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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.
31

Secondary metabolite profiles of Lippia Scaberrima sond. from gold mine tailings

Lepule, Sello Presly. January 2011 (has links)
M. Tech. Chemistry.
32

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.
33

Soft-sediment benthos of Aramoana and Blueskin Bay (Otago, New Zealand) and effects of dredge-spoil disposal

Paavo, Brian Lee, n/a January 2007 (has links)
Studies were conducted to broadly describe and understand the sediment benthos of a shallow-water coastal area (Aramoana Beach - Heyward Point - Blueskin Bay) near the entrance to Otago Harbour, a system largely representative for southeastern New Zealand. Benthic assemblages were examined in relation to gradients of wave exposure and disturbance, sediment type and bathymetry, and dredge-spoil disposal. Sediment and macrofaunal surveys in autumn and spring 2003 found little change in sediment texture gradients from historical studies and a lack of vertical stratification. Macrobenthic samples from spring produced significantly higher abundances of three numerically dominant phyla (Arthropoda, Annelida, and Mollusca) and higher taxon richness compared to autumn. Within water depths of 6-30 m, abundance, richness, and diversity increased with depth. Multivariate analyses identified similar assemblages among deeper sites, despite sediment textural differences, whereas distinct assemblages were found in the shallow portions of the three areas. Meiofaunal abundance patterns did not reflect those of macrofauna, possibly indicating greater vertical penetration of sediments in these hydrodynamic environments. Several new kinorhynch taxa were found. In a field manipulation, part of the Aramoana dredge-spoil dumpground was protected from spoil disposal for an extended period followed by experimental dumping of sandy and muddy spoil. Macrofaunal samples were collected before dumping and at nine sites < 119 d after disposal. Water velocities at the sediment-water interface were compared to a local sediment disturbance model. Dumpground samples were depauperate in individuals and taxa compared to an area protected from dumping for > 180 d. A drop in abundance and a dissimilar community coincided with muddy spoil, but fine sediments were dispersed within 26 d and macrofaunal assemblages recovered to the pre-existing state. Sandy spoil, while not altering native sediment textures, had a more prolonged impact due to transplantation of macrofauna from the dredged area that persisted for < 41 d after disposal. Side-scan sonar mapping indicated that the disposal footprint model used approximated the extent of sandy spoil impacts well, while local conditions spread muddy sediments beyond the initial impact site. A novel sediment profile imaging device was constructed that has many advantages over existing devices for spoil mound studies and habitat mapping: it is smaller, can be manually deployed from small boats, is cheaper, and can be modified to work in almost any soft sediment. Studies of one dominant taxon, the gastropod Zethalia zelandica, showed it was better able to survive sand burial than mud burial, did not vary in overall activity through a range of 5-14� C, and contributed a large proportion of biomass of its community. The spoil disposal strategy used does not appear as environmentally neutral as originally thought. Only muds are effectively dispersed whereas coarser sediments accumulate, affecting physical and biological benthic processes of a wider area. Two mitigation strategies were evaluated using a heuristic model. Reducing the disposal area and spreading mud disposal events over a longer time span may be an effective interim strategy. Overall, the studies will help guide management of the area.
34

Water-harvesting on arid coal mine soil for vegetable and fruit production

Powelson, David. January 1982 (has links) (PDF)
Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1982. / Includes bibliographical references (leaves 72-77).
35

Étude de mise en valeur des rejets de carbonate-apatite de la mine Niobec dans le but d'une utilisation comme engrais en agriculture /

Savard, Jean Y. January 1981 (has links)
Mémoire (M.Sc.A)- Université du Québec à Chicoutimi, 1981. / "Mémoire présenté en vue de l'obtention d'un diplôme de M.Sc.A. (géologie)" CaQCU Document électronique également accessible en format PDF. CaQCU
36

Vliv způsobu a stáří rekultivace ploch po povrchové těžbě na biodiverzitu drobných zemních savců / The influence of the type and age of post-mining areas restoration on biodiversity of small terrestrial mammals.

MIKLAS, Bořek January 2011 (has links)
The aim of the study was to compare different types and ages of restoration from the small mammal biodiversity perspective. In 2004, three linear and two quadratic trappings of small terrestrial mammals were performed at the Velká podkrušnohorská spoil heap. Linear trappings were repeated in 2009 and quadratic were repeated in 2010. In 2004, 174 small mammals in the linear trappings and 199 small mammals in the quadratic trappings were captured. We found, that the wetland localities were the richest in small mammal diversity, the forestry restored areas were second ones, and the agriculturally restored areas were the poorest ones. During the repeated trappings, 45 small mammals in linear trappings and 64 small mammals in quadratic trappings were captured. A decrease of both abundance and biodiversity was recorded in the both types of trappings. The highest biodiversity was on wetland and forestry restored areas. The lowest biodiversity was on agriculturally restored areas. The highest abundance was on forestry sites during the linear trappings. The wetland areas were second ones and the lowest abundance was on agriculturally restored areas. Value of abundance in quadratic trappings was almost the same in wetland and forest habitats, whilst the abundance of agricultural areas was significantly lower. The results show the importance of wetland habitats, which are very important part of restoration and have a positive impact on the overall biodiversity in the landscape.
37

Reakce půdních vířníků (Rotifera) na chemický stres v substrátech hnědouhelné výsypky / Reaction of Soil Rotifers on Chemical Stress in Substrates of Spoil Heaps

BIZOS, Jiří January 2011 (has links)
Abundance and species composition of soil rotifer communities was investigated in two seasons and six sites on dumps in the Sokolov mining area (Czech Republic). Every site was split into three plots, which differed in toxicity for vegetation and chemical composition of spoil material. The ability of soil rotifers to live in environment of spoil materials and the effect of pollution were studied in field conditions. According to results, abundance and species composition did not correspond to chemical environmental characteristics. Species composition of rotifer communities was affected by environmental variables such as vegetation, more likely than direct effect of chemical composition of spoil material.
38

Toxicita výsypkových substrátů a možnosti jejího zmírnění / Spoil heap toxicity and possibilities for remediation

Venclovská, Lenka January 2011 (has links)
The content of this diploma thesis is to verify of possibilities for remediation spoil heap toxicity in Sokolov area, by the help of creating biological crusts. The main question of this work is the possibility of using algae to create biological crust on toxical substrates, which could improve the properties of substrates and contribute to the acceleration of succession. The correctness of this theory was tested using two tests on toxic soils in spoil heaps near Sokolov. In the first test (laboratory test) have been chosen two of the soils and the higher plants, in most cases, even did not germinate. That is why we decided to verify the second option to create biological crust in these phytotoxic soils. Therefore we applied selected kinds of algae in the field, some areas were liming, and the field has been monitoring and sampling during next three years. The results show that the application of dolomitic limestone does not affect progress of biological crusts. The result of the fluorescent microscopy clearly shows, that Klebsormidium algae was the only one of the tested algae, which survived and progressed compact visible crusts.
39

Engineering Properties, and Slope Stability and Settlement Analysis Related to Phosphate Mine Spoil Dumps in Southeastern Idaho

Riker, Richard Ellsworth 01 May 1978 (has links)
The engineering properties of waste spoil from phosphate mines in Southeastern Idaho were determined through field and laboratory testing. The testing included compaction tests, grain size analysis, powder x-ray defraction tests, permeability tests, compression tests, triaxial and direct shear strength tests, and nutrient analyses. Based on these tests, the slope stability and settlement characteristics of phosphate spoil dumps were investigated. The study showed that the foundation is an important component of the stability of a spoil dump. Hypothetical examples were used to illustrate possible modes of foundation failures. Such failures might occur when weak foundation soils exist or when there is a lack of embankment-foundation preparation prior to the disposal of waste material. When considering failures through only the middle waste shale embankment material, the study showed that dumps constructed by end-dumping the spoil material over angle of repose embankments or by scraper filling the material in horizontal lifts will be adequately safe against slope failure if: o Embankment slopes are graded to 21/2 horizontal to 1 vertical or flatter. o Proper precautions are taken to prevent the build-up of a phreatic surface near the top of the embankment. The study also showed that post construction settlement in spoil dumps can be attributed to: o A slow continuing settlement which is linear with the log of time. o Saturation collapse settlement which occurs with increases in the moisture contents. Post construction settlement in spoil dumps is caused principally by increases in the moisture content in layers of middle waste shales and soft cherts. A rationale method for predicting magnitudes of post construction settlement in spoil dumps was also developed as part of this study.
40

The Effect of Four Mine Spoil Treatments on the Seedling Water Relations of Two Plant Species

Van Kekerix, Lorraine K. 01 May 1977 (has links)
Surface mines in mountainous areas cause environmental deterioration at lower elevations in the watershed. The most successful long term solution to the downstream problem is revegetation. However, mine spoils are low in essential plant nutrients, have low water holding capacity, and are often acidic. These factors limit plant colonization. Plants must also be adapted to the environmental conditions of high elevations. At the McLaren Mine, }1ontana, at 2800 m, it was observed that seedlings on revegetation plots were desiccated, indicating possible water deficits. Field and growth chamber studies were carried out to determine the effects of some spoil ameliorating treatments on leaf water potentials, leaf pressure potentials and seedling development and mortality. Poa alpina L. and Alopecurus pratensis L., the two plant species seeded are successful revegetation species in the area. The four treatments were: 1) a control group with no spoil treatment, 2) peatmoss incorporated into the spoils, 3) a surface mulch of jute net, and 4) peatmoss-plus-jute net. Results showed a decrease in water stress experienced by plants on plots with spoil ameliorating treatments. The jute net, or peatmoss-plus-jute net treatments were the most effective in reducing water stress. Leaf pressure potential data were extremely variable, making it difficult to determine trends. In the field seedling mortality was reduced on plots with jute net or peatmoss--plus-jute net. No trends were apparent in the growth chamber study. In both studies seedlings were larger with jute net or peatmoss-plus-jute net treatments.

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