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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evaluating the Influence of Vegetation on Evapotranspiration from Waste Rock Surfaces in the Elk Valley, British Columbia

Fraser, Stephanie 11 1900 (has links)
Coal mines operated by Teck Coal Ltd., in the Elk Valley, British Columbia, utilize the method of surface mining, resulting in large waste rock piles that affect water quality. In order to limit the influence that these waste rock piles have on water-rock interaction, alternate management strategies are being explored. In this study, the influence of vegetation on evapotranspiration is examined, as potential benefits exist in using vegetation to reduce the infiltration and percolation of water into waste rock. During the 2013 growing season, energy and water balance components were measured using the eddy covariance technique at a bare waste rock surface, a waste rock surface with a vegetated grass cover, and a waste rock surface with a reclaimed forest cover. In addition, other water balance components were measured, such as soil water storage and precipitation. The placement of vegetation atop the waste rock pile allowed for increased evapotranspiration compared to the bare waste rock surface. From 23 May 2013 to 30 September 2013, the reclaimed forest and reclaimed grasses site experienced 305 mm and 272 mm of ET, respectively, while the bare waste rock site had only 140 mm of ET. This increase in evapotranspiration suggests less deep percolation at vegetated sites, estimated as 148 mm, 172 mm and 246 mm for the grass, forest and bare rock sites respectively. ET at the vegetated sites was dominantly controlled by the net radiation, while the near surface moisture was the dominant control on ET at the bare rock site. Results from this study suggest future reclamation projects should consider placing surface vegetation as a potential method to reduce deep percolation into waste rock piles. / Thesis / Master of Science (MSc)
2

Field Indicators for the Prediction of Appalachian Soil and Bedrock Geochemistry

Johnson, Daniel K. 03 August 2016 (has links)
Surface mining for coal in the Central Appalachians contributes total dissolved solids (TDS) to headwater streams, especially below larger mines and associated valley fills. My objective was to characterize the geochemical properties of a range of surface soils and associated geologic strata from the Central Appalachian coalfields and to relate those properties to simple field indicators, such as color or rock type. I hypothesized that these indicators can accurately predict certain geochemical properties. Thirty-three vertical weathering sequences were sampled from eight surface mines throughout the Central Appalachian coalfields, for a total of 204 individual samples. No differences were found among sites in overall saturated paste specific conductance (SC; used as a proxy for TDS) levels, but significant geochemical differences existed among samples. Sulfate release dominated SC levels, followed closely by Ca and Mg. Surficial soils and sandstones were yellowish-brown in color, high in citrate dithionite (CD) - extractable Al, Fe, and Mn, and low in SC, compared to underlying sandstones, shales, and mudstones, which were grayish to black, low in CD-extractable Al, Fe, and Mn, and significantly higher in SC. Saturated paste As and P were higher in A horizons, whereas Se was significantly higher in unweathered bedrock than in soil or weathered bedrock. Samples generating exothermic reactions with 30% H2O2 produced higher SC levels, sulfate, Mg, and Se. In conclusion, the mine spoils studied varied widely in geochemical properties. The simple field indicators presented here, such as color, weathering status, rock type, and H2O2 reaction can provide valuable guidance for identifying TDS risk which would greatly improve operator's ability to actively minimize TDS release. I recommend using soil and weathered, yellowish-brown sandstone layers as a source of low TDS spoil material whenever possible. The H2O2 field test is useful for identification of TDS and Se risk. Underlying unweathered bedrock layers should be treated as "potentially high TDS spoils". Particularly high risk spoils include gray to black mudstones and shales, coals, and coal associated shales, mudstones, and clays directly associated with coal seams. I recommend hydrologically isolating these spoils using techniques similar to those used historically for acid-forming materials. / Ph. D.
3

Early Successional Processes of Experimentally-Reclaimed Mine Sites in Eastern Ohio and the Restoration of American Chestnut

Gilland, Keith E. 10 June 2013 (has links)
No description available.
4

Avian population and community dynamics in response to vegetation restoration on reclaimed mine lands in southwest Virginia

Latimer, Chris E. 29 May 2012 (has links)
Coal surface-mining is often implicated for its negative impacts on native flora and fauna. However, some studies suggest that, in reclaiming land after mining, there may be potential to create early successional habitat needed by many avian species currently in decline throughout eastern North America. I evaluated nest-site selection and nest success for on reclaimed mine lands in southwest Virginia during the summers of 2010 and 2011. For this nest-site analysis, I focused on 2 bird species common to reclaimed mine lands in southwest Virginia: field sparrows (Spizella pusillia) and indigo buntings (Passerina cyanea). In addition, I assessed bird community attributes in relation to various surface-mine reclamation regimens over a 5-year period from 2007-2011. For both species, I found estimates of daily nest success to be higher than other estimates reported in the literature; however, empirical estimates of adult and juvenile survival are needed to provide better estimates of population status. For field sparrows, models of avian nest success support the hypothesis that a tradeoff exists between nest concealment and a view of the surroundings for field sparrows. For indigo buntings, year explained the most variation in nest success, with much lower estimates of daily nest survival in 2010, possibly as a result of increased precipitation. I also assessed avian community dynamics in relation to vegetation changes on reclaimed mine sites and observed a total of 96 species throughout the 4 years of sampling. Local species persistence and species turnover were comparable to another continental scale study conducted using breeding bird survey (BBS) data. Observed changes in community vital rates were likely a result of changes in certain habitat attributes over the 5-year period. Lastly, seven species were unique to certain cover types, suggesting the need to consider landscape level processes when developing restoration guidelines for reclaimed coal surface-mines. / Master of Science
5

Creative Participation: Rethinking Reclamation

Holloway, Lewis Weber 14 June 2005 (has links)
This project investigates the development of Western Man's relationship with nature by comparing and contrasting it with the relationship that Native Cultures, particularly Native American Cultures have with nature. This reveals Western Man's reliance on the concept of objectivity and the resultant objectification of the natural world. In so doing Western Man has put himself apart from the rest of the world, somehow above it. Although I do not argue that this is wholly unjust, I do argue that it has resulted in a loss of an essential component of the human experience. Creative Participation is identified as a way to bring together some of the lessons of the Native communities with the existing knowledge of Western Society. This knowledge is then applied to the practical problem of Mine Land Reclamation in Southern West Virginia. Creative Participation, at its heart, is a way to reconnect man with the reality of his connection to the rest of the world, rather than his separation and control of it. / Master of Landscape Architecture
6

Grassland Revegetation for Mine Reclamation in Southeast Arizona

Lawson, Holly Marie January 2011 (has links)
Mine land reclamation techniques were tested in arid Southeast Arizona for their potential to enhance reclamation success on two sites at different elevations (1400- and 1650-meters above sea level) on two sandy loam soils (Arkose and Gila Conglomerate). Seedbed preparation (smooth or rough surface) and straw mulch treatments (surface mulch, mulch incorporated into the soil, or no mulch) were tested for their potential to establish vegetation and prevent erosion. Gila soil retained 12.9% more soil moisture than the Arkose soil and was preferred by the seed mix (Gila: 64.4 plants m⁻²; Arkose: 23.2 plants m⁻²). A rough surface with surface mulch was recommended. Gila soil was more susceptible to erosion likely because it contained smaller soil particles. Rock cover was associated with significantly (P=0.0138) reduced rate of soil movement (0.1588 cm soil loss or accumulation per 1 percent rock cover). Proper soil management can be critical for reclamation success.
7

Soil Moisture Profiles and Root growth of Hardwood Trees Planted in Different Groundcovers on the Steep Slopes of Reclaimed Mine Sites

Aubuchon, Elizabeth Anne 01 December 2010 (has links)
Surface mining is a major industry in eastern Tennessee that removes much of the native forest. To restore the forest, reclamation practices are used. These include planting a ground cover species with native hardwoods. Competition between the ground cover and tree species for soil resources could hinder growth and decrease survival of the trees. Northern red oak (Quercus rubra) was used for this study to examine the possible effects of this competition and the relationships between root growth and soil moisture through a field and a greenhouse experiment. A field experiment was designed using four different ground cover treatments (Soldiago nemoralis, Medicago sativa, Panicum virgatum, and bare ground) with four different hardwood species. Northern red oak was measured for this study. The results showed that the site physical factors (slope position, soil temperature, and soil moisture) were not related to each other. Soil moisture varied by depth with the lower depths (46 cm to 76 cm) was much higher than the upper depths (0 to 46 cm). Root growth did not differ by treatment or percent cover. Both soil temperature and ground cover percentage increased over the growing season. Root growth showed a relationship with depth with the upper depths of soil having more roots than the lower depths. Annual rye was used as well as switchgrass, alfalfa, and bare ground treatments for a green house study. Two-year-old Northern red oak seedlings were first planted in pots and then ground covers were established and grown for 9 weeks. Then water stress was imposed over two dry down periods during which transpiration and soil moisture were measured. Root growth was measured after harvest. The results showed a relationship between transpiration and soil moisture. Soil moisture was highest in the bare ground treatment and lowest in the annual rye treatment. Fine root development of trees was greatest in the bare and alfalfa and lowest in the annual rye. Switchgrass had the second highest soil moisture and third highest fine root development. Root growth was related to both soil moisture and transpiration.
8

Multiple Approaches to the Restoration of Disturbed Desert Land

Banerjee, Monisha J. January 2009 (has links)
Three experiments were conducted to examine restoration of disturbed land in Arizona. The first experiment attempted to revegetate abandoned farmland by direct seeding native seeds and using various soil preparation techniques, amendments, and weeding of Salsola iberica. Only irrigation and weeding had a significant effect on seed germination and canopy cover. Irrigation increased plant cover on plots, but weeds dominated the cover. A seedbank study conducted near the end of the second growing season found the soil was dominated by weeds and contained few viable native seeds. The results illustrate the difficulty of establishing native plants on abandoned desert farmland due to the dominance of weedy species, the presence of salts in the soil, and the lack of adequate soil moisture.The second experiment, a lysimeter study, tested the efficacy of different evapotranspiration (ET) soil cover designs for stabilization of acidic copper mine tailing piles. The study evaluated the effectiveness of capillary barriers (CB) to contain the waste found in tailings and different plants to revegetate the piles. The ET covers reduced infiltration of water into tailings. Copper concentrations increased significantly in plant tissue grown on the ET covers compared to plants grown in the greenhouse. Plants did not exhibit signs of phytotoxicity and concentrations were below levels toxic to all domestic animals except sheep. The CB did not reduce water infiltration into the tailings or upward migration of copper into the soil cover. Vegetation is vital to an effective ET cover. A mix of transplanted shrubs and seeded grasses and forbs establish long-term, sustainable vegetation.The third experiment examined the influence of biosolids on the bacterial communities within mine tailings by bacterial counts and bacterial diversity. The diversity of neutral copper mine tailings two weeks after biosolid application was compared with that of desert soil via cloning and sequencing of PCR amplified community 16S rRNA. Culturable heterotrophic plate counts (HPC) increased following biosolid addition. Total direct counts exceeded HPC by approximately two orders of magnitude. Overall, biosolid-amended tailings contained large numbers of bacteria diverse in nature and with many of the traits of normal desert soil bacterial communities.
9

Recreating a functioning forest soil in reclaimed oil sands in northern Alberta

Rowland, Sara Michelle 05 1900 (has links)
During oil-sands mining all vegetation cover, soil, overburden and oil-sand is removed, leaving pits several kilometres wide and hundreds of metres deep. These pits are reclaimed by a variety of treatments using mineral soil or a mixed peat and mineral soil as the capping layer and planted with trees with natural colonisation from adjacent sites. A number of reclamation treatments covering different age classes were compared with a range of natural forest ecotypes to identify the age at which the treatments become similar to a natural site with respect to vegetation composition and key soil attributes relevant to nutrient cycling. Ecosystem function was estimated from plant community composition, litter decomposition, development of an organic layer and bio-available nutrients. Key response variables including moisture, pH, C:N ratios, bio-available nutrients and ground-cover were analysed by non-metric multidimensional scaling and cluster analysis to discover which reclamation treatments were moving towards or merging with natural forest ecotypes and at what age this occurs. On reclaimed sites, bio-available nutrients including nitrate generally were above the natural range of variability but ammonium, phosphorus, potassium, sodium and manganese were generally very low and limiting to ecosystem development. Plant diversity was similar to natural sites from 5 years to 30 years after reclamation, but declined as reclaimed sites approached canopy closure. Grass and forb leaf litters decomposed faster than aspen or pine in the first year, but decomposition on one reclamation treatment fell below the natural range of variability. Development of an organic layer appeared to be facilitated by the presence of shrubs, while forbs correlated negatively with first-year decomposition of aspen litter. The better restoration amendments for tailings sands involved repeated fertilisation of peat: mineral mixtures in the early years of plant establishment, these became similar to a target ecotype at about 25 years. Good results were also shown by subsoil laid over non-saline overburden and fertilised once, these became similar to a target ecotype at about 15 years. Other treatments receiving a single application of fertiliser remain entrenched in the early reclamation phase for up to 25 years.
10

Influence of Spoil Type on Afforestation Success and Hydrochemical Function on a Surface Coal Mine in Eastern Kentucky

Sena, Kenton L. 01 January 2014 (has links)
Surface coal mining in Appalachia has contributed to a suite of ecological impacts, both terrestrial and aquatic. Conventional reclamation in Appalachia leads to the development of hay/pasture systems dominated by nonnative grasses and legumes, with soils that are chemically and physically unfavorable to native tree growth. Several studies have shown that more weathered minespoils provide a better growth medium than unweathered spoils in Appalachia. Spoil segregation plots were constructed on Bent Mountain in Pike County, KY, to compare the suitability of three mine spoil types (BROWN weathered sandstone, GRAY unweathered sandstone, and MIXED sandstones and shales). In 2013 (after nine growing seasons) volume of planted trees was 50x higher on BROWN than on GRAY. In addition, natural colonization of unplanted groundcover and tree species was much more extensive on BROWN than GRAY or MIXED. Most water chemical parameters were similar across spoil types; however, water chemistry on all plots appears to have stabilized after nine growing seasons. Finally, rapidly developing forest on BROWN appears to be influencing water budgeting on the site, leading to lower discharge during summer months. These results indicate that BROWN weathered spoils provide a better growth medium than GRAY unweathered spoils for native trees.

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