Theses and Dissertations at Montana State University (MSU)
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Item Interactive effects between lime, organic matter, and bacteria in the establishment of Leymus cinereus in mine tailings(Montana State University - Bozeman, College of Agriculture, 2015) Sanchez Espinoza, Deicy Noemi; Chairperson, Graduate Committee: Anthony HartshornThe landscape legacy of historical metal-mining activity can persist for decades. The most frequent strategies used for the remediation of contaminated soils include: the use of synthetic membranes to isolate contaminants (>$0.5 million/acre), direct revegetation (less expensive but difficult to sustain), or lime amendments ($5000/acre). Looking for more cost-effective bioremediation approaches, we performed a set of greenhouse studies to determine what combinations of soil amendments would lead to the best vegetative response, and potentially associated reductions in soil arsenic (As) levels, in "slickens" collected from the Lampert Ranch along the upper Clark Fork near Warm Springs, MT. In our first greenhouse experiment, we planted Leymus cinereus (basin wildrye) and compared (after 12 weeks) plant growth and foliar metal concentrations across treatments. Amendments included single or factorial additions of 5% lime, organic matter (+OM), and an arsenic-oxidizing (+oxbact) strain of Agrobacterium tumefaciens (Agtu). Surprisingly, the OM+oxbact treatment revealed among the best plant growth and arsenic uptake response. We then performed a second greenhouse experiment with two levels of OM (1.5% and 5%) and an additional treatment: a mutant (reducing strain) of Agtu. Basin wildrye grown in soils amended with 5% OM generally did better than those grown in soils amended with 1.5% OM. At the same time, foliar As uptake (biomass multiplied by As concentration) was unexpectedly high (0.020 mg pot-1) for plants grown in soils amended with 5% OM + oxbact, 3 times greater than foliar arsenic uptake in plants grown in soils amended with 5% OM+ lime and 4 times greater than foliar uptake by plants grown in soils amended with 5% OM and the reducing strain of Agtu. These results suggest the combination of OM and Agtu oxbact strain could provide a potentially cost- effective approach to remediating As-contaminated soils. Finally, our study results imply that soil restoration approaches could be improved through a greater consideration of microbial communities supported by these re-establishing vegetation communities, which could lead to more sustainable ecosystem successional trajectories.Item Development of wildlife habitat on mined lands(Montana State University - Bozeman, College of Agriculture, 1982) Carlson, Robert Steven; Chairperson, Graduate Committee: Frank Munshower.Item Effect of two dolomitic industrial by-products on pH control, leachate chemistry and plant response in acidic-metalliferous mine waste(Montana State University - Bozeman, College of Agriculture, 1997) Kelly, Laureen SusanItem Abandoned coal waste reclamation in Montana(Montana State University - Bozeman, College of Agriculture, 1987) Gitt, M. J.Item Factors affecting the native species invasion of a reclaimed subalpine minesite near Grande Cache, Alberta(Montana State University - Bozeman, College of Agriculture, 1987) Van Zalingen, Sylvia FrancesItem Effect of slope gradient and plant cover on soil loss on reconstructed high altitude slopes(Montana State University - Bozeman, College of Agriculture, 1999) Kapolka, Nicole MichelleItem Reclamation effectiveness at three reclaimed abandoned mine sites in Jefferson County, Montana(Montana State University - Bozeman, College of Agriculture, 2006) Tafi, Tara Christine; Chairperson, Graduate Committee: Dennis Neuman.Montana has an estimated 6000 abandoned mine sites, many with associated waste rock and tailings materials contributing to the release of high levels of acidity, heavy metals, and other contaminants, creating a risk to human health and the environment. Many abandoned mine sites in Montana have been reclaimed, however, little post-reclamation monitoring has been performed, and the effectiveness of reclamation has not been quantified. The goal of this project was to quantify the effectiveness of reclamation at three sites in Jefferson County, Montana based on soil suitability for sustaining plant growth. Vegetation and soil studies were executed using a stratified random sampling design. Vegetation measurements included canopy cover using Daubenmire cover classes, above ground biomass, and species richness/diversity. Co-located soil samples were excavated in increments to a depth of 60 cm, and determinations of pH, electrical conductivity, nutrients, soluble, and total metal levels were made. Canopy cover estimates ranged from 0-120% and biomass production estimates ranged from 0-4583 kg ha-1.