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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.
51

Analysis of Reconstructed Mine Soils on Reclaimed Coal and Mineral Sands Mined Lands in Virginia

Angel, Hannah Zoe 01 September 2022 (has links)
Post-mining land use potentials are greatly influenced by mine soil properties. I analyzed and classified coal mine soils in SW VA and mineral sands mine soils in SE VA to aid development of appropriate post-mining land use interpretations. For coal mine soils, long-term pedogenesis was assessed in sandstone (SS) and/or siltstone (SiS) spoils with and without surface amendments. For mineral sands mined lands, I evaluated their spatial variability with respect to underlying relic mining influences and rowcrop productivity. Coal mine subsoils densified as root-limiting layers formed that were not observed initially and all soils had weak pedogenic development (^Bw; cambic horizons), particularly SS derived soils. Initial rock spoil type strongly influenced coal mine soils over time (i.e., SS had coarser textures and lower subsoil pH vs. SiS). However, most soil chemical properties (e.g., pH, EC, CEC) became similar in ^A horizons over time. Fe-oxides increased, and extractable-P decreased with weathering, raising concerns for long-term P-availability. Organic amendments applied to rock spoil surfaces sustained higher total-N (sawdust and biosolids) and extractable P (biosolids). Soil carbon sequestration rates did not differ among rock types or amendments (0.16 to 0.28 Mg ha yr-1). Further, mineral sands mine soils were limited by densic contacts and short-range variability of important properties (texture) appeared related to underlying relic mining features (pits and berms). Yields in reclaimed soils were more variable than in adjacent undisturbed farmland, but mean yields were only slightly reduced for soybean in 2020. Coloration and Fe-oxide spectral indices had weak to moderate negative correlations with yield. Berm positions supported better soybean growth (three out of five sites), while pit positions were redder/darker (one out of five sites). Current Soil Taxonomy conveys anthropogenic origins at the family (e.g., spolic) and subgroup (e.g., Anthroportic) levels. Existing taxa and proposed Artesols order criteria both acknowledge effective soil depth x compaction limitations (Anthrodensic subgroup), but Artesols more effectively recognizes pedogenesis (Inceptic subgroup) and acknowledges mine soils at the highest level. The biggest management limitation for both mine soil types is root-limiting compaction; thus, future efforts should focus on defining depth ranges and taxonomic interpretations for densic contacts. / Doctor of Philosophy / Surface mining results in drastic disturbances to the original soil, land, and water features. Actual impacts vary due to local site conditions and methods used for mineral extraction and reclamation. Advancing reclamation science requires an understanding of the resulting mine soil properties and how they vary spatially and develop over time. This research program involved two very different mining scenarios and resultant mine soil types in Virginia that were both evaluated in terms of soil properties, taxonomic placements, and land use interpretations. First, I assessed Appalachian coal mine soils in southwestern Virginia following 34 years of soil development in sandstone (SS) and/or siltstone (SiS) derived overburden with and without surface amendments. Over time, rocky mine spoils transformed into weakly developed soil profiles, commonly with four to five total distinct layers (horizons), along with apparent "self-compacted" layers at depth. SS soils were coarser textured with somewhat better subsoil structure, while SiS soils were finer textured and had higher subsoil pH. However, many chemical properties were similar in the soil surface. Organic amendments and topsoil return imparted only subtle differences over time. A secondary objective was to assess mineral sands mine soils, which originate from recombined Coastal Plain sediments. Due to the nature of their wet deposition during final reclamation, these mine soils exhibited high variability across local landforms. Soil profiles over former berm positions were composed mostly of sandier materials, while pit positions had more variable materials and features. Reclaimed rowcrop yields were moderately correlated with bare soil remotely sensed variables. Soils in pit positions were redder in color due to higher clay. While yields were variable, especially in drier years, berms appeared to support better soybean growth, but results were inconsistent across fields. For both mine soil types, root-limiting compaction is their biggest impediment to productive use. Forestry is the predominant post-mining land use on former coal mines, while rowcrop production is becoming more common on former minerals sands mines. Since these two different post-mining environments present unique challenges for correctly interpreting their post-disturbance land-uses, it is important to convey their special properties (e.g., densic contacts) and limitations in their classification.
52

A remediation and sustainable rehabilitation strategy for Manuel Street Park, Johannesburg Gauteng : microbial treatment, landscaping and public needs assessment

Maphorogo, Alusani Adzifheli Emmanuel 21 January 2016 (has links)
Introduction Run-off from Johannesburg mine dumps is a source of environmental pollution and a public health concern. This study focussed on assessing and developing remediation strategies for Manuel Street Park (MSP) that has been affected by run-off from the Princess Mine dump. Study objectives were threefold: to use a survey involving residents living around MSP to determine community use and perception of rehabilitation of the Park; to determine the impact of the addition of a preparation known as “Effective Micro-organisms” (EM®) to polluted Park soil and; to prepare a remediation plan for this Park. Methodology A qualitative survey was conducted amongst users of the park as to their use and perceptions of rehabilitation of the park and their understanding of mine-related pollution and acid mine drainage. Controlled greenhouse trials were conducted to determine optimal germination and growth of Pennisetum clandestinum (Kikuyu grass) in Park soil, with and without EM® or compost. A landscaper was consulted to collate research results to facilitate park rehabilitation. Results Survey participants understood the risks of Acid Mine Drainage (AMD) and other mine pollution and gave valuable information which assisted in understanding local issues concerning the park. Tests with soil polluted with AMD showed that it promoted seed germination while treatment of park soil with fertiliser, compost and enhanced microorganisms improved plant development and growth. Practically, it was determined that the use of EM1 at the park would be difficult because of on-going flooding of the park with contaminated water. For this reason, an improved drainage plan was suggested, along with raised walkways. Conclusion A remediation plan can be implemented on site involving installation of French drains, raised walkways, and soil remediation involving EM® / Agriculture, Animal Health and Human Ecology / M. Sc. (Environmental Management Ornamental Horticulture)
53

Obnova druhově bohatých luk na výsypkách po těžbě uhlí, vliv růyných technik a velikosti obnovované plochy / Obnova druhově bohatých luk na výsypkách po těžbě uhlí, vliv růyných technik a velikosti obnovované plochy

Kolářová, Petra January 2014 (has links)
Common problems and characteristics of sites affected by the mining are land occupation, pollution, land degradation, hydrologic changes and landscape change what belong to the major environmental problems in many countries. Despite the regulation prescribed by the Mining Act which brought significant progress in post mining land reclamation, emphasise mostly in recovery of production capability of landscape, many recent studies state it may not be so effective in restoration of diversity and ecosystem services. In order to properly assess newer approaches in spoil heaps recultivation our research is focused on the restoration of species rich meadows using near-nature methods, specifically the transfer of turves and seeds-containing hay transfer supported by management (mowing and mowing with mulching). Additionally, the research is focused on influence of the plot size on restoration success and on effect of management on soil development. Both of the applied near-nature methods of species rich meadow recultivation are effective in species provisioning and thus succession acceleration. More successful is the method of transferred turves where it was possible to establish more than 60% of the species from the donor site. The species richness on sites and its spreading is dependent on implemented...
54

A remediation and sustainable rehabilitation strategy for Manuel Street Park, Johannesburg Gauteng : microbial treatment, landscaping and public needs assessment

Maphorogo, Alusani Adzifheli Emmanuel 21 January 2016 (has links)
Introduction Run-off from Johannesburg mine dumps is a source of environmental pollution and a public health concern. This study focussed on assessing and developing remediation strategies for Manuel Street Park (MSP) that has been affected by run-off from the Princess Mine dump. Study objectives were threefold: to use a survey involving residents living around MSP to determine community use and perception of rehabilitation of the Park; to determine the impact of the addition of a preparation known as “Effective Micro-organisms” (EM®) to polluted Park soil and; to prepare a remediation plan for this Park. Methodology A qualitative survey was conducted amongst users of the park as to their use and perceptions of rehabilitation of the park and their understanding of mine-related pollution and acid mine drainage. Controlled greenhouse trials were conducted to determine optimal germination and growth of Pennisetum clandestinum (Kikuyu grass) in Park soil, with and without EM® or compost. A landscaper was consulted to collate research results to facilitate park rehabilitation. Results Survey participants understood the risks of Acid Mine Drainage (AMD) and other mine pollution and gave valuable information which assisted in understanding local issues concerning the park. Tests with soil polluted with AMD showed that it promoted seed germination while treatment of park soil with fertiliser, compost and enhanced microorganisms improved plant development and growth. Practically, it was determined that the use of EM1 at the park would be difficult because of on-going flooding of the park with contaminated water. For this reason, an improved drainage plan was suggested, along with raised walkways. Conclusion A remediation plan can be implemented on site involving installation of French drains, raised walkways, and soil remediation involving EM® / Agriculture, Animal Health and Human Ecology / M. Sc. (Environmental Management Ornamental Horticulture)
55

Prověrka funkčnosti jednotlivých USES v oblasti Sokolovské pánve a návaznost na okolní krajinu / Utility verification of single cells of territorial systems of ecological stability in Sokolov basin area and sequence on surrounding countryside

MORÁVKOVÁ, Veronika January 2008 (has links)
Countryside is a dynamic system which has been constantly developing. A man may be a factor which speeds up, slows down or completely stops the development. Spoil bank in Podkrušnohoří is an illustration of the violation, where a shut-down of countryside development due to logging operations happened. The goal of every activity, which negatively modifies countryside, should be sequent reparation. In case of Podkrušnohoří spoil bank such a recultivation should be proposed and countryside items, which would increase ecological countryside stability and would help to awaken the countryside into its historical form, should be found.
56

A Geochemical and Mineralogical Comparison of Soil Formation on Mine Spoil and Undisturbed Shale and their Contributions to Pore Water, Huff Run Watershed, Ohio

Zemanek, Laura Marie 11 October 2021 (has links)
No description available.
57

Secondary Mineral Coating Formation and Metal Sequestration in Soils Developing from Mine Spoil Pre- and Post-Treatment with Lime

Cole, Kortney Ann 01 November 2021 (has links)
No description available.
58

Effect of soil covers on coal waste dumps in KwaZulu-Natal on abiotic factors and bacteria causing acid mine drainage

Cleghorn, Charles, 1970- 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 1997. / ENGLISH ABSTRACT: The activity of iron-oxidizing bacteria, for example, Thiobacillut. ferrooxidans, in the outer layers of coal waste dumps results in the oxidation of pyrite with the formation of large volumes of acid mine drainage. The process requires atmospheric oxygen and moisture. Acid mine drainage may possibly be controlled by creating unfavourable environmental conditions in dumps for the iron-oxidizing bacteria. The present research investigated the possibility of inhibiting these bacteria and consequently acid formation in coal waste dumps by means of different dump construction techniques. Physical and chemical conditions, acid formation and populations of four groups of bacteria which might produce acid were studied in the outer layers of ten differently constructed pilot scale coal waste dumps at the Kilbarchan Mine near Newcastle, Kwazulu-Natal, from September 1993 to July 1995. Dump covers consisting of a 30-cm or 70-cm layer of Estcourt soil of low permeability covered with 70 cm or 30 cm, respectively, of more permeable Avalon soil produced anaerobic conditions in the dumps throughout most of the 22 months of the test period, as did a cover of 70 cm compacted plus 30 cm uncompacted Avalon soil alone. An uncoMpacted 30-cm or compacted 50- cm Avalon soil cover proved ineffective in causing prolonged anaerobic conditions. Uncovered dumps showed only slight reduction of oxygen in the coal waste after heavy rains. Pockets of acidity were detected on several occasions in the coal waste below the 50-cm Avalon soil layer from the time of construction and progressively increasing acidity in the uncovered dumps and the waste below the 30-cm Avalon soil cover. Iron-oxidizing bacterial populations of the T. ferrooxidans type have tended to be higher in the uncovered dumps and Avalon soil-covered dumps showing acidification than in the non-acidified dumps covered with 1 m of Avalon soil or Avalon and Estcourt soil. Associated populations of iron-oxidizing bacteria of the Metallogenium type, acidophilic and non-acidophilic thiosulphate-oxidizing bacteria were generally low in the coal waste of the dumps. Thus, five of the soil covers, all with a thickness of 1 m, but not covers with a thickness of 0.5 m or less, proved effective for almost 2 years in inhibiting the diffusion of oxygen to the underlying coal waste in the pilot scale dumps and also appeared to suppress the populations of iron-oxidizing bacteria believed to be implicated in acid formation in the coal waste. These results suggest that coal waste dumps in South Africa should be covered with soil layers of 0.5-1.0 m thick to prevent the generation of acid mine drainage. / AFRIKAANSE OPSOMMING: Die aktiwiteit van ysteroksiderende bakteriee soos Thiobacillus ferrooxidans, in die buitenste lae van steenkoolafvalhope, veroorsaak die oksidasie van piriet met die gevolg dat groot volumes suur mynafloopwater gevorm word. Hierdie proses benodig suurstof en vog. Suur mynafloopwater kan moontlik beheer word deur 'n situasie te skep waar die toestande in die hope ongunstig is vir die ysteroksiderende bakteriee. Die huidige navorsing het die moontlikheid ondersoek om hierdie bakteriee te inhibeer deur verskillende afvalhoopontwerpe op die proef te stel en sodoende suurvorming in steenkoolmynhope te beperk. Die fisiese en chemies kondisies, suurvorming en populasies van vier verskillende bakterie-groepe wat dalk by suurvorming betrokke is, is vanaf September 1993 tot Julie 1995 bestudeer in die buitenste lae van tien verskillend gekonstrueerde loodsskaalafvalhope by die Kilbarchan myn naby Newcastle in KwaZulu-Natal. Afvalhoopbedekkings bestaande uit 'n 30-cm of 70-cm Estcourt grond met 'n lae permeabiliteit bedek met'n 70-cm of 30-cm laag van meer deurlaatbare Avalon grond het anaerobe kondisies veroorsaak. Ongekompakteerde 30-cm en gekompakteerde 50-cm Avalon grondlae het egter nie bestendige anaerobe kondisies in die hope veroorsaak nie. Die onbedekte hope het aerobics gebly met slegs effense dalings van suurstofkonsentrasies gedurende en na swaar reens. Geisoleerde monsters uit die steenkoolafval onder die 50-cm Avalon grondlaag het vanaf die begin van die toetsperiode tekens van suurvorming getoon. Die onbedekte steenkoolafval en die van die sel met 'n 30-cm Avalon grondlaag het met verloop van tyd al hoe meer suur geword. Die ysteroksiderende bakterie-populasies van die T. ferrooxidans tipe het geblyk om in die onbedekte en Avalon grondbedekte hope wat tekens van suurvorming getoon het hoer te wees as in die hope wat met 'n 1-m laag Avalon grond of Avalon en Estcourt grond bedek is en geen tekens van suurvorming getoon het nie. Ysteroksiderende bakteriepopulasies van die Metallogenium tipe, nieasidofiele en asidofiele tiosulfaatoksiderende populasies was oor die algemeen laag in die steenkoolafvalhope. Vyf van die grondlae wat alma! 1 m dik was het dus geblyk om effektief te wees in die bekamping van die infiltrasie van suurstof na die onderliggende steenkoolafval in die loodskaalhope. Dit lyk asof daardie lae die ysteroksiderende populasies betrokke by suurvorming onderdruk het. Die 0.5-m grondbedekking het egter nie so 'n sterk onderdrukkende effek op die suurstofinfiltrasie of die bakteriepopulasie gehad nie. Na aanleiding van hierdie resultate blyk dit dat steenkoolafvalhope in Suid-Afrika met minstens 0.5 tot 1..0 m grond bedek moet word om effektief die probleem van suur mynafloopwater te bekamp.
59

Impact du lignite sur les caractéristiques physico-chimiques et microbiologiques des sols : application aux sols du bassin minier de Provence / Impact of lignite on the physico-chemical and microbiological characteristics of soils : application to soils of mine basin of Provence

Clouard, Mélanie 18 December 2013 (has links)
Les terrils du bassin minier de Provence sont implantés dans le paysage et demeurent à proximité des habitations de la métropole Aix-Marseille. Les terrils les plus anciens ont été naturellement colonisés par la végétation et des sols s’y sont développés avec une vitesse remarquable. Cette étude vise à comprendre les processus pédogénétiques en cours depuis 55 ans sur les terrils miniers. Nous avons étudié l’impact du lignite sur les caractéristiques physico-chimiques et microbiologiques d’un Rendosol naturel. Deux sols similaires, dont l’un est traversé par l’affleurement naturel d’une veine de lignite et l’autre pas, ont donc été comparés afin de caractériser les variables impactées par le lignite. L’étude du terril Armand a permis de comprendre les facteurs responsables de la formation et de la variabilité des caractéristiques des sols observés sur le terril. L’abondance de composés carbonés récalcitrants dans les sols enrichis en lignite affecte les niveaux d’activité des microorganismes responsables des processus biologiques dans les sols sans induire d’effets néfastes. Le lignite semble intervenir comme un facteur de dilution du carbone organique, diminuant ainsi la quantité de carbone disponible et donc la vitalité d’expression des fonctions microbiennes. Les activités biologiques sont diminuées en présence de lignite, mais les changements induits sur les propriétés physico-chimiques semblent améliorer la fertilité du sol. Les sols du terril Armand demeurent cependant encore à un stade d’évolution trop jeune pour préjuger de leur évolution future. / Spoil heaps are scattered over the coal basin of Provence: they are inserted in the landscape and often located close to urban areas of the Aix-Marseille Metropole. The oldest spoil heaps have been naturally colonized by local vegetation and soils have simultaneously quickly developed. This study aims at understanding the processes involved in soil forming on undisturbed lignite-rich spoil heaps since 55 years. We studied the impact of lignite on the physico-chemical and microbiological characteristics of an undisturbed soil: we compared two similar Rendosols, except that one was developed in a natural lignite outcrop. Then we studied on the 55-year-old Armand spoil heap the factors responsible for soil genesis and variability of soil characteristics. Recalcitrant carbon compounds found in soils enriched with lignite modify microbial activity but do not induce negative effects. It seems that lignite acts as a diluting factor of the organic carbon that decreases the available carbon pool and consequently on the vitality of the expression of the microbial functions. Enzymatic activities and basal respiration decrease while changes observed on physico-chemical properties tend to improve soil fertility. Some characteristics of the soils developed on the spoil heap are similar to those of the soil developed from the lignite outcrop, while others are more related to the way the spoil heap was set up. Although these results have shed light on some of the processes involved in soil formation on spoil heaps in a carbonated environment, soils on Armand spoil heap are still at an early stage of development that precludes conclusion on their future evolution.
60

Migration of Dredged Material Mounds: Predictions Based on Field Measurements of Waves, Currents, and Suspended Sediments, Brunswick, GA

Johnson, Charley R. 20 April 2005 (has links)
The state of Georgia has two large ports that are accessed by way of navigable entrance channels. One of these ports is located in Brunswick, Georgia, and is maintained by the United States Army Corps of Engineers via periodic dredging. Sediments removed from the channel are typically pumped several miles offshore of Brunswick and placed in dredged material mounds, thus removing the sediment from the littoral cycle. This offshore placement, while being the most economically viable method, often negatively impacts the sediment budget of the coastal region and causes erosion downdrift of the channel, specifically along Jekyll Island. Onshore placement of the dredged material is not feasible due to increased associated costs and the high fraction of fines present in the material; thus, nearshore placement is a potentially viable alternative. Nearshore placement could possibly reduce erosion rates and provide protection to property from waves and storms. The USACE initiated a thorough field data collection campaign in 2002 to study the possibility of beneficial placement of dredged material. The author analyzed the existing data to predict the rate and direction of sediment movement away from an existing dredge mound. These predictions are then compared to bathymetric survey data in an effort to validate the results and methodologies used for sediment transport predictions. The ultimate goal is to use the results of this study along with numerical models currently being developed by the Corps to assess the possibility of sediments being transported toward the shore thus re-entering the littoral cycle and providing a benefit to the coast of Georgia.

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