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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.
41

Physical, chemical and mineralogical properties of mine spoil derived from the Wise Formation, Buchanan County, Virginia

Howard, Jeffrey Lynn January 1979 (has links)
Physical disintegration of the rocks is promoted by the closely spaced blast-hole grid used in the mining operation. Wet-dryfreeze-thaw forces are effective in causing disarticulation of the weakened rocks in 6 months or less. The silty spoils cause excessive dust, are crusted and support ponds. Application of organic amendments promotes infiltration. Some of the spoils contain enough salts to seriously retard growth of non-tolerant plant species. Exchangeable bases are overestimated, but the salts are a nutrient source. K is low, but adsorption isotherms indicate that, unlike the naturally occurring soils of the locality, there is no serious problem of K-fixation in the spoils. NaHCO₃ gives the most accurate measure of spoil P. A response to fertilization is likely. Adsorption isotherms suggest a problem with P-fixation by the goethite rocks. There was no measurable pedogenic activity in the spoils after two years of weathering other than physical disintegration of rock fragments and weakly developed structure in some spoil surface layers. There was no evidence of leaching of salts during this period. When regrading the spoils on the benches, maintenance of adequate drainage is essential to prevent nutrient depletion, Fe-generated toxicity and acidity and toxic accumulations of salts. A mixture of 70% sandstone, 20% siltstone and 10% shale should yield a well-drained sandy loam spoil upon weathering. The ferruginous and silty rocks should be regraded well below the surface. / Master of Science
42

Micro-organisms involved in iron oxidation and acid mine drainage formation in KwaZulu-Natal and their control by soil covers on coal waste dumps

Modinger, Heinrich 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 1998. / One copy microfiche. / ENGLISH ABSTRACT: The biologically catalysed oxidation of pyrite in the outer layers of coal waste dumps leads to the formation of acid mine drainage. The oxidation of pyrite to ferric iron and sulphate is a complex process involving various abiotic and biologically catalysed reactions. Pyrite is abiotically oxidized by ferric iron, with the formation of thiosulphate and ferrous iron. Thiosulphate decomposes to form various inorganic sulphur compounds. Bacterial catalysis of pyrite oxidation is achieved by iron-oxidizing bacteria oxidizing ferrous iron to ferric iron. Bacteria that oxidize sulphur compounds assist the catalysis by oxidizing thiosulphate and its decomposition products. Heterotrophic organisms may play a role by consuming organic substances inhibitory to the lithotrophic bacteria. Abiotic ecological factors, acid formation and populations of iron-oxidizing bacterial groups were studied in 10 differently constructed pilot scale coal waste dumps, as the second phase of a study which started in September 1993. Gas samples were withdrawn weekly from coal waste through permanently buried stainless steel probes, for analysis in the field using a portable oxygen/carbon dioxide meter. Samples of coal waste were extracted by auger for analysis of moisture, pH and microbial populations. The analyses of oxygen and pH can be recommended for the routine monitoring of rehabilitated waste dumps. Covers of Avalon soil 0.3 or 0.5 m thick, were not adequate to prevent acidification. Coal waste covered with 0.7 m compacted beneath 0.3 m uncompacted Avalon soil, showed a slow pH decline, but reached approximately pH 3 in 1997. Covers of compacted Estcourt soil beneath tmcompacted Avalon soil to a cover depth of 1 m were effective in preventing acidification and generally kept the coal waste anaerobic. However, all covers developed cracks during drought conditions in 1995, allowing aeration. Low pH of some samples from these dumps during 1995/1996 may have indicated the start of acidification. Bacteria oxidizing high concentrations of ferrous iron and considered to be Thiobacillus ferrooxidans, were monitored routinely, but may not have been the dominant iron-oxidizer, as population counts using media with a lower ferrous iron concentration were higher. The majority of the latter organisms could also not oxidize sulphur, hence were not T. ferrooxidans. The populations of the high ferrous iron-oxidizing bacteria were affected by pH, tending to be high in acidified and low in non-acidified coal waste. Investigations of microbial populations forming iron-oxidizing consortia in enrichment cultures from coal waste and acid drainage samples showed the presence of T. ferrooxidans, the heterotrophic bacterial genus Acidiphilium, fungi of the genus Penicillium, unidentified filamentous fungi, including Cladophialophora-like morphological types, and a yeast of the genus Dipodascus. In interaction studies, the Penicillium isolate had an inhibitory effect on T. ferrooxidans (subjected to organic compound stress), but the Cladophialophora-like fungi reduced inhibition by organics. Fungi have not previously been studied in detail as components of iron-oxidizing consortia, but the bacterial isolations agree with those elsewhere, indicating that appropriate conclusions from acid mine drainage research in other parts of the world can be applied in KwaZulu-Natal. / AFRIKAANSE OPSOMMING: Die biologies gekataliseerde oksidasie van piriet in die buitenste lae van steenkoolafvalhope lei tot die vorming van suur mynafloopwater. Die oksidasie van piriet tot ferri-yster en sulfaat is 'n komplekse proses wat abiotiese en biologies gekataliseerde reaksies insluit. Piriet word abioties deur ferri-yster geoksideer, met die vrystelling van tiosulfaat en ferro-yster. Tiosulfaat verval om verskeie anorganiese swawelverbindings te vorm. Bakteriese katalise van pirietoksidasie word deur ysteroksiderende bakteriee wat ferro-yster na ferri-yster oksideer, bewerkstellig. Bakteriee wat swawelverbindings oksideer maak 'n bydrae tot die katalise deur tiosulfaat en vervalprodukte daarvan te oksideer. Heterotrofe organismes mag ook 'n rol speel deur organiese verbindings wat die litotrofe bakteriee mag inhibeer, te verbruik. Abiotiese ekologiese faktore, suurvorming en bevolkings ysteroksiderende bakteriee is in 10 verskillend gekonstrueerde loodsskaal steenkoolafvalhope bestudeer, as die tweede fase van 'n studie wat in September 1993 begin het. Gas monsters is weekliks uit die steenkoolafval onttrek deur vlekvrye staal peilers wat permanent daarin begrawe is, en met behulp van 'n draagbare suurstoflkoolstofdioksiedanaliseerder in die veld ontleed. Monsters van die steenkoolafval is met behulp van 'n kleiboor vir die analise van vog, pH en mikrobepopulasies geneem. Die analise van suurstof en pH kan aanbeveel word vir die roetiene monitering van gerehabiliteerde afvalhope. Bedekkings van 0.3 of 0.5 m Avalongrond was nie voldoende om suurvorming te verhoed nie. Steenkoolafval wat met 0.7 m gekompakteerde en 0.3 m ongekompakteerde Avalongrond bedek is, het 'n stadige pH-daling getoon, maar het in 1997 ongeveer pH 3 bereik. Bedekkings van gekompakteerde Estcourtgrond onder ongekompakteerde A valongrond met 'n totale dikte van 1 m, was effektief in die voorkoming van suurvorming. Hulle het oor die algemeen die steenkoolafval anaerobies gehou, maar aile bedekings het tydens die droogte in 1995 krake ontwikkel, wat suurstof laat binnedring het. 'n Lae pH gedurende 1995/1996 by sommige monsters uit hierdie hope mag die begin van suurvorming aangedui het. Bakteriee wat hoe konsentrasies ferro-yster oksideer en wat as Thiobacillus ferrooxidans beskou is, was moontlik nie die dominante ysteroksideerder nie, aangesien bevolkingstellings waar 'n medium met 'n laer konsentrasie ferro-yster gebruik is, hoer bevolkings getoon het. Die meerderheid van laasgenoemde organismes kon ook nie swawel benut nie en dus nie T. ferrooxidans was nie. Die bevolkings van die hoe ferro-ysteroksiderende bakteriee is deur pH beInvloed, met 'n geneigdheid tot hoe bevolkings in suur en lae bevolkings in minder suur steenkoolafval. Ondersoeke na die rnilcrobebevollcings wat in ysteroksiderende konsortia in verryldngslculture vanaf steenkoolafval- en suur mynafloopwatermonsters voorgekom het, het die teenwoordigheid van 7'. ferrooxidans, die heterotrofe balcteriegenus Acidiphilium, fungi van die genus Penicillium, ongeIdentifiseerde fungi, insluitend Cladophialophora-agtige tipes en 'n gis van die genus Dipodascus aangetoon. By interaksiestudies het die Penicillium-isolaat 'n inhiberende effek op T ferrooxidans (onderworpe aan organiese verbindingstres) gehad, maar die Cladophialophora-agtige fungi het die inhibisie deur organiese verbindings verminder. Fungi is nog the in detail as komponente van ysteroksiderende konsortia bestudeer the, maar die isolasies van bakteried stem saam met die van elders wat aandui dat toepaslike gevolgtreldcings ten opsigte van suur mynafloopwatemavorsing vanaf ander dele van die wereld ook in KwaZulu-Natal toegepas kan word.
43

Lime Treatment of Coal Mine Spoil Impacted Soils in the Huff Run Watershed of Northeast Ohio

Wood, Daniel L., 30 July 2018 (has links)
No description available.
44

Hodnocení sekvestračního potenciálu vegetace/porostů rekultivovaných výsypek metodami DPZ / Assessment of the sequestration capacity of vegetation by remote sensing methods in areas of reclaimed mining dumps

PIKL, Miroslav January 2018 (has links)
The study aims at estimation and mapping the amount of carbon allocated in above ground biomass of wood and in organo-mineral soil horizon at sites where reclamation and spontaneous succession took place on spoil heaps after coal mining. Several categories of data have been used to meet the objectives, namely ground field measurements, laboratory analyses of soil samples, airborne hyperspectral data from VNIR region, and airborne LiDAR scanning data. The digital imagery analysis, GIS modeling and multivariation statistical methods were applied in data assessment. The results show that there is a 7 600 tons of carbon allocated in above ground wood biomass in the area of 209 ha, and 8 100?12 200 tons in the soil A horizon in the region of the same size. The results proofed: 1/ statistically significant negative relationships (p < 0,01) between slope and amount of soil carbon, where higher negative correlation was for broad leaved species; 2/ statistically significant difference (p < 0,05) between amount of soil carbon under broad leaved and needle classes and under different species, the highest between soils under Alnus sp. and Pinus sp.; 3/ statistically significant relationships (p < 0,05) between the amount of carbon allocated in the aboveground wood biomass and that in the soil A horizon under the needle leaved class and under the spontaneous wood vegetation.
45

Biodiverzita a populační dynamika drobných zemních savců na několika typech rekultivací na Velké podkrušnohorské výsypce / Biodiversity and population dynamics of small terrestrial mammals on various types of restoration in the area of Velká podkrušnohorská spoil heap.

CHARVÁTOVÁ, Pavla January 2011 (has links)
The aim of my thesis was to describe the biodiversity and try to outline the population dynamics of small terrestrial mammals on the Great podkrušnohorská spoil heap. We captured small mammals six times during the 2009 and 2010 seasons. We used the standard capture-mark-release method (CMR) with live traps in quadrates at five sites with different restoration type- wetland, forestry (alderwood and pinewood), agricultural and controlled succession. The observed data were processed in Microsoft Office Excel and by canonical correspondence analysis (CCA) in Canoco for Windows. In 2009 a total of 67 individuals of five small mammals´species were captured: Apodemus flavicollis, Microtus arvalis, M. agrestis, Myodes glareolus and Sorex araneus. The highest biodiversity (3 species) was recorded in wetland restoration. The highest abundance (20 individuals) was recorded in alderwood forestry restoration. In 2010 258 individuals of 7 species were captured: Apodemus flavicollis, A. sylvaticus, Microtus arvalis, M. agrestis, Myodes glareolus, S. araneus and Micromys minutus. As in 2009 the highest abundance was recorded in alderwood forestry restoration(60 individuals) and the highest biodiversity (7 species) was recorded in wetland restoration.
46

Vodní režim rekultivovaných a nerekultivovaných výsypek / Water regime of reclaimed and nonreclaimed heaps

Cejpek, Jiří January 2011 (has links)
Summary: Great Podkrusnohorska spoil heaps in the Sokolov region in Western Bohemia is the largest spoil heaps in the Czech Republic, which was pour million tonnes of overburden soil surface mining of brown coal. The thesis is setting on the basic characteristics of the water regime and water balance of spoil heap soil and thus follows a series of previous works dealing with the comparative development of the reclaimed and unreclaimed area. The areas are long-term monitoring of soil moisture using a dielectric soil moisture meter total water regime was monitored by subsurface with gravitation lyzimeter, runoff and throughfall rainfall. Older unreclaimed plots as well as reclaimed plots have higher porosity, water field capacity and moistre than young sites, however there are limited by water deficiency in similatr way as young sites due to increase in wilting point. Keywords: Spoil heaps, Recultivation, Soil humidity, Water supply, Water balance
47

Faktory ovlivňující šíření buku lesního (Fagus sylvatica) na výsypce / Factors influencing the distribution of European Beech (Fagus silvatica) on the post mining spoil heap

Vobořilová, Veronika January 2011 (has links)
In this thesis the influence of existing vegetation, the distance from the north border of the spoil heap, animal grazing, terrain bumpiness, and soil pH on the distribution and rooting of European Beech (Fagus sylvatica) at spoil heap Velká podkrušnohorská výsypka (50ř14'09 N, 12ř39'05 E) was examined. To accomplish this, beech seedlings within chosen areas overgrown by spontaneous succession or alder restoration were mapped using GPS. A rooting position on the wave-like terrain was recorded for a proportion of the total number of seedlings. Soil pH was also measured on the wave-like terrain. The majority of seedlings (183) were found at the succession sites; only one seedling was found in the alder restoration site. The GLM analysis proved significantly more seedlings in succession sites compared to alder restoration sites (p = 0.0169) and the negative dependence on distance from the north border of the heap (p < 0.0001). Within the wave-like terrain, 46% of seedlings were growing on the north slopes. In 2009, small seedlings were planted into the fresh restoration site and the adjacent succession site, in both cases inside the fencing and outside of it. The seedlings were growing significantly better in the succession site compared to the restoration site, and they were growing better inside the...
48

A study of the diagenesis of the overburden between the Badger and School Coal Seams, Dave Johnston Coal Field, Converse County, Wyoming

Jaffer, Rebecca K. 01 January 1983 (has links)
Low pH zones in portions of the overburden at the Dave Johnston Coal Field, Converse County, Wyoming are the subject of this study. The low pH zones are restricted to limonite stained sandstones which grade downdip into normal pH gray sandstones. Changes in color, clay mineralogy, cementation and feldspar surface textures are noted between the two sandstone units. These changes appear to be the result of post depositional alteration that was responsible for oxidation of pyrite and chlorite, dissoluion of calcite, and the etching of feldspar grains. The parameters for the diagenesis fit those of uranium roll front models proposed for the Powder River Basin. The alteration appears responsible for the low pH values reported in the yellow sandstone. Research by the North Dakota Geological Survey on similar problems associated with lignite mines in North Dakota suggests reclamation procedures for dealing with these potentially hazardous overburden spoils.
49

Sukcese mravenců na výsypkách / Ant succession in post mining sites

Hovorková, Marie January 2021 (has links)
Succession is often studied by using a chronosequence. When using a chronosequence we study a set of sites with different ages at the same time and by comparing them we conclude what kind of changes occurred during time (space for time substitution). Only a few studies however compare how results obtained by using a chronosequence differ from those obtained by long-term studies. In my theses I repeated a study that investigated succession of ant communities on brown coal mining spoil dumps in Sokolov district after 19 years. There are chronosequences of two types of sites (spontaneous succession and recultivation) in Sokolov coal mining district. By repeating the original study I could compare changes that occurred du- ring time with changes along a chronosequnce. Relationship between occurrence of ant groups with different ecological requirements and age of site was also investigated. RDA model and variation partitioning were used to find out statistical significance between sites and their age. An increase in number of species was recorded on the spoil dumps. 22 ant species were found in the year 2020, from which 5 species were new on the dumps. All the new species are specialists, two of them are dendrophilous. A statistically significant increase in abundance of forest species with site age was...
50

GEOCHEMICAL FACTORS AFFECTING THE TRANSPORT AND REACTIVITY OF METALS AND PYRITE COLLOIDS IN COAL MINE SPOILS

Chowdhury, Md Abu Raihan 01 August 2022 (has links)
No description available.

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