Browsing by Subject "manganese"

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    Identification of Microorganisms for the Bioremediation of Nitrate and Manganese in Minnesota Water
    (2018-08) Anderson, Emily
    Bioremediation is a way to safely and cost-effectively remove contaminants using living organisms. In this thesis, microorganisms capable of remediating two pollutants, nitrate and manganese, were identified using culture-dependent and –independent approaches. Nitrate in agricultural wastewater can lead to algal blooms and eutrophication. Edge-of-field woodchip bioreactors are a promising approach to prevent nitrate in wastewater from reaching surface waters by utilizing microbial denitrification to remove nitrate from the system. However, woodchip bioreactors experience low efficiency under cold temperatures, so one strategy to enhance bioreactors in the early spring involves bioaugmentation, or inoculating the bioreactors with cold-adapted denitrifying microorganisms. In order to identify a cold-adapted denitrifier for bioaugmentation, microorganisms were isolated from field woodchip bioreactors and subjected to denitrification testing under cold temperatures, measuring nitrate, nitrite, ammonium, nitrous oxide and dinitrogen gas, as well as whole genome sequencing to identify the presence of genes involved in denitrification and other important microbial processes. Based off of these results, two strains, Microvirgula sp. BE2.4 and Cellulomonas sp. WB94 were recommended for bioaugmentation. In part two, manganese was addressed. High levels of manganese in drinking water can cause health problems, and common treatment methods require cost-intensive chemicals, conditions and maintenance. In this study, a novel algae bioreactor was established to remove manganese from water. In this bioreactor, the algae provided fixed carbon for manganese-oxidizing microorganisms that oxidized the dissolved manganese, precipitating it out of solution. Using a culture-dependent approach, manganese-oxidizing bacteria and fungi were isolated from an environmental sample, including known oxidizers Bosea, Pseudomonas, Plectosphaerella and Phoma and some not previously known to oxidize manganese such as Aeromonas, Skermanella, Ensifer and Aspergillus. A culture-independent approach was also employed to determine how abundant the isolated manganese-oxidizing bacteria are in an actively oxidizing environmental sample. Using nitrate and manganese as examples, this thesis identified useful microorganisms involved in remediation and demonstrated how microorganisms can be utilized to effectively remove pollutants from the environment.
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    Information Circular 32. Geology and Manganese Resources of the Cuyuna Iron Range, East-Central Minnesota
    (Minnesota Geological Survey, 1990) Morey, G.B.
    Ever since their discovery in 1904, it has been recognized that the iron-formations and associated ore deposits of the Cuyuna iron range in east-central Minnesota contained appreciable quantities of manganese which was extracted as ferromanganese ores from several mines on the North range from 1911 to 1984. The presence of this manganese resource sets the Cuyuna range apart from other iron-mining districts of the Lake Superior region. The emphasis of this report is on the geologic factors that seem to control how the manganese is distributed on the Cuyuna range. However because the range was exploited principally for its iron ores, much of the available information is fragmentary. Although the manganese is closely associated with the iron ores, it was carefully evaluated by only a few of the companies operating on the range. Other companies examined the manganese-bearing material in only a cursory manner, and therefore in spite of what appears to be an extensive data base, our knowledge of the geology of the manganese resources is fragmentary and in part confusing. It is not yet possible to construct a coherent, detailed picture of the primary origin of the manganese-bearing strata, the structure and stratigraphic positions of these strata, and the precise tenor, extent, and localization of the several different kinds of manganese-bearing material that have been recognized. The ultimate utilization of the Cuyuna manganese deposits will require new metallurgical and beneficiation techniques that must be designed specifically for the different kinds of ores, and this report, if nothing else, should call attention to the deficiencies of the present geological data base.