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Item Trace Element Distribution in Soils of The Pembina Escarpment, North Dakota(North Dakota State University, 2010) Jyoti, VijayaAssociation of element concentrations for soils of northeastern North Dakota formed from different sources of parent materials were determined based on geochemical data. These soils overlie the Cretaceous Pierre Formation and parent materials consist of shale rich glacial till, residual shale, and colluvial materials. Surface and core sampling locations included a cropped field, Conservation Reserve Program land, and grassland fields in a North Dakota State Wildlife Management Area. Samples were analyzed for cadmium and other trace elements using a nitric acid digestion followed by optical emission spectroscopy. Results of a preliminary study in cropped and CRP fields showed elevated concentrations of cadmium. Later comprehensive field work in a Wildlife Management Area was carried out to examine the landscape scale variation for a suite of elements. Morphologic and laboratory analysis of soil cores indicate high clay content with mixed clay mineralogy, indicative of the influence of shale residuum on the parent materials of the escarpment soils. Chemical properties of the escarpment soils revealed high levels of organic matter (2.62-13.30 %), ultra acidic to slightly alkaline pH range, and low electrical conductivity for the soils. Average cadmium concentration of 0.28 mg/kg was reported for the samples from eight cores while 16.4 mg/kg cadmium was found in the CRP field sample. Correlations of different analytes with cadmium showed significance with shale and argillic horizons. Principal Component Analysis revealed that elevated trace element concentrations for the soils in northeastern North Dakota are linked to a variety of factors including organic matter content, clay mineralogy, pH, elevation, and electrical conductivity. Results of this study suggest that lateral as well as vertical water movement of water could be an important factor leading to transport and elevated trace metal zones in these soils.Item OSL Dating of High-Elevation Alluvial Sediments: McMurdo Dry Valleys, Antarctica(North Dakota State University, 2015) Ramsey, Meridith AnnHigh-elevation alluvial fans in the McMurdo Dry Valleys are a record of short-term, occasional melting events along the margins of the East Antarctic Ice Sheet. Sediment samples were dated from five fans using Optically Stimulated Luminescence (OSL) dating. OSL dates the time since quartz grains were last exposed to sunlight; all sample preparation takes place in a dark room. Thirteen samples were dated for this thesis, the ages were stratigraphically consistent and ranged from 1.1 ka to 105.9 ka. Clusters of fan activity occurred between 1.1 and 3.1 ka and 8.1 and 11.1 ka. The melting events appear to be linked to insolation, with periods of fan activity occurring usually at times of increased mean annual insolation. The alluvial fans show promise as a possible archive for climate proxies in this region of Antarctica.Item Wetland restoration in the North Dakota Prairie Pothole Region: a macroinvertebrate community perspective(North Dakota State University, 2024) Sauskojus, WhitneyThis study assessed the long-term recovery of aquatic macroinvertebrate communities to wetland restoration. Previous research has suggested that even after a decade post restoration, macroinvertebrate communities may not fully resemble those of undisturbed reference sites, and how effective wetland restorations are in recovering macroinvertebrates is unclear. To assess macroinvertebrate recovery to restoration over long-time frames, thirteen restored and five reference wetlands were sampled in the North Dakota Prairie Pothole Region during July and August of 2019. Restored wetlands ranged from 20 to 32 years post-restoration, within restoration dates spanning between 1987-1999. Differences were examined between reference and restored sites, along with differences between four age categories: 20-26 years (n = 4), 29 years (n = 4), 31-32 years (n = 5) and reference sites (n = 5). No significant differences were found in aquatic macroinvertebrate richness and diversity between reference and restored wetlands, or among restoration age groups. Community composition was also similar among all restoration age groups, with no apparent influence from measured chemical and physical water variables and soil organic matter. These results suggest, within the Prairie Pothole Region, that restored wetlands contain diverse macroinvertebrate communities that resemble undisturbed reference sites after 20 to 32 years post-restoration.Item Antipredator Behavior and Morphology in Isolated Cyprinodont Fishes(North Dakota State University, 2018) Snider, Madison R.For desert fishes in the American Southwest, predation by invasive species has triggered massive population declines for decades, leaving researchers speculating on the underlying cause. It has been shown that Post-Pleistocene isolation of desert fishes in small habitats with limited predation pressure has led to loss of antipredator traits. Determining the status of antipredator behavioral and morphological traits could identify the most vulnerable desert fishes. In aquatic ecosystems, detection and response to chemical alarm cues derived from epithelial tissue increases the probability of predation survival. In chapter two, I evaluate alarm cue responses of two desert cyprinodontids: endangered Pahrump poolfish and Amargosa pupfish. In chapter three, I assess the prevalence and densities of epithelial club cells, the source of chemical alarm cues, for several desert fishes: Pahrump poolfish, Amargosa pupfish, White Sands pupfish, White River Springfish, and Hot Creek Valley tui chub.Item Body Shape Divergence Among Wild and Experimental Populations of White Sands Pupfish (Cyprinodon Tularosa)(North Dakota State University, 2011) Kowalski, Brandon MichaelReports of contemporary evolution have become ubiquitous, but replicated studies of phenotypic divergence for wild populations are exceptionally rare. In 2001, a series of experimental populations were established to replicate a historic translocation event that led to a case of contemporary body shape evolution in the White Sands pupfish. Using landmark-based geometric morphometric techniques I examined phenotypic variation for seven of these populations, and two wild populations over a 5 year period (5-10 generations) in the field. Significant body shape divergence was observed, but divergence patterns were not parallel, suggesting that the ponds were ecologically dissimilar. Considerable body shape variation found among populations suggests that the observed divergence maybe governed by temporal environmental variance. In this study, body shape variation was correlated with population density. These data suggest that habitat intrinsic factors or unmeasured habitat features may have strong affects on body shape, warranting continuous monitoring of recently translocated fishes.Item Ex Situ Analyses of Non-Native Species Impacts on Imperiled Desert Fishes(North Dakota State University, 2019) Paulson, BrandonThis thesis focuses on interactions between two invasive species, the western mosquitofish (Gambusia affinis) and the red swamp crayfish (Procambarus clarkii), and two desert fishes, the Amargosa pupfish (Cyprinodon nevadensis) and the endangered Pahrump poolfish (Empetrichthys latos latos). Chapter one is a literature review on the impacts of invasive species on various desert fishes. Chapter Two reports the results of multiple mesocosm experiments that show poolfish are unlikely to persist in the presence of mosquitofish. Chapter Three reports the results of a mesocosm experiment that tested the combined impacts of crayfish and mosquitofish on poolfish populations. Chapter Three mimics a historic case study in Nevada, where the Lake Harriett poolfish population crashed following the introduction of crayfish and mosquitofish. Chapter Four reports results of a mesocosm experiment that revealed density dependent effects of invasive crayfish on pupfish populations, with pupfish populations negatively affected when crayfish were at high densities.Item Late Pleistocene Mountain Glacier Equilibrium Line Altitudes and Paleoclimate Reconstruction in the Great Basin(North Dakota State University, 2022) Walter, LarkinThis thesis presents new reconstructions of paleoglacier surfaces and Equilibrium Line Altitudes in nine mountain ranges in the northeastern Great Basin during the Last Glacial Maximum. Improved methods for paleoglacier and ELA reconstructions were applied in this thesis, using a computationally derived toolset presented by Pellitero et al. (2015, 2016). Additionally, the first computationally derived volume estimates for alpine paleoglaciers in Lake Bonneville are presented. These reconstructions, in addition to 10Be cosmogenic exposure ages taken from the ICE-D website, were used together to further limit the magnitude and climate of the Last Glacial Maximum. Equilibrium Line Altitudes provide a vital link between the mass balance of a glacier and its relationship with climate. Reconstructing these relationships in the Great Basin showed the regional maxima did not coincide with the Lake Bonneville highs stand and the melting of glaciers following the LGM was not the driving factor in the Lake overflow.Item Use of Biopolymer Entrapped Sulfate Reducing Bacteria and Metal Nanoparticles for Effective Aqueous Sulfate Removal(North Dakota State University, 2013) Cisse, SeydouSulfate reducing bacteria (SRB) isolated from activated sludge were used to investigate sulfate removal from aqueous solution using calcium alginate entrapped SRB in batch studies with ethanol and lactose as the carbon sources. The interferences of pH, temperature, Al3+, Cu2+, and Zn2+ on sulfate removal were also investigated. Further, sulfate removal experiments were conducted with co-entrapped SRB and nanoscale zero-valent iron (NZVI) and separately entrapped SRB and NZVI. Results indicate that EntSRB can effectively remove sulfate from aqueous solution. 88-95% sulfate removal was achieved. Both ethanol and lactose worked well as carbon sources for entrapped bacteria. Interference studies indicated low sulfate removal in the presence of 25-50 mg/L of aluminum and zinc. Low pH (pH≤ 4) and low temperature (5°C) decreased sulfate reduction. NZVI appeared to have negative effects on SRB. Loading of 0.05 and 0.1 g of NZVI led to lower SO42- removal as compared to experiments without NZVI.Item Mycorrhizas and the Context Dependency of Mutualism: Effects of Soil Phosphorus Availability and Community Composition of Arbuscular Mycorrhizal Fungi on Plant Performance and Symbiosis With the Grassland Forb Gaillardia aristata Across Its Northern Range(North Dakota State University, 2021) Long, AlisonArbuscular mycorrhizal fungi (AMF) colonize roots and provide phosphorus as well as other benefits to hosts in exchange for photosynthate. I explored how the symbiosis between AMF and the native prairie forb Gaillardia aristata differed regionally among sites that varied in soil phosphorus availability (SPA). In the field, plant biomass and shoot phosphorus concentration were correlated with SPA and hyphal length. AMF community composition in roots correlated with distance between sites, SPA, temperature, and precipitation. To test the hypothesis that AMF from sites varying in SPA would differ in effectiveness at provisioning phosphorus to their host, I grew G. aristata in the greenhouse with soil inoculum from sites low and high in SPA and fertilized with or without phosphorus. Gaillardia aristata benefited equally from both inocula and phosphorus fertilization, while root AMF communities differed between inocula but not with fertilization. AMF from varying SPA appear to be equally effective mutualists.Item Evaluation of a Nitrate-Assimilating Bacterium for Potential Use in Nitrate Bioremediation(North Dakota State University, 2013) Lies, Deidra AngelineIncreasing levels of nitrate (NO3-N) in water resources have brought about the need to find ever more versatile forms of NO3-N removal from contaminated water. The ability of several microorganisms to transform NO3-N has been embraced as an economical form of bioremediation. Free cell and immobilized forms of Methylobacterium fujisawaense ATCC® No. 35065 (M. fujisawaense) were used in this study for NO3-N removal in batch settings. NO3-N removal results were as high as 100% for freely suspended cells after 96 hours and 95% for immobilized cells also after 96 hours. Statistical analyses found no significant difference in overall NO3-N removal rates between free cell and immobilized systems. These findings suggest that the organism is capable of up to full assimilation of 10 mg/L NO3-N in certain settings. The findings also suggest that the NO3-N assimilating ability of M. fujisawaense of 10 mg/L NO3-N is not greatly altered by immobilization.