MSU Student Research Celebration
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/405
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Item Can We Help Worms Help Us?(Montana State Univeristy, 2017-04) Wallisch Simon, KelseyScientists have been studying earthworm’s effects on soil chemistry, specifically how they can affect the mobility and bioavailability of heavy metals in a contaminated soil. Studies have shown that their effects of this specific piece of soil chemistry vary greatly with soil properties such soil texture, pH and actual earthworm species. Very little data exists with respect how Montana worms influence Montana soils. This study looks at Lumbricus rubellus across two different contaminated soils from Montana: Neihart mine tailings outside of Helena, Montana and Silver Bow/Butte Parrot Mine tailings. Two soil amendments were used to assist the earthworms’ survival and productivity. Lime is used in graduated increments to define the worms’ pH tolerance. Organic matter is often sparse across mine tailings and is added as an additional treatment for soil physical, chemical and biological processes. Water and weak acid (ammonium acetate) were used to extract the metal-contaminated soils; these extracts were used to quantify the lead (Pb) mobility. This study is designed to mimic a low-cost, long-term approach to vermi-remediation of lead-contaminated soil to provide a model across mine tailings and the Northern Rocky Mountains.Item Tests of Various Compost Inoculum on Rate of Decomposition and Food Production(Montana State Univeristy, 2017-04) Rychener, PaulAs universities work to reduce their carbon footprints, campuses are composting, rather than landfilling, food waste. Unfortunately, few studies of composting outcomes exist, and there are even fewer studies analyzing compost methods. This study analyzed 3 methods for treating food waste at various concentrations. Bokashi is a compost inoculum, which uses a wheat bran-type substrate hosting “effective microorganisms”. Here we report the results from a three-phase compost study of pre-consumer food waste. Five food waste treatments included a no inoculum control, and single or 3-layer treatment, of Bokashi or soil. For Phase 1, we fermented the food waste in five-gallon buckets, measuring the headspace carbon dioxide (CO2). The CO2 to soil ratios declined from approximately 300 to approximately 100 over 4 weeks showing little variation between treatments. For Phase 2, compost decomposition completed in the field, measured by soil respiration rates, showed a large initial spike (above 150 micromoles of CO2/meter2/second), then declined over a 6-week period. For Phase 3, the compost was dried and ground, then used as a nutrient amendment to grow lettuce. Biomass increase occurred for all amended treatments, surprisingly, the largest increase (150%) was found for the food-only compost treatment. Our results suggest Bokashi and soil amendments provide little to no additional benefit compared to food-only compost. Future work should assess emissions produced through these types of composting efforts, to more quantitatively evaluate the benefits of composted food waste versus potentially avoided greenhouse gas emissions (e.g., methane and nitrous oxide) associated with landfilled food waste.Item Understanding the Effects of Herbicide Application on Hoary Alyssum (Berteroa incana L.) Seed Biology(Montana State Univeristy, 2017-04) Menalled, Uriel D.Hoary alyssum (Berteroa incana L.), a non-native plant, invasive plant is difficult to manage because of its long flowering period, during which it simultaneously flowers and produces seeds. Consequently, improper herbicide application may kill flowers but not seeds. Since hoary alyssum reproduces exclusively by seed, we examined how different herbicides affect its seed production, viability, and germination. Invasive plant managers treated hoary alyssum with various herbicides on six rangeland sites across southwestern Montana. Managers recorded flower and seed pod development of hoary alyssum. We randomly collected 20-30 hoary alyssum plants from treated and non-treated areas at each site about four weeks post-treatment. We determined seed production and analyzed seed viability using tetrazolium tests. Seed germination was examined for two sites under current and predicted temperatures. At four of six sites, herbicide treatments reduced hoary alyssum seed production by 49-98% compared to non-treated areas. Herbicide treatments significantly reduced seed production at sites sprayed at early developmental stages, or when on average, <50% of a flowering stem had seed pods. All herbicide treatments, except for chlorsulfuron + 2,4-D, significantly decreased seed viability. Seed viability in non-treated areas ranged from 36-73%. Seeds from treated areas, except those treated with chlorsulfuron + 2,4-D, exhibited 0-21% viability. While we are still analyzing germination, we predict that germination will increase with temperature, but the relationship may vary across herbicides. Our research suggests that the application of some herbicides early during hoary alyssum flower and seed pod development can effectively reduce seed production and viability.Item Entomology Collections Curation of Hymenoptera at Smithsonian Museum of Natural History(Montana State Univeristy, 2017-04) Maxcer, MilesWith the over 35 million specimens housed at the Smithsonian Department of Entomology’s National Insect Collection, there comes an extensive challenge in keeping the collection organized, updated, and recorded in online databases. Additionally, the Smithsonian is tasked with engaging the public. This project will include the learning and application of taxonomical and curatorial techniques, in addition to the production of entomological film media for the Smithsonian Institution and its partner, the U.S. Department of Agriculture’s Agricultural Research Service. Because the Smithsonian is a major repository for insect specimens from important research worldwide, preparation for the project was necessary to ensure that the requisite knowledge and techniques would be used to preserve the integrity of the collection and make the work efficient and accurate. The presentation will include information and media relating to the internship experience at the Smithsonian Department of Entomology. My specific focus will be on the curation of parasitic Hymenoptera in the superfamily of Chalicidoidae wasps. The poster presentation will cover the concepts learned, including critical skills in museum curation (handling fragile museum-quality specimens, labeling, databasing, and sorting specimens), systematics, taxonomy, basic research, and media creation.Item Does greater saturation lead to faster soil carbon accumulation in a restored wetland?(Montana State Univeristy, 2017-04) Kirby, KoryWetlands provide many ecosystem services. In Bozeman, MT, Story Mill wetland site is being restored and converted into a public park by The Trust for Public Land and The City of Bozeman because of these services. Carbon sequestration via restoration of wetland soils is receiving a lot of interest to mitigate carbon dioxide increases. An initial step in restoring these ecosystem services was the creation of the Bozeman Creek Backwater Slough (BCBS), a side channel constructed by excavating nearly ~6200 yds3 of soil to improve surface water quality by enabling Bozeman Creek to spread over a much greater area during flood events. This excavation has established a time zero for measuring baseline rates of carbon accumulation. My previous research has already answered how much soil carbon was lost due to excavation: I estimated 26%. This research looks to answer if carbon is accumulating at Story Mill, and, if so, at what rate? My hypothesis is that organic matter accumulation rates will be greatest in the most reduced/anaerobic location and organic matter accumulation rates will be lowest in the most oxidized/aerobic location along my sampling transects. I will characterize twelve soil profiles, nine in the BCBS, three outside the slough in which I can compare these results to last year results establishing if carbon is accumulating, and if so how much has accumulated over the course of one year. Though my work will only help quantify how much soil carbon can be sequestered in one part of Montana under these conditions, hopefully I can contribute to the statewide portfolio of Montana solutions to climate change.Item Course organic matter distribution and soil moisture retention capacity(Montana State Univeristy, 2017-04) Ippolito, Laura; Rychener, PaulOrganic matter (OM) is a critical component of the soil in agriculture in arid or semi-arid regions in particular because of its ability to retain water in the soil. This raises the question, how does spatial distribution of OM in soil play a role in efficiency of soil moisture retention. The purpose of this experiment was to recreate three treatments, mimicking different ways OM is incorporated into the soil in an agricultural setting, along with a control which has no additional OM. To do this, the first treatment had OM fully submerged beneath the soil surface to show an increase of OM content compared to the control. The second treatment had 80% OM buried and 20% sticking out, mimicking a tilled agricultural setting. The final treatment had OM 80% buried with 20% stubble sticking out with intact root systems, to mimic summer fallow. To measure water retention, each pot was ¼ submerged under water overnight to fully saturate the soil. After saturation, the pots were weighed and then placed in a drying oven. The pots were periodically re-weighed at time 0, 0.5, 1, 2, 4, 8, 12, 24, 36, 48, 60, 72, 96, 120, 144, 168, 192, 216, 336 hours. Preliminary results show the fallow treatment had the most loss in water, followed by the unamended soil control, tilled soil treatment, and the most water retention was in the soil with an increased OM content. This study suggests that additionally completely buried OM has the highest water retention.Item Analysis of Long Term Photosynthetically Active Radiation Data from McMurdo Dry Valley Lakes to Identify Turbidity Stratification Patterns(Montana State University, 2015-04) Pedersen, StephenThe current study focused on four perennially ice covered, meromictic, fresh water lakes in the Taylor Valley of the McMurdo Dry Valley region: West and East Lobe Bonney, Fryxell, and Hoare. Data from these lakes have been collected annually for more than 25 years, and are cataloged in the McMurdo Dry Valley Long Term Ecological Research database. The objectives of the current study were to determine whether turbidity stratification patterns could be identified within the four McMurdo Dry Valley Lakes, to look for seasonal and annual changes in those stratification patterns, and to correlate environmental data to identify potential causes of the turbidity. To identify patterns in turbidity, extinction coefficient depth profiles were calculated using photosynthetically active radiation data collected annually during the past 29 years. Averaging the profiles revealed distinct stratification of turbidity layers that were shown to be relatively stable across all recorded years. To examine potential causes of turbidity revealed by the extinction coefficient data, chlorophyll-a profiles were compiled for the same years, and compared to those of the extinction coefficients. Within the photic zones of Lake Hoare and East and West Lobe Bonney, chlorophyll-a was significantly correlated with turbidity. A linear plot of extinction coefficients against time revealed that later season average turbidity is much higher than that of early season turbidity, and that turbidity increases with depth in the photic zones of all lakes. Future research focusing on stream flow data could help identify the causes of the increase in late season turbidity observed in this study, and analysis of environmental data other than chlorophyll could help to determine what other phenomena control turbidity gradients in Lakes Fryxell and Hoare.Item Autotrophic Carbon Fixation in Crenarchaeota from Yellowstone National Park(2013-03) Whitmore, Laura M.; Inskeep, WilliamAutotrophy in the archaea has recently been described as an important and under-studied source of global carbon fixation. Several archaeal species are found in ferric oxyhydroxide mats from acidic geothermal springs in Yellowstone National Park. The springs are an exceptional natural laboratory for studying microorganisms in constrained systems. However, primary productivity had not been demonstrated in these systems. The goal of this study was to confirm autotrophic growth in pure Metallosphaera yellowstonensis, a dominant community member in Fe(III)-oxide mats, and relate this to in situ microbial communities. M. yellowstonensis was grown chemolithoautotrophically with pyrite as the electron donor, oxygen as the electron acceptor, and 13CO2 as the sole carbon source. At post log-phase, biomass was analyzed using isotope-ratio mass spectrometry (IRMS) at Pacific Northwest National Laboratory. The results demonstrated that M. yellowstonensis is capable of inorganic carbon fixation. Furthermore, the isotope fractionation value was consistent with an operating 3-hydroxypropionate/4-hydroxybutyrate cycle, characteristic in other Sulfolobales. Ex situ Fe(III)-oxide mat samples were incubated with pyrite, oxygen, and 13CO2, and analyzed by IRMS. The data show that under limited organic carbon, these communities are capable of CO2 fixation. Currently, transcriptomics and q-rt-PCR are being utilized to confirm the expression of key autotrophy genes.Item Alkaliphilic Microalgae for Biofuel Production: Scaling-up to 50 Liter Bag Bioreactors(2013-03) Schmidt, Matthew; Macur, RichThe use of microalgae for the production of biofuels is in the spotlight due to a reputationfor high photosynthetic efficiency, rapid growth rates, high oil productivity and potential for growth in saline or brackish waters in landscapes not suited for crop production. Research and engineering efforts are now focused on overcoming a variety of hurdles to reduce production costs and attain economic viability. Extremophilic algae have unique attributes that can potentially be used to overcome some of the problems associated with biofuel production, including resistance to competitive organisms. The objective of this research was to characterize the growth three extremophilic algal strains in 250 mL shaker flasks, and then characterize growth of the most promising strain in a larger scale (100 L) bag reactor. Of the three algae examined, strain PGV-8 showed the most promise for scaling-up based on growth rate (cell counts) and oil production as measured by Nile Red fluorescent staining. Strain PGV-8 demonstrated a maximum doubling time of about 1.5 d and produced significant quantities of oil in a 100 L bag reactor system, revealing that it has potential for use in larger scale systems.Item Bystander exposure to ultra-low-volume insecticide applications used for adult mosquito management(2013-03) Preftakes, Collin J.; Peterson, RobertA popular and effective management option for adult mosquitoes is the use of insecticides applied by ultra-low-volume (ULV) equipment. However, there is a paucity of data on human dermal exposure to insecticides applied by this method. The objective of the current study was to estimate dermal exposures to the insecticide active ingredient permethrin using water- (Aqua-Reslin®) and oil-based (Permanone® 30-30) formulations with passive dosimetry. No significant differences in deposition of permethrin were observed between years, distance from the spray source, front or back of the body, or the placement of the patches on the body. However, exposure to Aqua-Reslin was significantly greater than Permanone 30-30 and average concentrations deposited on the body were 4.2 and 2.1 ng/cm2, respectively. The greater deposition of Aqua-Reslin is most likely due to the higher density of the water-based formulation which causes it to settle out faster than the lighter oil-based formulation of Permanone 30-30. The estimated average absorbed dermal exposure for permethrin from Aqua-Reslin and Permanone 30-30 was 0.00009 and 0.00005 mg/kg body weight, respectively. We also found that ground deposition of ULV insecticides can be used as a surrogate for estimating dermal exposure. The estimated exposures support the findings of previous risk assessments that exposure to ULV applications used for mosquito management are below regulatory levels of concern.