vegetation. Radiocarbon (14C) analysis of dissolved organic carbon (DOC) in thaw waters supports ages greater than ∼40 ky BP below 10 m. DOC concentrations in thaw waters increased with depth to maxima of >1000 ppm, despite little change in ice content or cryostructures. These relations suggest time-dependent production of old DOC that will be released upon permafrost thaw at a rate that is mediated by sediment transport, among other factors.Item Radiocesium in Montana soils and applications for soil erosion measurement(Montana State University - Bozeman, College of Agriculture, 1984) Arnalds, Olafur Gestur; Chairperson, Graduate Committee: Gerald A. NielsenRadiocesium levels in soils were measured at eleven sites throughout Montana. Cesium was mostly confined to the top of the soil profile. Both lateral and vertical displacement of cesium was attributed to mechanical movement of soil particles. The areal activity of cesium was strongly correlated to annual precipitation (R^2 = 0.92). An equation is given to predict cesium activity from annual rainfall. Methods of calculating soil erosion and deposition are discussed and performed for a wind erosion study site in Pondera County and a small watershed in Teton County. The results indicate that deposition at the wind erosion study site can be quantified. Soil deposition of 70 to 1290 m^3 ha^-1 was measured on the leeward sides of a fence and tree windbreaks while an average of 450 m^3 was lost from the windward sides. An average of 740 m^3 ha^-1 was lost since 1962 from an adjacent wind eroded field. This amounts to 34.8 Mg ha^-1 yr^-1. Soil loss since about 1962 ranged from 300 to 820 m^3 ha^-1 within the upper areas of the watershed studied. A pond at the outlet of the watershed and deposition areas at the toeslope accounted for a relatively small fraction of the soil loss within the watershed. Most of the losses are likely to be from wind erosion. Length of slopes or position within the field were more related to erosion than was steepness of slopes, Estimates of erosion rates based on 137Cs ranged from 16.5 Mg ha^-1 yr^-1 at the summit of the watershed to 45.1 Mg ha^-1 yr^-1 at the midslope. Predictions by conventional methods (wind erosion equation and the Universal Soil Loss Equation) agreed rather closely with the estimates from 137Cs.Item The potential for dryland alfalfa on minesoils in southeastern Montana(Montana State University - Bozeman, College of Agriculture, 1985) Postle, Robert CairnsItem Indirect effects of herbicides on an agroecological trophic system(Montana State University - Bozeman, College of Agriculture, 2001) Taylor, Rebecca Lynn