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1
Read, Tamara. « Spotted gum forest re-establishment on coal mined land : influence of seed sources, substrate and mulch / ». [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16850.pdf.
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Regula, Victoria A. « Recolonization of arthropod and nematode assemblages in reclaimed mineland soils of Wyoming ». Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1445041671&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Rutter, Anthony Paul. « A study of factors affecting the regeneration of mineral exploration sites in the semi-arid and arid areas of South Western South Australia / ». Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09ENV/09envr982.pdf.
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Emerson, Paul. « Growth and survival of eleven planted tree species on a reclaimed surface mine in West Virginia ». Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5582.
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Thesis (M.S.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains xi, 84 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 77-84).
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Balcerzak, Melissa J. « Raptor abundance and diversity and red-shouldered hawk (Buteo lineatus) habitat characteristics on reclaimed mountaintop mines in southern West Virginia ». Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2234.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains xii, 73 p. : ill. (some col.), map (some col.). Vita. Includes abstract. Includes bibliographical references.
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Sanidad, Wilfredo B. « Comparative studies of the water use characteristics of native tree species growing on a rehabilitated mine site in the wet - dry sub - tropics of Queensland / ». St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17423.pdf.
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Kopittke, Gillian Ruth. « Long-term ecosystem development on an open-cut coal mine in central Queensland / ». [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19408.pdf.
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Kurnik, Betsy S. « Diversity of ectomycorrhizal fungi on two reclaimed surface mines differing in soil properties ». Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1698.
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Thesis (M.S.)--West Virginia University, 2000.Title from document title page. Document formatted into pages; contains viii, 72 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 61-64).
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Kazar, Sheila A. « Surface mines as landscape features contrasting microclimate and forest composition among open, edge, and interior / ». Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=3149.
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Thesis (M.A.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains vii, 56 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 50-55).
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Khalifa, Aly Ashraf Mohammed. « MINErosion 4 : A user-friendly catchment/landscape erosion prediction model for post mining sites in Central Queensland ». Thesis, Griffith University, 2010. http://hdl.handle.net/10072/366197.
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Soil erosion from post mining landscapes subjected to significant rainstorm events is believed to have adverse effects on the surrounding environment, as well as the mining processes. The research project reported in this thesis was encouraged by the fact that, to the best of the author’s knowledge, there is a lack of catchment/landscape scale erosion/deposition model, to deal with the special conditions of post-mining rehabilitation sites. Previous research has produced the hillslope erosion model MINErosion 3.01 which was useful to determine the parameters (slope gradient, length and vegetation cover) required to design a postmining landscape that meets the criteria of acceptable erosion rates (<40 t/ha/y). However, MINErosion 3.01 was not suitable to determine the erosion rates from whole catchments or whole of mine landscapes and a model is needed to provide the environmental officers with a tool to allow them to manage the whole of mine landscape, specifically in relation to offsite and onsite discharges of water and sediment. MINErosion 3.01 was found to be a suitable for upscaling to produce a new user-friendly catchment scale model named MINErosion 4. As an initial stage, MINErosion 3.01 was revised to fix some of its errors and add some new features and a new version MINErosion 3.1 was developed and validated against plot data from a previous project (Postmining Landscape Parameters for Erosion and Water Quality Control, 1992-1998). The agreement between predicted (Y1) and measured (X1) annual average soil loss is good with a regression equation of Y1 = 0.8 X1 + 0.005 and an R2 = 0.70; while predicted (Y2) and measured (X2) rainstorm erosion events have a regression of Y2 = 0.867 X2 with an R2 of 0.68. As the new model should be a spatial distribution model, the variability of media properties of Central Queensland coal mines need to be determined. Ninety three soil and spoil samples were collected from six selected coalmines. They were analyzed and represented in both MINErosion 4 model database and as a standalone database file for Central Queensland coalmines media properties. These properties were used to derive the rill and interrill erodibilities of soil and spoil. These values are generally in agreement with the values in the embedded MINErosion 3.1 database as determined by Sheridan (2001). This work shows large variability in soil and spoil erodibilities which should result in large variability in erosion rates across a minesite. A knowledge of the hotspots in advance will assist the mine to manage and allocate suitable resources across the postmining landscape.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
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Stark, Christina Antonia Ronquillo. « Recovery of vegetation on acid drainage impacted arid soils / ». abstract and full text PDF (free order & ; download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1437665.
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Thesis (M.S.)--University of Nevada, Reno, 2006."(August 2006)." Includes bibliographical references (leaves 85-87). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2006]. 1 microfilm reel ; 35 mm.
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Gillespie, Melina Jane. « Establishment success of native understorey species on coal mine rehabilitation areas in the Hunter Valley, New South Wales / ». St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17522.pdf.
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Wick, Abbey Foster. « Soil aggregate and organic matter dynamics in reclaimed mineland soils ». Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1400961671&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Alden, Matthew G. « Remote sensing techniques for monitoring coal surface mining and reclamation in the Power River Basin ». Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1257279388.
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Anderson, Jonathan D. « Impacts of amending bauxite residue sands with residue fines for the establishment of vegetation on residue disposal areas / ». Murdoch University Digital Theses Program, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.
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Ndeinoma, Albertina. « Mycorrhiza re-establishment on post mined rehabilitated areas of the Brand se Baai Succulent Karoo vegetation / ». Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1133.
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Hardiputra, Bingah Astuti. « Properties of rehabilitated coalmine soils at Collie ». University of Western Australia. Soil Science and Plant Nutrition Discipline Group, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0041.
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[Truncated abstract] Many soil properties are involved in supporting the growth of plants and in limiting soil degradation. The present study was carried out to provide a basis for minimising environmental impact by providing a firm understanding of the soil properties that affect plant growth for soils developed from mining waste from the Wesfarmers Premier coalmine at Collie. The purpose of this study was to provide an understanding of the soil materials and to identify the potential interactions between soil properties and plants for soils developed on coalmine materials at the Premier mine, Collie. This research was to identify the nature of the manmade soils so as to determine if soil forming processes are active, to determine soil acidity including pH buffering capacity and the lime requirement of soils, to measure water retention characteristics and soil available water for plant growth, to relate soil properties to possible effects on plant growth, and to identify management strategies to improve soil conditions and overcome plant growth constraints. Seventy-seven manmade horizons from pits in 18 constructed soils, ranging from 9 to 21-years old, were analyzed throughout this study. These samples are classified based on soil depth, layer (topsoil and subsoil), and age of soil since rehabilitation. The methods for doing most of the analyses follow the Australian Soil and Land Survey handbook by Rayment and Higginson (1992). The results are presented quantitatively and soil properties are compared to provide information on pedogenic processes, the extent of soil development, the ability of the soils to resist degradation and to provide an indication of soil parent materials
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Prananto, Agnes Kristina. « The use of remotely sensed data to analyse spatial and temporal trends in vegetation patchiness within rehabilitated bauxite mines in the Darling Range, W.A. / ». Connect to this title, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0012.
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Wei, Honghong. « Impact of mine land reforestation and revegetation on water quality in a mid-Appalachian watershed a stream monitoring study / ». Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5831.
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Thesis (M.S.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains viii, 92 p. : ill., maps (some col.). Includes abstract. Includes bibliographical references (p. 56-62).
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Herendeen, Robert V. « Two-year Performance of Hybrid and Pure American Chestnut Castanea Dentata (Fagaceae) Seedlings and Benefit of Pisolithus Tinctorius (Sclerodermataceae) on Eastern Ohio Mine Spoil ». Ohio : Ohio University, 2007. http://www.ohiolink.edu/etd/view.cgi?ohiou1174414428.
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Mengler, Faron. « Gully erosion on rehabilitated bauxite mines ». University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0176.
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[Truncated abstract] Landforms rehabilitated after bauxite mining can be vulnerable to soil loss by water erosion processes. On most rehabilitated sites, management controls such as deep ripping, contour mounding and landscaped sub-catchments limit erosion. Despite these measures, severe gully erosion that is anecdotally associated with steep slopes can damage rehabilitated areas and affect downstream drinking water resources. A review of erosion dynamics reveals that gullies develop episodically and in a non-linear manner. They often initiated as a near surface process and are influenced by natural climatic drivers. Despite this, local site characteristics including soil and landform can predispose an area to gully erosion. Moreover, erosion models, becoming more-widely utilized within the mining industry, may provide useful tools with which to measure, analyse, and manage gully erosion. One of these models, SIBERIA was tested to determine its suitability for application a tool to help manage erosion risk. We first surveyed 26 eroding and erosion-prone rehabilitated hillslopes to determine the common form and setting for gully erosion on these rehabilitated bauxite mines. A conceptual model was developed to include and explore the interplay between the common causes of the gullies surveyed. The conceptual model accounts for slope steepness but suggests that additionally, certain triggers and threshold effects operating under different site conditions are as influential (or even more influential) than slope steepness as determinants of gully erosion occurrence and severity. ... Soil properties and soil erodibility had some subtle influence on landform stability and erosion risk. The most-erodible media occurred where either: mine floor material was mixed with topsoil/ overburden; and/or the topsoil/overburden layer was thin or its coverage is patchy resulting in slaking subsoil, hardsetting soil and surface crusts. When erodible surface media were combined with steeper (>8[degrees]) or longer (>50 m) slopes or with any major erosion trigger, rill and gully development was greatly intensified. The SIBERIA simulation model was calibrated and its simulated outputs were compared to known locations of gully erosion on a steep, rehabilitated pit from the Willowdale mine. At a resolution of one metre, SIBERIA was able to simulate the approximate dimensions of gullies. However, SIBERIA could not simulate the exact location of individual gully headcuts. Additionally, SIBERA was able to simulate the effect of different microtopographic surface treatments but this was only achieved by increasing the grid resolution to 25 cm and reducing the size of the area simulated due to model constraints. Locations of gully headcuts were overlain onto a grid-based, Digital Elevation Model (DEM) using a Geographic Information System (GIS). The spatial distribution of gully headcut locations was compared to DEM derivatives such as slope and flow accumulation. Positive, and predictive relationships allow between the steepness of the slope of the pre-mining landform and the cell count of the area contributing to flow (catchment), as determined by GIS, may allow a mine scale indication of erosion risk using simple GIS desktop analysis.
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Gouws, Johan. « The cost benefit analysis of reclamation strategies used in surface coal mining to ensure sustainable post-mining land use ». Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97326.
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Thesis (MBA)--Stellenbosch University, 2015.ENGLISH ABSTRACT: In this study, a cost benefit analysis was done to determine the best possible methods for postmining reclamation. A comparison was made between a conventional method with additional organic material added to the soil and a Backgrounding method where cattle are reared on the land. The best method, according to the financial model that was built, was the method of Backgrounding cattle on the rehabilitated land. The main reason for this outcome may be due to the fact that the meat that is produced is a high value product. It might not be practically applicable to mines at this stage, but the calculation provides an insight into the possibilities that reclaimed mine land holds for the agricultural industry.
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Van, Eeden Joseph Deon. « Cost-effective, post-mining environmental restoration of an open-cast phosphate mine at Langebaanweg, South Africa ». Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1003801.
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Approaching the ecological rehabilitation of an open-cast phosphate mine in the West Coast of South Africa during the post-operational phase presented some challenges. The area was extensively modified during the mining operations. Soils from different layers were mixed with topsoil being covered by subsoil, overburden dumps and tailing dams being constructed resulting in extensive cross-zoned soils. Large areas of subsoil areas were exposed on the mine floor with localized and small scale salinity being evident. The modified topography as well as the complex new surface material posed a challenge in terms of identifying suitable local species that could be used to rehabilitate the post-mining environment. The mine area was heavily infested with woody alien invasive plants, such as Acacia cyclops, established in an attempt to reduce the dust and little natural vegetation cover was present. In the arid west coast environment, the four-month-long winter growing season is followed by hot and windy dry summers (Chapter 2) presenting a challenge reestablishing local vegetation in modified soils. Moreover, little was known about the local vegetation in terms of their propagation and use in stabilization techniques as an alternative to exotic vegetation such as the A. cyclops, which had been more often used in revegetation projects. A study was conducted to determine the most efficient and cost-effective methods of vegetative rehabilitation of the Chemfos site (Chapter 1). A review of the literature available at the time as well as approaches that were successfully implemented in other Western Cape rehabilitation projects such as the Du Toitskloof Pass and the Sishen–Saldanha railway line (Chapter 3), were considered. Previous studies on the west coast dunes at Blaauwberg had shown using Marram grass as a dune stabilizer was most successful. Marram grass was tested in trials alongside local grasses, such as Chaetobromus dregeanus and Ehrharta villosa, that showed potential but had not been formally evaluated. The environmental context of Chemfos (Chapter 2) as well as the Conceptual Rehabilitation Plan that considered the modified environment, soils and closure objectives of the mine, were reviewed to determine the most pressing rehabilitationrelated questions that required answers. This led to the final experimental design that was implemented mid-winter in 1996 (Chapter 5). The trials were implemented in the areas perceived to be the most difficult to rehabilitate, namely the mobile sands in the tailings dam and the exposed subsoil or mine floor areas. The use of brushwood together with specific plants and seeds appropriate for the use in either sandy soil or subsoil were evaluated in a variety of combinations and application densities to determine the most effective treatment combination at the minimum effective density. The best initial cover of the tailings dam were recorded in the Ammophila arenaria trials but the use of the local grass species Ehrharta villosa, performed better from year two onwards and was much cheaper to establish. On the subsoil, the trials where a cover of topsoil was used performed better than the combination trials. This indicated that topsoil placement on post-operational phase shaped subsoils during the mining operation to be the most desirable treatment. Initial results of the trials were used as a basis for developing the rehabilitation techniques that were rolled out across the Chemfos landscape. The approaches were refined as indications of trial responses became evident. Lessons learned were incorporated in the adaptive management approach that was followed and the rehabilitation techniques (Chapter 6) were continually re-evaluated and adjusted. This resulted in a significant step towards achieving the overall research objective of finding cost-effective approaches to rehabilitation. Components such as refinement of the seed collection and processing techniques (Chapter 7) where the post-harvest processing cost was significantly reduced by introducing specially designed drying racks. Processing techniques were adjusted to suit the different species, and a variety of mechanical processing options were explored. The scale of the Chemfos project led to the development of new techniques of manufacturing a smoke-derived germination stimulant (Chapter 8) since commercial availability of these products was very limited. The development of FireGrow assisted in the overall aim of reducing cost by increasing germination of seed in the rehabilitation sites using a very cost-effective smoke concentrate. Socio-economical aspects were considered during the implementation as well as the post-closure phases of the rehabilitation and BHPBilliton invested through the agency of the SAMANCOR Trust. This led to the development of livelihoods of the staff that remained in the area and that lived in the mine village. The demography of the population has changed over time in the Green Village as well as the skills that the inhabitants have developed. Thus, the new economic opportunities that were pursued have brought a new lease on life beyond the lifespan of the mine (Chapter 9) once the closure certificate had been issued.
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Mahood, Kirsten. « Strip mining rehabilitation by translocation in arid coastal Namaqualand, South Africa ». Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53603.
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Degree of Master of Forestry (Conservation Ecology)Thesis (MSc)--Stellenbosch University, 2003.
Full text to be digitised and attached to bibliographic record.
ENGLISH ABSTRACT: This study investigates the use of top-soiling, irrigation and translocating indigenous plants to facilitate the cost-effective return of a mined landscape to its former land-use (small stock farming) in an arid winter rainfall Succulent Karoo shrub land biome on the West Coast of South Africa. Effects of topsoil stockpiling and subsoil mineral concentration on soil fertility and chemistry were investigated, as soils are likely to determine rates of vegetation recovery on post-mined areas. Results of a radish bioassay show that stockpiling topsoil and mineral concentration subsoil decreased soil fertility. Mineral concentration decreased phosphorus, potassium, calcium, magnesium, carbon and nitrogen levels significantly relative to other soil treatments. Sodium in freshly deposited tailings was at potentially toxic levels and significantly higher than for all other soil treatments. Spreading of stockpiled topsoil over tailings may ameliorate harsh conditions created by mineral separation. Translocation of plants from pre-mined to post-mined areas was carried out on a trial basis in an effort to facilitate the return of natural vegetation and processes to strip-mined landscapes. Five local indigenous plant species: Asparagus spp., Ruschia versicolor, Othonna cylindrica, Lampranthus suavissimus and Zygophyllum morgsana were planted into multi-species clumps in a replicated experiment. Variables examined in the translocation trial included the effects of plant origin, soil treatment and/or irrigation on plant survival and establishment. The proportion of O. cylindrica transplants surviving for 15 months was greater than for other species. Whole plants survived better than salvaged plants, and Asparagus spp., R. versicolor, L. suavissimus and Z. morgsana survived better on stockpiled topsoil spread over tailings than on tailings alone. Irrigation had no consistent effect across species and treatment replicates. Salvaged-plant clumps were significantly larger than whole-plant clumps at planting, however, this effect was not observed after 12 months, indicating that whole-plant clumps grew faster than salvaged-plant clumps. The evergreen, leaf succulent shrubs O. cylindrica, L. suavissimus and R. versicolor appeared to be most suitable for large-scale translocation at Namakwa Sands. The return of biodiversity and changes in soil quality 15 months after translocation trials began were compared for combinations of top-soiling, irrigation, plant translocation and unmodified tailings. Irrigation may reduce biodiversity and seedling densities. Over a 15-month period following back filling and topsoil spreading, sodium, potassium and calcium appeared to return to levels observed for undisturbed soils. Magnesium remains at levels lower than in pre-mined soil conditions. Soil conditions may be more conducive to plant establishment and rehabilitation after back-filling of tailings and topsoil spreading. Electrical resistance increased over time indicating a reduction of free salts and salinity on rehabilitation sites. Phosphorus did not return to pre-disturbance levels, and carbon remained below pre-mining levels for at least 15 months after rehabilitation began, remaining a potential limiting factor in rehabilitation. Each rehabilitation technique that a mine employs has costs and benefits, and it is increasingly important that insights from ecology and economics are coupled if restoration efforts are going to succeed. A review of valuation systems indicates that Discounted Cash Flow Techniques (DCF) are suitable for valuation of rehabilitation operations.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die gebruik van bogrond, besproeiing en die oorplanting van inheemse plante om die koste-effektiewe rehabilitasie van 'n stroopmynlandskap in die droë, winter reënval streek, Vetplant Karoo aan die Weskus van Suid-Afrika, wat vroeër gebruik is vir kleinvee boerdery, te bespoedig Die uitwerking van bogrondopberging en minerale konsentrasie op vrugbaarheid en chemise komposisie van grond is ondersoek, aangesien dié gronde gewoonlik die herstelspoed van plantegroei op 'n ou myn terein bepaal. Uitslae van radys proewe toon dat berging van bogrond en minerale konsentrasie van die onderliggende grond vrugbaarheid van grond laat afneem. Mynaktiwiteite en die minerale konsentrasie lei tot 'n betekenisvolle verlies aan fosfaat, kalium, kalsium, magnesium, koolstof en stikstof as die geval met ander bedrywighede. Die vlak van natrium in oorgeblywende sand na die minerale ekstraksie is hoogs giftig en is veel hoër as na ander bedrywighede. Die toediening van bogrond oor die oorblywende sand verbeter die toestand wat deur die skeiding van minerale veroorsaak is. Oorplasing van plante vanaf ongemynde na rehabilitasie gebiede is op proefbasis uitgevoer in 'n poging om die terugkeer van natuurlike plantegroei by die strookmyn te bespoedig. Vyf plaaslike inheemse plantspesies: Asparagus spp., Ruschia versicolor, Othonna cylindrical, Lampranthus suavissimus en Zygophyllum morgsana is in multi-spesie groepe geplant. Veranderlikes getoets tydens hierdie proef sluit in plantoorsprong, grond behandeling, en/of besproeiing, op die oorlewing en vestiging van plante. 'n Groter proporsie O. cylindrical as enige ander spesie het na 15 maande oorleef. Heel plante het beter oorleef as beskadigde plante. Asparagus spp., R. versicolor, L. suavissimus en Z. morgsana het beter oorleef op gebergde bogrond oor oorblywende sand as op oorblywende sand self. Besproeiing het nie 'n volgehoue uitwerking gehad op spesies of op herhaalde replisering nie. Beskadigde plantgroepe was groter as heelplant groepe toe hulle geplant is maar na 12 maande is opgemerk dat die heel-plante vinniger gegroei het. Die immergroen vetplante, 0. cylindrical, L. suavissimus en R. versicolor blyk die mees geskik vir grootskaalse oorplanting by Namakwa Sands. Herstel van biodiversiteit en veranderings in grondeienskappe 15 maande na proewe begin het, is vergelyk m.b.t. die toediening van bogrond, besproeiing, oorplanting en onbehandelde oorblywende sand. Besproeiing kan biodiversiteit en digtheid van saailinge verminder. Vyvtien maande na opvulling en die toediening van bogrond, het kalium, natrium en kalsium teruggekeer na vlakke in onversteurde grond. Magnesium vlakke was nog altyd laer as dié voordat mynaktiwiteite aangevang is. Terugplasing van sand en toediening van bogrond mag die vestiging en rehabilitasie van plante bespoedig. Weerstand vermeerder met tyd wat 'n verlaaging in vry soute en soutagtigheid in die grond wat gebruik is vir rehabilitasie aantoon. Fosfor het nie teruggekeer tot vlakke van voorheen nie en vlakke van koolstofhet na 15 maande verlaag gebly, en kan die potential tot rehabilitasie belemmer. Elke rehabilitasie tegniek wat die myn gebruik bring kostes sowel as voordele mee. Om restorasie pogings te laat slaag moet insigte vanaf ekologie en ekonomie saam ingespan word. 'n Oorsig van waardasie sisteme toon dat Afslag Kontant Vloei Tegnieke geskik is vir die evaluasie van rehabilitasie programme.
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Mahardhika, Hapsara. « Effectiveness of Soil/Spoil Amendments in Minimising Adverse Impacts of Runoff and Erosion at Coal Mine Rehabilitation Sites in the Bowen Basin Region, Central Queensland ». Thesis, Griffith University, 2012. http://hdl.handle.net/10072/367329.
Texte intégralRésumé :
Effects of vegetation cover on runoff and soil loss reduction at mine rehabilitation sites are well documented. However, the knowledge of soil amendment applications, namely polyacrylamide (PAM) and gypsum, prior to the establishment of vegetation is still very limited. These soil amendment methods have proven to have the ability to improve soil surface stability in agriculture, however, the application of soil amendments to improve the spoil surface at mine rehabilitation sites is still un–trialled and their effectiveness largely unknown.
This study covers 4 topics namely; (1) to analyse the effectiveness of soil amendments towards improving the hydraulic conductivity of the soil and spoil; (2) to determine the effect of soil amendments application on sediment concentration in the runoff and total soil loss generated from the laboratory based soil erosion experiments; (3) to assess WinSEADS model (Soil Erosion and Deposition Simulation – Windows) to predict sediment concentration and total soil loss under a variety of scenarios; (4) to carry out cost assessment of possible field application of soil amendments under several scenarios.
In the small–scale experiments, the application of soil amendments to the soil and spoil was found to be beneficial in increasing the hydraulic conductivity. The results indicate that gypsum is more effective in maintaining a high hydraulic conductivity when compared with PAM. The percentage increase of hydraulic conductivity was found to depend on the soil amendment application rates; and the physical and chemical characteristics of the soil and spoil.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
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Ntshotsho, Phumza. « Carbon sequestration on the subtropical dunes of South Africa a comparison between native regenerating ecosystems and exotic plantations / ». Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-06132006-101405.
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Schmidt, Anel. « Strip-mine rehabilitation in Namaqualand ». Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53068.
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Thesis (MScFor)--Stellenbosch University, 2002.ENGLISH ABSTRACT: Namaqualand has a very unusual diversity of plant life, with many endemic plant species. The fundamental question of this thesis is how this system, damaged by strip-mining activities, can be rehabilitated. The aim was to base the rehabilitation methods on ecological processes. In order to answer this question an overview of the relevant literature was needed in order to identify possible research needs and also to evaluate the work that has been done in the field of strip-mine rehabilitation in arid areas. An understanding of community and ecosystem dynamics would help to establish aims and methods for site-specific rehabilitation. In Namaqualand, South Africa, there is also a need for experimentation to establish which of the many factors is most limiting to long-term ecosystem recovery. It is important to have a good knowledge of the successional processes and disturbance history of the land which needs to be rehabilitated. The vegetation on unmined areas and mined areas of different ages and treatments after mining, were sampled. It was shown that some areas could be expected to show a large degree of recovery in the space of a few years, whilst others would show little or no recovery over a period of decades. It is important to recognise rehabilitation as a gradual process that takes place at different rates in different areas and in different years. The planting of Atriplex nummularia and sowing of Atriplex semibaccata did not facilitate the return of indigenous, perennial species, but rather seem to inhibit their return. In view of the importance of topsoil in terms of the fertility of the soil and the seed bank present in the topsoil, the influence of topsoil removal and stockpiling due to strip-mining activities were tested. The soil fertility was tested by means of radish bioassays and soil laboratory analysis, whilst species diversity and richness were tested with seedling emergence trials. As expected a higher plant species diversity was found on the unmined soils and radishes grew larger on these soils. The topsoil deteriorated in terms of plant species richness, diversity and soil fertility whilst it was stockpiled. Direct replacement of topsoil would ensure a planting medium closer to the pre-disturbance level that could lead to fairly rapid and successful recolonization of the mined area. Successful plant recruitment also depends on the microsites to which seeds are dispersed. The effect that different microsites had on seed germination, seedling growth and survival was tested. It was found that micro catchments always yielded the highest numbers. The establishment and survival of seedlings in the other microsite types (under single shrubs, under clumped shrubs and in the open) varied, depending on the amount of rainfall received in the particular year. Lastly, I experimented with the translocation of three local, indigenous, succulent plant species. These plants were transplanted either in clumps of three together or alone, since I hypothesized that planting them together would facilitate their survival. However, it was found that it depended largely on the morphology of the plant and the amount of rainfall received in a particular year, whether these plants will compete with each other for limiting resources or facilitate each other's survival. The thesis contributes to the understanding of vegetation dynamics in the Succulent Karoo after strip-mining has taken place. Guidelines are provided based on ecological processes, for strip-mine rehabilitation in the Succulent Karoo.
AFRIKAANSE OPSOMMING: Namakwaland is bekend vir sy ongewone diversiteit van plante, met baie endemiese spesies. Die fundamentele vraag wat deur hierdie tesis gevra word is hoe hierdie sisteem, wat beskadig is deur oppervlak mynbou, gerehabiliteer kan word. Die doel is om die rehabilitasie metodes te baseer op ekologiese prosesse. 'n Oorsig van die relevante literatuur was nodig om moontlike areas van verdere navorsing te identifiseer en ook die navorsing wat reeds gedoen is oor rehabilitasie van oppervlak myne in ariede gebiede, te evalueer. 'n Goeie begrip van gemeenskap en ekosisteem dinamika sal help om doelwitte en metodes daar te stel vir die rehabilitasie van spesifieke areas. Dit is ook nodig om in Namakwaland, Suid -Afrika, uit te vind watter van die baie faktore, die lang-termyn herstel van 'n ekosisteem, die meeste verhinder. Dit is baie belangrik om In goeie kennis te hê van die versteurings geskiedenis van die area wat gerehabiliteer moet word, asook die suksessionele prosesse wat werksaam is. Plantegroei van areas wat op verskillende tye gemyn en verskillend behandel is, asook ongemynde areas is ondersoek. Sekere areas het In groot mate van herstel gewys in 'n tydperk van 'n paar jaar, terwyl ander, min of geen hersteloor 'n periode van dekades getoon het nie. Dit is belangrik om rehabilitasie as 'n geleidelike proses te sien, wat teen verskillende tempos plaasvind tydens verskillende jare en in verskillende areas. Daar is bevind dat die plant van Atriplex nummularia asook die saai van Atriplex semibaccata nie die terugkeer van inheemse, meerjarige spesies bevoordeel nie, maar dit eerder inhibeer. Aangesien die bo-grond so belangrik is in terme van die grondvrugbaarheid en ook die saadbank wat teenwoordig is, word die invloed van die verwydering en opberging van die bogrond getoets. Die grondvrugbaarheid was bepaal deur groei-toetse op radyse en laboratorium analise op die grond te doen. Die plant spesie diversiteit en rykheid was bepaal met In saad ontkieming studie. In ooreenstemming met die verwagte uitkoms, was die plant spesie diversiteit hoër op die ongemynde bo-grond en die radyse het groter geword op dieselfde grond. Dit kom voor asof die plant spesie diversiteit en rykheid, asook die grond vrugbaarheid afneem met tyd wat die bo-grond geberg word. Die direkte verspreiding van die bo-grond nadat dit verwyder is, sal In medium vir die plante verseker wat nader is aan die vlak voordat die grond versteur is. Dit sal oak sorg vir redelike vinnige en suksesvolle terugkoms van plante op die gemynde grond. Die suksesvolle vestiging van plante hang ook af van die mikro areas (klein areas in terme van die grootte van 'n saad, wat In eie mikro-klimaat vorm), waarna saad versprei word. Die effek van sulke mikro-gebiede op die ontkieming van saad, die groei van die saailinge en die oorlewing van die saailinge was bepaal. Mikro-water- opvanggebiede het in al drie bogenoemde gevalle die hoogste syfers getoon. Die vestiging en oorlewing van saailinge in die ander mikro-gebiede (die area onder enkel struike, die area onder groepe struike en oop areas) het gevarieer afhangend van die hoeveelheid reënval wat ontvang is in die spesifieke jaar. Laastens, is daar ge-eksperimenteer met die oorplant van drie plaaslike, inheemse, sukkulente spesies. Hierdie plante was alleen geplant of in groepies van drie, bymekaar. Die hipotese was dat huloorlewingskanse beter sal wees as hulle saam geplant word. Dit was egter bevind dat die hoeveelheid reënval in 'n spesifieke jaar en die morfologie van die plant, bepaal of hulle sal kompeteer vir die beperkte bronne en of hulle deur saam te groei huloorlewingskanse sal verhoog. Hierdie tesis dra by tot die verstaan van die plantegroei dinamika in die Sukkulente Karoo nadat oppervlak mynbou plaasgevind het. Riglyne vir die rehabilitasie van oppervlak myne, gebasseer op ekologiese prosesse, word ook voorgestel.
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Bell, Maria Aletta. « Monitoring rehabilitation success using remotely sensed vegetation indices at Navachab Gold Mine, Namibia ». Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97888.
Texte intégralRésumé :
Thesis (MA)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Remote sensing and vegetation indices were evaluated for its usefulness to monitor the success of the rehabilitation programme of the decommissioned tailings storage facility (TSF1) of the Navachab Gold Mine, Karibib, Namibia. The study aimed to objectively illustrate the rehabilitation progression from tailings (baseline) to soil (capping) and vegetation (planted as well as natural). Baseline data sets of 2004 and 2005 were compared with imagery of 2009, 2010 and 2011. All the images were subjected to panchromatic sharpening using the subtractive resolution merge (SRM) method before georegistration. As no recent accurate topographical maps were available of the study area, the May 2010 image was used as a reference image. All other images were georegistered to this image. A number of vegetation indices (VIs) were evaluated. The results showed that the normalised difference vegetation index (NDVI) and the transformed vegetation index (TVI) provided the most promising results. Although the difference vegetation index (DVI) and enhanced vegetation index (EVI) distinguished the vegetation, rock, and soil classes, it was not as successful as the other VIs in classifying the rain water pond. TVI and NDVI were further evaluated for their efficacy in detecting changes. This was done by generating a series of change images and by qualitatively comparing them to false colour images of the same period. Both the NDVI and TVI delivered good results, but it was found that the TVI is more successful when water is present in the images. The research concludes that change analyses based on the TVI is an effective method for monitoring mine rehabilitation programmes.
AFRIKAANSE OPSOMMING: Afstandswaarneming en plantegroei-indekse is ge-evalueer vir die gebruikswaarde daarvan om sukses van die rehabilitasieprogram vir die geslote slykdam of tailings storage facility (TSF1) van die Navachab Goudmyn, Karibib, Namibië vas te stel. Die studie se doelwit was om die progressie in die rehabilitasie van slyk (basislyn) na grond (dekmateriaal) en plantegroei (aangeplant en natuurlik) te illustreer. Basislyndatastelle 2004 en 2005 is vergelyk met 2009, 2010, en 2011 beelde. Al die beelde is panchromaties verskerp deur die subtractive resolution merge (RSM) metode voor georegistrasie uit te voer. Aangesien geen onlangse, akkurate topografiese kaarte van die studiegebied beskikbaar was nie, is die beeld vir Mei 2010 as ‘n verwysingsbeeld gebruik. Al die ander beelde is op die laasgenoemde beeld gegeoregistreer. Die resultate het gewys dat die normalised difference vegetation index (NDVI) en die transformed vegetation index (TVI) die mees belowende resultate lewer. Al het die difference vegetation index (DVI) en enhanced vegetation index (EVI) goed onderskei tussen plantegroeiklasse en grond- en gesteentesklasse was dit nie so suksesvol met die klassifikasie van die reënwaterpoel nie. TVI en NDVI is verder geëvalueer vir effektiwiteit om verandering waar te neem. Dit is gedoen deur ‘n reeks van veranderingsbeelde te skep en dit dan kwalitatief met die valskleur-beelde vir dieselfde tydperk te vergelyk. Beide die NDVI en TVI het goeie resultate gelewer, maar die TVI was meer suksesvol om beelde met water te klassifiseer. Die navorsing lei tot die gevolgtrekking dat veranderingsanalises met die TVI ‘n effektiewe metode vir die monitoring van rehabilitasie programme is.
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Hewitt, Mark S. « Alternative rehabilitation techniques and sustainable outcomes from mining using appropriate environmental management and mine closure planning in an arid region of Western Australia ». Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2007. https://ro.ecu.edu.au/theses/250.
Texte intégralRésumé :
The subject of this thesis is the development of alternative approaches to environmental management and mine closure plans using case examples of the Big Bell/Cue Mining District and as a working example, an area of unconfined washout of historical gold-mine process tailings located in this arid inland region of Western Australia. This is considered appropriate in the light of the social and political thrust for industry to develop simultaneously positive economic, social and environmental outcomes from their activities. The Big Bell mining operation ceased mining in June 2003 and the Mine Closure Plan reflected a classical approach of minimization of public liability and strict compliance with legislative requirements. During the life of the modern mine the approach to rehabilitation was similarly classical in its approach It is intended for this document to inform the mining industry using the case example of the now closed Big Bell Mine as to how greater long-term outcomes may have been achieved for the State and the region for the future. This thesis specifically investigates alternative ways to approach rehabilitation in arid areas of Western Australia using the washout area as an example and trial area. This thesis has approached the issue by addressing the quantification of what has occurred through the gathering of baseline data of the case study area and then by the implementation of a series of relevant trials to identify appropriate eco-functional process-sensitive methods for rehabilitation as an alternative to current industry practice. Trials investigating the use of "retention banks" and "clay/seed balls" and the use of ex-mine milling waste carbon were conducted to investigate relevant possible techniques suitable for arid mine-site waste dump rehabilitation. Data analysis indicated that the main reason for the high level of degradation within the case study area is due to the smothering effect of the fine clayey tails cover and due to acidity of the tailings. A detailed examination of 92 soil samples found water infiltration of tails-washed areas as half that of control areas. Acidity of alluvium has declined from pH 5.2 to 3.8. The acidity has penetrated at depth to hardpan. Trials were commenced to rehabilitate the area using a combination of earthworks (retention banks and· scarification), pH- adjustment (using ex-mill carbon and crushed lime), and the use of native seed pelletised into clay-balls. The introduction of ex-mill carbon was shown to be effective in ameliorating pH in the tails wash area and improving its capacity to regenerate. Considering it is a widely available waste product with the gold mining industry it should be seriously considered in its application for rehabilitation purposes, and specifically in areas affected by severe acidification and desertification particularly by mismanaged tailings with pyrite content. The use of clay balls should also be subjected to further investigation. It is at least equal to the traditional use of raw seed and fertilizer with immediate and abundant rainfall. As this almost never occurs, it should prove to be superior, in delivering higher rates of viability for seed used. The thesis then attempts to integrate this study within the context of the wider issues of environmental management, specifically the best practice of mine closure plans and the adoption of sustainable economic, social and environmental outcomes from mining as an integral part of responsible operational environmental management plans. The thesis argues that the environmental management planning and specifically the Mine Closure Plan should not waste the myriad of opportunities that are the by-product of mining for the long-term sustainable benefit of the wider region. It is argued that if mining companies are serious about sustainability, then they cannot continue with short-term cycles of mining and closure. However to be realistic it will take concerted willingness from all stakeholders to pursue these outcomes. While a given mining operation can offer extensive resources and assets to support this approach the commercial and legislative pressures of core mining activities necessarily mean that mines are in fact encouraged to simply return the environment back to as natural state after operations are complete. Invariably this means hundreds of millions of dollars of infrastructure are levelled and scrapped to avoid all future liability, whilst the potential for sustainable outcomes is essentially ignored. The same Government that enforces the Mining Act and has a State Sustainability Strategy imposes the conditions which create unimaginative classical mine closure plans. Government, industry and the residents of regions must work together to seriously develop sustainable outcomes to mining.
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Prinsloo, H. P. « Alteration of the soil mantle by strip mining in the Namaqualand Strandveld ». Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1168.
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Pasini, Rachael A. « An Evaluation of Flue Gas Desulfurization Gypsum for Abandoned Mine Land Reclamation ». The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250605536.
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Prananto, Agnes Kristina. « The use of remotely sensed data to analyse spatial and temporal trends in vegetation patchiness within rehabilitated bauxite mines in the Darling Range, W.A ». University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0012.
Texte intégralRésumé :
[Truncated abstract] The assessment of rehabilitation success is time consuming and costly for bauxite miners because large areas of land (~550 ha per year) are involved. In some cases, rehabilitation results in patches of bare or sparsely vegetated soil. This study uses remote sensing imagery to evaluate the growth of vegetation in rehabilitated bauxite mines in the Darling Range, W.A. This work has five aims, which are to (1) compare vegetation biomass within rehabilitated areas and nearby native forest; (2) analyse temporal changes in vegetation growth within the selected rehabilitated areas, in particular rehabilitated areas with patches of bare soil; (3) compare vegetation growth pre- and post- mining; (4) identify the best type of remotely sensed data for this particular study area, and (5) develop an index, which can classify the degree of vegetation patchiness within rehabilitated mine sites. This information will enable rehabilitation workers to identify patches in rehabilitated areas that may require further remediation. The study used RADARSAT, nine years of Normalised Difference Vegetation Index (NDVI) maps (extracted from LANDSAT TM multivariate imagery and Quickbird imagery) and aerial photographs to evaluate forty-seven ~1 ha study sites. Image and map analyses were conducted mainly using ESRI’s software ArcGIS 8.3 and ER Mapper 6.4. Ground truthing was carried out to confirm and recognise the causes of bare patches within the rehabilitated mine sites ... The results indicate that differences in rehabilitation management do not affect this index but the extent of bare patches does. Due to the sensitivity of radar imagery to surface roughness, rehabilitated areas cannot be distinguished from the native forest using radar images. A building (crusher) appears to be the same as mature vegetation. Knowledge of the features in an area is therefore crucial when utilising RADARSAT. The beam elevation angle and profile of the RADARSAT image used, made superimposition of radar and optical imageries impossible. Speckle noise in RADARSAT images made it impossible to detect relatively small bare patches. In addition, the many cloud free days in Western Australia make optical imaging possible so that the ability of radar imagery to penetrate cloud is redundant for this type of study.
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Pauw, Marco Johann. « Monitoring ecological rehabilitation on a coastal mineral sands mine in Namaqualand, South Africa ». Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17886.
Texte intégralRésumé :
Thesis (MSc)--Stellenbosch University, 2011.ENGLISH ABSTRACT: The Exxaro Namakwa Sands heavy mineral sands mine at Brand-se-Baai, on the west coast of South Africa, is an important source of income, development and job-creation in the region. However, this comes at a great environmental cost, as strip mining causes large scale destruction of ecosystems through the complete removal of vegetation and topsoil. This is particularly problematic in an environment, such as Namaqualand, where the arid and windy climate, as well as saline and nutrient-poor soils, hamper rehabilitation. These environmental constraints create the need to develop a site-specific rehabilitation program. At Namakwa Sands the objective of rehabilitation is to “rehabilitate and re-vegetate disturbed areas and establish a self-sustaining Strandveld vegetation cover in order to control dust generation, control wind and water erosion, as well as restore land capability. In general, vegetation will be rehabilitated to a minimum grazing standard capable of supporting small stock (sheep) grazing.” In order to achieve this Namakwa Sands conducted rehabilitation experiments with topsoil replacement, seeding of indigenous species and translocation of mature plants. Monitoring is an important part of the rehabilitation process as it allows rehabilitation practitioners to evaluate success and to adapt their management strategies and rehabilitation methods, as well as to evaluate and, if necessary, change their rehabilitation objectives. This study forms part of the monitoring process at Namakwa Sands. It assesses the success of sites that were experimentally rehabilitated in 2001 and a site that was rehabilitated in 2008, using current practice, in order to identify possible management requirements on rehabilitated sites as well as improvements on rehabilitation objectives, methods and monitoring. This study also tests the Landscape Function Analysis (LFA) as rehabilitation monitoring tool by correlating LFA indices with traditional measurements of biophysical variables or their surrogates. Results showed that experimental sites were not successful in returning vegetation cover and plant species richness to the required levels, but did achieve the grazing capacity objective. These sites will need adaptive management to achieve the vegetation cover and plant species richness objectives. The recently rehabilitated site achieved the three-year vegetation cover and plant species richness objectives, as well as the grazing capacity objective, within two years after rehabilitation. Namakwa Sands should therefore continue using the current rehabilitation method. However, rehabilitation should be done in multiple stages in future to decrease the mortality of nursery cuttings and to facilitate the return of late successional species to rehabilitated sites. The sustainability of small stock farming on rangeland with the grazing capacity that is identified as the minimum objective is questionable and this merits further investigation. LFA can be a useful tool to monitor nutrient cycling and soil stability at Namakwa Sands, provided that enough replicates are used. However, LFA cannot be used as is to assess water infiltration at Namakwa Sands, due to assumptions in the calculation of this index that do not hold for the Namaqualand environment. Landscape functioning should be monitored annually to complement vegetation surveys.
AFRIKAANSE OPSOMMING: Die Exxaro Namakwa Sands swaarminerale-sandmyn by Brand-se-Baai, aan die weskus van Suid-Afrika, is ‘n belangrike bron van inkomste, ontwikkeling en werkskepping in die streek. Daar is egter negatiewe omgewingsimpakte aan verbonde, aangesien die strookmyntegniek grootskaalse vernietiging van ekosisteme veroorsaak deur die algehele verwydering van die plantegroei en bogrond. Dit is veral problematies in ‘n omgewing, soos Namakwaland, waar die droë en winderige klimaat, asook die souterige en voedingstof-arme grond, rehabilitasie belemmer. Hierdie beperkings wat deur die omgewing veroorsaak word skep die behoefte om ‘n rehabilitasieprogram te ontwikkel wat spesifiek is tot die terrein. Die doel van rehabilitasie by Namakwa Sands is om te rehabiliteer en herplant op versteurde gebiede en om selfonderhoudende Strandveld plantbedekking te vestig om sodoende stofgenerering te beheer, om wind- en watererosie te beheer, en om grondgebruik-vermoë te herstel. In die algemeen sal plantbedekking gerehabiliteer word tot ‘n minimum weidingskapasiteit wat kleinveeweiding (skaapweiding) kan onderhou. Om dit te bereik het Namakwa Sands rehabilitasie-eksperimente uitgevoer met terugplasing van bogrond, saai van inheemse spesies en oorplanting van volwasse inheemse plante. Monitering is ‘n belangrike deel van die rehabilitasieproses, aangesien dit rehabilitasie-praktisyns in staat stel om sukses te evalueer en om bestuurstrategieë en rehabilitasiemetodes aan te pas, sowel as om rehabilitasiedoelwitte te evalueer en, indien nodig, aan te pas. Hierdie studie vorm deel van die moniteringsproses by Namakwa Sands. Dit assesseer die sukses op persele wat eksperimenteel gerehabiliteer is in 2001 en ‘n perseel wat in 2008 gerehabiliteer is, volgens die huidige praktyk, om moontlike bestuursbehoeftes op gerehabiliteerde persele en verbeteringe aan rehabilitasiedoelwitte, -metodes en –monitering te identifiseer. Hierdie studie toets ook die geskiktheid van die Landscape Function Analysis (LFA) as ‘n rehabilitasie-moniteringsinstrument deur LFA-indekse met tradisionele metings van biofisiese veranderlikes of hul surrogate te korreleer. Resultate dui daarop dat eksperimentele persele nie suksesvol was om plantbedekking en plantspesies-rykdom tot die vereiste vlakke te herstel nie, maar wel die weidingskapasiteit-doelwit bereik het. Hierdie persele benodig aanpassingsbestuur om plantbedekking- en plantspesiesrykdom-doelwitte te bereik. Die perseel wat onlangs gerehabiliteer is, het binne twee jaar na rehabilitasie die drie-jaar plantbedekking- en plantspesiesrykdom-doelwitte, sowel as die weidingskapasiteitdoelwit bereik. Daarom moet Namakwa Sands voortgaan om die huidige rehabilitasiemetode te gebruik. Rehabilitasie moet egter in die toekoms in veelvoudige stadiums gedoen word om die mortaliteit van kwekery-steggies te verminder en om die terugkeer van laatsuksessionele spesies na gerehabiliteerde persele te fasiliteer. Die volhoubaarheid van kleinveeboerdery op weiveld met die minimum vereiste weidingskapasiteit word betwyfel en vereis verdere ondersoek. LFA kan ‘n bruikbare instrument wees om siklering van voedingstowwe en grondstabiliteit te monitor by Namakwa Sands indien genoeg repliserings gebruik word. LFA kan egter nie in die huidige vorm gebruik word om waterinfiltrasie by Namakwa Sands te assesseer nie, aangesien daar aannames in die berekening van die indeks is wat nie juis is in die Namakwaland omgewing nie. Landskapfunksionering behoort jaarliks gemoniteer te word om plantopnames aan te vul.
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Banerjee, Monisha J. « Multiple Approaches to the Restoration of Disturbed Desert Land ». Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/193798.
Texte intégralRésumé :
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.
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Labbe, Richard James. « Watershed restoration limitations at the abandoned reclaimed Alta Mine, Jefferson County, MT ». Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/labbe/LabbeR0508.pdf.
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Blood, Jeremy Russell. « Monitoring rehabilitation success on Namakwa Sands heavy minerals mining operations, Namaqualand, South Africa ». Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2310.
Texte intégralRésumé :
Thesis (MScConsEcol(Conservation Ecology and Entomology)--University of Stellenbosch, 2006.Anglo American Corporation’s Namakwa Sands heavy minerals mining and beneficiation operation has been strip-mining a heavy mineral deposit, rich in the commercially valuable minerals ilmenite, rutile and zircon, since September 1994. The mine is located in the vicinity of Brand-se-Baai on the west coast of South Africa, approximately 385 km north of Cape Town. Strip-mining causes total destruction of natural ecosystems through the removal of vegetation and soil in the area where mining is being undertaken. Namakwa Sands has been rehabilitating mined out areas as the mining front moves forward. Due to the difficulty of rehabilitating mined out areas as a result of harsh environmental factors, Namakwa Sands has initiated various research projects to gain an understanding of the baseline conditions and ecosystem function in order to increase plant cover and biodiversity on post-mined areas. This on-going research and the development of rehabilitation and mining techniques have resulted in the implementation of four rehabilitation techniques varying in investment of topsoil replacement, seeding and plant translocation. This study assesses the success and effectiveness of these techniques in terms of various vegetation and soil parameters. In addition, those parameters that are considered useful for monitoring are identified. This study indicated that topsoil replacement and plant translocation facilitate the return of similarity, species richness, species diversity and vegetation cover to post-mined areas. The rehabilitation site that had the greatest amount of biological input (topsoil replacement and plant translocation) appeared to be the most successful technique in facilitating vegetation recovery similar to reference sites. In comparison, the site that had the least amount of biological input performed the worst and requires adaptive management, e.g. reseeding and / or plant translocation. Namakwa Sands should continue to replace topsoil in all future rehabilitation efforts and, when possible (e.g. after sufficient winter rain), continue to translocate species in multi-species clumps. In terms of species selected for translocation, Othonna cylindrica, Ruschia versicolor and Lampranthus suavissimus should be considered for future large-scale translocation projects. Zygophyllum morgsana appears to be more difficult to re-establish under the current climatic conditions (below average rainfall). The long-term viability of rehabilitated Z. morgsana populations needs to be determined before considering this species for any future large-scale translocation purposes. No translocated Asparagus spp. individuals survived and should therefore not be considered for any further translocation purposes. The grass Ehrharta calycina, which is dominant in the site seeded, should continue to be considered for future seeding. Species and functional diversity appear to be the most limiting factors within all the rehabilitation sites and Namakwa Sands will not be able to meet their long-term objective of small-stock farming if diversity and the number of palatable species do not increase significantly. Adaptive management should seriously be considered in order to speed up this process. Alternatively, an appropriate grazing strategy, which is related to the Tetragonia fruticosa dominated vegetation within rehabilitation sites, would need to be determined and adopted.More time is needed to ameliorate the rehabilitated soil profiles to the same level as in reference sites, especially with regard to carbon, pH and sodium levels. In order to increase organic matter within rehabilitation areas, Namakwa Sands should consider creating clumps with cleared vegetation from the mining front. Since the long-term rehabilitation goal has not been achieved, Namakwa Sands will need to continue to monitor plant and soil changes until it has been achieved. The objectives of the current rehabilitation programme are limited and Namakwa Sands should develop additional objectives relating to the structure and function of the natural vegetation. This will give a better indication of whether rehabilitation sites are progressing towards the desired end point and if adaptive management is required. In addition, the current monitoring programme (vegetation survey) implemented at Namakwa Sands could be improved by increasing the vegetation parameters to be monitored. It is recommended that the following vegetation parameters be monitored as part of the long-term monitoring programme: species composition and similarity, species richness, species diversity, vegetation cover, species dominance, vertical structure and functional diversity of the vegetation (clumps and inter-clumps). It is also recommended that carbon, pH and sodium of soil profiles be monitored as part of the long-term monitoring programme. These parameters should not be seen as exhaustive as this study only considered various vegetation parameters and soil chemistry between rehabilitation and reference sites. The results of other studies on the fauna, mycorrhiza, insects, etc. should also be taken into consideration and the monitoring parameters expanded accordingly.
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Bleby, Timothy Michael. « Water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on mine rehabilitation sites in the jarrah forest of south-western Australia ». University of Western Australia. School of Plant Biology, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0004.
Texte intégralRésumé :
[Truncated abstract. Please see the pdf format for the complete text. Also, formulae and special characters can only be approximated here. Please see the pdf version for an accurate reproduction.] This thesis examines the water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on bauxite mine rehabilitation sites in the jarrah forest of south-western Australia. The principal objective was to characterise the key environment and plant-based influences on tree water use, and to better understand the dynamics of water use over a range of spatial and temporal scales in this drought-prone ecosystem. A novel sap flow measurement system (based on the use of the heat pulse method) was developed so that a large number of trees could be monitored concurrently in the field. A validation experiment using potted jarrah saplings showed that rates of sap flow (transpiration) obtained using this system agreed with those obtained gravimetrically. Notably, diurnal patterns of transpiration were measured accurately and with precision using the newly developed heat ratio method. Field studies showed that water stress and water use by jarrah saplings on rehabilitation sites were strongly seasonal: being greatest in summer when it was warm and dry, and least in winter when it was cool and wet. At different times, water use was influenced by soil water availability, vapour pressure deficit (VPD) and plant hydraulic conductance. In some areas, there was evidence of a rapid decline in transpiration in response to dry soil conditions. At the end of summer, most saplings on rehabilitation sites were not water stressed, whereas water status in the forest was poor for small saplings but improved with increasing size. It has been recognised that mature jarrah trees avoid drought by having deep root systems, however, it appears that saplings on rehabilitation sites may have not yet developed functional deep roots, and as such, they may be heavily reliant on moisture stored in surface soil horizons. Simple predictive models of tree water use revealed that stand water use was 74 % of annual rainfall at a high density (leaf area index, LAI = 3.1), high rainfall (1200 mm yr-1) site, and 12 % of rainfall at a low density (LAI = 0.4), low rainfall (600 mm yr-1) site, and that water use increased with stand growth. A controlled field experiment confirmed that: (1) sapling transpiration was restricted as root-zone water availability declined, irrespective of VPD; (2) transpiration was correlated with VPD when water was abundant; and (3) transpiration was limited by soil-to-leaf hydraulic conductance when water was abundant and VPD was high (> 2 kPa). Specifically, transpiration was regulated by stomatal conductance. Large stomatal apertures could sustain high transpiration rates, but stomata were sensitive to hydraulic perturbations caused by soil water deficits and/or high evaporative demand. No other physiological mechanisms conferred immediate resistance to drought. Empirical observations were agreeably linked with a current theory suggesting that stomata regulate transpiration and plant water potential in order to prevent hydraulic dysfunction following a reduction in soil-to-leaf hydraulic conductance. Moreover, it was clear that plant hydraulic capacity determined the pattern and extent of stomatal regulation. Differences in hydraulic capacity across a gradient in water availability were a reflection of differences in root-to-leaf hydraulic conductance, and were possibly related to differences in xylem structure. Saplings on rehabilitation sites had greater hydraulic conductance (by 50 %) and greater leaf-specific rates of transpiration at the high rainfall site (1.5 kg m-2 day1) than at the low rainfall site (0.8 kg m-2 day1) under near optimal conditions. Also, rehabilitation-grown saplings had significantly greater leaf area, leaf area to sapwood area ratios and hydraulic conductance (by 30-50 %) compared to forest-grown saplings, a strong indication that soils in rehabilitation sites contained more water than soils in the forest. Results suggested that: (1) the hydraulic structure and function of saplings growing under the same climatic conditions was determined by soil water availability; (2) drought reduced stomatal conductance and transpiration by reducing whole-tree hydraulic conductance; and (3) saplings growing on open rehabilitation sites utilised more abundant water, light and nutrients than saplings growing in the forest understorey. These findings support a paradigm that trees evolve hydraulic equipment and physiological characteristics suited to the most efficient use of water from a particular spatial and temporal niche in the soil environment.
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Sonnenberg, Rob. « Development of aquatic communities in high-altitude mine pit lake systems of west-central Alberta ». Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, 2011, 2011. http://hdl.handle.net/10133/3106.
Texte intégralRésumé :
Reclamation on the Cardinal River and Gregg River coal mines includes the construction of mine pit lakes connected to stream environments. Key physical, chemical and biological parameters of these “truck and shovel” lakes and their streams were investigated, and hypotheses regarding ecosystems and populations were tested. Findings include:
Sphinx Lake and Pit Lake CD exhibit meromictic (partial-mixing) tendencies, but
still function in a similar fashion to shallower, natural sub-alpine lakes.
Elevated selenium concentrations as high as 16 ug/g (dry weight) were recorded
in Rainbow trout (Oncorhynchus mykiss) eggs taken from gravid Sphinx Lake and
Pit Lake CD fish. Potential detrimental effects associated with the
bioaccumulation of selenium on fish reproduction were not observed.
Stream water temperatures downstream of Sphinx Lake and Pit Lake CD were
significantly warmer than in inlet streams and streams without pit lakes.
Streambed concretions caused by calcite precipitation were documented and
found to affect portions of the upper Gregg River basin. Remediation of this
concretion is important for sustainability of trout populations.
Aquatic communities including fish, invertebrates, zooplankton and aquatic plants
are present in these pit lake systems. Athabasca Rainbow trout populations are
self-propagating (spawning at the outlets) with higher densities downstream than
there were prior to lake reclamation.
The development of sub-alpine mine-pit lakes connected to the stream environment
appears to be an appropriate and beneficial reclamation technique in this area.xvi, 224 leaves : col. ill., map ; 28 cm
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Gherardi, Mark James. « Availability and management of manganese and water in bauxite residue revegetation ». University of Western Australia. Soil Science and Plant Nutrition Discipline Group, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0038.
Texte intégralRésumé :
[Truncated abstract] Industrial processing to refine alumina from bauxite ore produces millions of tonnes of refining residue each year in Australia. Revegetation of bauxite residue sand (BRS) is problematic for a number of reasons. Harsh chemical conditions caused by residual NaOH from ore digestion mean plants must overcome extremely high pH (initially >12), saline and sodic conditions. At such high pH, manganese (Mn) is rapidly oxidised from Mn2+ to Mn4+. Plants can take up only Mn2+. Thus, Mn deficiency is common in plants used for direct BRS revegetation, and broadcast Mn fertilisers have low residual value. Added to this, physical conditions of low water-holding capacity and a highly compactable structure make BRS unfavourable for productive plant growth without constant and large inputs of water as well as Mn. However, environmental regulations stipulate that the residue disposal area at Pinjarra, Western Australia, be revegetated to conform with surrounding land uses. The major land use of the area is pasture for grazing stock. Hence, pasture revegetation with minimum requirement for fertiliser and water application is desirable. This thesis investigates a number of avenues with potential for maintaining a productive pasture system on BRS whilst reducing the current level of Mn fertiliser and irrigation input. Emphasis was placed on elucidation of chemical and physical factors affecting Mn availability to plants in BRS
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Mothapo, Makgamatho Godfrey. « Economic evaluation of bamboo cultivation and potential yield on rehabilitated mine sites ». Thesis, 2017. https://hdl.handle.net/10539/24092.
Texte intégralRésumé :
Thesis is submitted in partial fulfilment for the degree of Master of Science in Metallurgical Engineering to the Faculty of Engineering and the Built Environment, at the University of the Witwatersrand, Johannesburg, 2017Abandoned mines in South Africa have created a series of environmental legacies around the mining community in the form of health hazard (air pollution), land degradation and illegal mining activities. The biggest mine environmental legacy that is being addressed today in South Africa is that of abandoned mines, particularly asbestos and the process of cleaning up asbestos mining dumps in South Africa as implemented by Mintek (state owned mineral processing and metallaurgical research instistute)on behalf of Department of Mineral Resources (DMR) and this form the main basis of this research study. The history of abandoned mines, particularly asbestos mining, is that the mining peaked and took place during the time when there were no environmental regulations forcing mining companies to take control of their waste. The only legislation was the Atmospheric Pollution Prevention Act (Act No.45 of 1965). The Mineral Act, which regulated most of the mining activity in South Africa was promulgated in 1991 and was enacted as Act No.50 in 1991. Apart from the environmental challenges, these mines are located in rural areas with high unemployment levels and poor infrastructure, and therefore all solutions would require these matter to be addressed as well. This study was based on a literature review involving bamboo as a potential vegetation cover to be grown on abandoned mineland both for rehabilitation and with intention to harvest it for energy use. This would hope to address some of the socioeconomic issues within the communities surrounding such abandoned asbestos mines. Penge area in the Limpopo Province is proposed as the site for a pilot study for such bamboo cultivation. Bamboos are a large group of rapidly growing woody grasses, mainly found in the IndoChina regions of the world that can be sustainably managed in short-cycle harvesting schemes. They offer many benefits like erosion control, architectural properties for rural construction activities and can be used as biomass feedstock for the bioenergy economy. The results of this study indicate that it is possible to grow bamboo in the Penge based on its physio-climatic conditions. The literature review proposes , Bambusa balcooa, Dendrocalamus asper, Dendrocalamus strictus and Phyllostachys edulis as suitable bamboo species for the region. Based on rudimetary simple evaluation model the area will produce 14 tonnes/ha/year of biomass in the 5th year of harvesting, increasing to and stabilizing to 47 tonnes /ha/year in the 7th year and it has proven economically feasible to proudce energy from the amount of feedstock generated.
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Bellette, Marc. « After the goldrush : the success of ecological restoration following mining in the Box and Ironbark Forests, North Central Victoria ». Thesis, 1999. https://eprints.utas.edu.au/19072/1/whole_BelletteMarc1999_thesis.pdf.
Texte intégralRésumé :
The new science of restoration ecology offers those who work towards ecological
restoration an evaluative framework for measuring success. This research project
considers the restoration work carried out on four mined sites in the Box and Ironbark
Forest Ecosystem of North Central Victoria. To measure success, vegetation cover and
height, along with thirteen environmental variables and three site characteristics, were
recorded in four mine sites and compared to nearby forest controls. It was found that
mined sites had fewer native species than the control sites, and soil fertility and litter
cover were less. Five floristic communities were described from the mined areas and
controls, two of which are restricted to mined areas. Global Non-parametric Multi
Dimensional Scaling of the vegetation data and vector fitting of the environmental and
site variables also showed that strong floristic differences exist between mined and
control areas at most sites. As restoration attempts were similar at each site, ecosystem
resilience was considered as the main contributing factor to the different degrees of
success. It was found that mined areas with prolonged disturbance regimes shared less
in common with their control. Weed cover was not found to be significantly different
between the controls and mined areas. This study serves as baseline data for long term
research and recommends that clear goals and objectives need to be implemented in
determining successful mine site restoration in the Box and Ironbark Ecosystem.
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Stauffer, Glenn E. « Nesting ecology and site fidelity of grassland sparrows on reclaimed surface mines in Pennsylvania ». 2008. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2686/index.html.
Texte intégral
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Krisnayanti, Baiq Dewi. « Sustainable restoration of mine sites : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University / ». 2009. http://hdl.handle.net/10182/1598.
Texte intégral
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Dawson, RS. « Natural colonisation and rehabilitation of a copper smelter desert, Mount Lyell, western Tasmania ». Thesis, 1996. https://eprints.utas.edu.au/19659/1/whole_DawsonRoger1997_thesis.pdf.
Texte intégralRésumé :
This thesis investigates patterns of soil contamination and natural colonisation in an area deforested by a long-established, but decommissioned, copper smelter at Mount Lyell in western Tasmania. The rehabilitation of this area is investigated by modifying colonisation and species performance in relation to edaphic factors in accordance with succession management models.
The distribution of soluble metals in soils along transects of increasing, downwind displacement from the smelter stacks provided evidence of Cu/Zn contamination and Al mobilization. A higher than expected soil pH suggested a partial reversal of the process of soil acidification by SO2 deposition. This may, in part, explain relatively low, near-smelter contamination levels at Mount Lyell in comparison to similar sites in the vicinity of smelters of world-renown. Nevertheless, colonising species grown in Mount Lyell soils exhibited severe growth abnormalities and these were linked to elevated water-extractable metal concentrations.
A survey of the vascular flora, and multivariate analysis, were used to describe the composition and distribution of vegetation colonising the denuded western slopes of Mount Lyell. Compositional trends were explored in relation to edaphic factors by vector fitting, and a numerical classification of survey sites was used to group sites by characterising species coincidences. The classification was used to describe and map spatially distinct colonising communities that differed demonstrably in their tolerance to the phytotoxic metals present in the soils. Species with differential tolerances to the contaminants were identified. The naturalised, exotic grass Agrostis capillaris, was a wide-spread, metal-tolerant colonising species. In contrast, many local trees and shrubs were intolerant of the extreme site conditions. A strong spatial correspondence was evident between the colonising communities and contamination patterns in the vicinity of the smelter installations.
Rehabilitation methods for severely eroded sites adjacent to the original smelters were investigated. Emphasis was placed on broadcast sowing as a means of native species re-introduction. A novel, non-destructive, mechanical seedbed preparation method was compared to a conventional method and was found to provide comparable seedling establishment. Low impact, seedbed preparation and application methods for steep, eroded slopes were also compared and dissimilar methods were found to enhance the establishment of colonising Acacia species. The ameliorative effects of field applications of lime on the growth of colonising seedlings were evaluated.
The reclamation of Mount Lyell is discussed with reference to patterns of natural colonisation.
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De, Kloe Nicolette. « Methods of ground improvement applied during the rehabilitation process in the mining industry ». Thesis, 2011. http://hdl.handle.net/10210/4087.
Texte intégralRésumé :
M.Ing.As of 1991 new legislation demands that all existing and proposed mines have to submit and implement a rehabilitation plan. This plan consists of numerous phases and can cost a fair amount of money that almost none of the mines have budgeted for. During the rehabilitation process the improvement of the ground on, for example, discard dumps or slurry ponds, are not stable or adequate to enable the civil engineer to ensure stability for the new development. This can include a new sports field or low cost housing or just the peace of mind that the dump is stable and looks natural. This thesis will aim to introduce some of the numerous different ground improvement techniques that are available in South Africa and overseas.
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« The influence of angle and aspect on the established vegetative cover on the slopes of rehabilitated coal discard dumps in Mpumalanga ». Thesis, 2009. http://hdl.handle.net/10210/2099.
Texte intégralRésumé :
M.Sc.The decommissioning of mines and mining-related activities brings about the onset of rehabilitation. A legacy that most coal mines must address is the rehabilitation of the coal discard dumps that are generated by the beneficiation process of the raw coal. Rehabilitation involves the shaping and covering with a topsoil layer of these coal discard dumps. The topsoil layer is then revegetated to provide a stable form of protection against erosion. Considerations taken into account regarding the rehabilitation of coal discard dumps include the final slope angle, physical constraints i.e. railways or rivers, a source of topsoil and the grass species to be sown. Once the dump has been shaped, capped and seeded, regular applications of fertilizer take place for a defined period of time. This is to accelerate the growth of the grasses, as well as to stabilise the nutrient levels in the topsoil capping. Ingwe Mine Closure Operations (MCO), part of Ingwe Collieries Limited, is the business unit entrusted with the management and successful rehabilitation of Ingwe’s defunct operations. All of the coal discard dumps sampled in this study are found on such defunct operations. These coal discard dumps have been rehabilitated to a very high standard by MCO, and in most cases exceed the minimum requirements stipulated by law and guideline documents. This study and the results obtained from it reflect this. This study investigated, in terms of defined types of cover, whether or not there is a statistically significant difference between the: • six coal discard dumps from which data were collected; • five different defined slope aspects; • two groups of slope angles; and • slope angle and slope aspect in terms of cover. The data collected was analysed statistically, so as to determine whether significant differences (95 percentile confidence level), in terms of cover, exist. The purpose of this was to determine whether or not a preferred slope aspect or slope angle group could be identified for the six coal discard dumps sampled. By identifying a preferred slope aspect or slope angle group, companies could alter the design of operational or defunct dumps so as to maximise these. This would make the rehabilitation of the dump more sustainable and could possibly reduce aftercare costs. Through statistical analysis of the data collected it was determined that: • of the six coal discard dumps sampled, significant differences did exist between some of the dumps regarding basal cover, plant litter cover and bare ground. As each dump is different with its own specific micro-climate, this can be expected. The age of the dumps could also have played a role in terms of development; • of the five different defined slope aspects analysed, no significant differences existed between any of them; • of the two groups of slope angles analysed, no significant difference existed between them; and • no relationship between slope angle and slope aspect, in terms of cover, could be established. The analysis of the data collected was done by means of ANOVA one-way tests, coupled with Post Hoc Tests and Contrast Tables. The results of the statistical analysis were evaluated by the STATCON Department of the Rand Afrikaans University for accuracy. The data and the statistical analysis thereof were found to be satisfactory and correct. Various other statistical analyses were conducted on the data, but the results obtained from these tests were all the same as that of the original data analysis. These analyses included the Univariate Analysis of Variance, T-tests and Mann-Whitney tests.
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Beukes, Werner. « Generic guidelines for rehabilitation of borrow pits on linear pipeline projects ». Thesis, 2010. http://hdl.handle.net/10210/3072.
Texte intégralRésumé :
M.Sc.This study focuses on the rehabilitation of borrow pits on linear pipeline projects. In the past there have been many attempts to rehabilitate borrow pits to an ecological acceptable manner. Recently legislation has become more stringent regarding mine closure and rehabilitation. With the introduction of the new Mineral and Petroleum Development Act (MPRDA 28 of 2002), there has been an increase of awareness towards the immediate environment. As this project was a challenge in itself, there were no clear and concise methods in the Act that provide guidelines for final rehabilitation. Normally borrow pits as used on road concessions for material sourcing is left as different landforms like before excavation. The main reason for this is that materials are removed from the pits and not replaced, resulting in areas that are usually lower than their original ground levels. Some unwanted screened material will return to these borrow pits but will not complement what the original level should be. These borrow pits are usually clearly visible as low lying areas filled with water alongside roads. The Vaal River Eastern Subsection Augmentation Project (VRESAP) pipeline borrow pits were unique in the sense that not only material from screening activities were replaced, but also material excavated from the trench were replaced into the borrow pits. What makes this study unique is the fact that an opportunity was presented and clearly stipulated by the standard environmental management plan (SEMP) that borrow pits had to be filled back to their original ground levels or an acceptable level agreed on by the landowner. With this unique project, unique problems arose causing excess material amounting to 327 700 m³, available from the pipeline cavity. External spoil areas had to be promulgated and managed as part of site. This study through its various elements addresses some of the main problems encountered on VRESAP by looking at soil analysis, monitoring regimes, pre and post land use and other mechanisms from literature studies used on similar projects in the mining industry. vii The study also provides recommendations to the reader for future pipeline developments as well as conclusions made by the author. The recommendations made, include ways of rehabilitation planning through trials and errors made on site. Various conclusions were made that would substantiate this study in perspective to user-friendly and practical approaches.
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Crous, Nadia Catharina. « Cost effective rehabilitation of an open cast chrome mine in the North West Province ». Thesis, 2009. http://hdl.handle.net/10210/2089.
Texte intégral
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Lappin, Kerri Lynne. « On the origin of virtual wetlands by means of computer aided selection or the preservation of favoured places in the struggle for functional wetlands ». Master's thesis, 2010. http://hdl.handle.net/10048/919.
Texte intégralRésumé :
Thesis (M.Sc.)--University of Alberta, 2010.Title from PDF file main screen (viewed on Apr. 23, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Renewable Resources, University of Alberta. Includes bibliographical references.
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Harrison, Peter Carleton. « A critical analysis of how Independent Power Producers (IPP’s) can help to secure a sustainable future for post-mining towns in South Africa through new models of architectural practices, to promote the renewal of architecture as a means of creating new realities and being drivers of sustainable change ». Thesis, 2018. https://hdl.handle.net/10539/26514.
Texte intégralRésumé :
Thesis is submitted in partial fulfilment for the degree of Master of Architecture to the Faculty of Engineering and the Built Environment, School of Architecture and Planning at the University of the Witwatersrand, Johannesburg, 2018This thesis aims to understand the role that Independent Power Producers (IPP’s) can play in the renewal of architectural firms in creating new realities and how these firms can once again become drivers of social change. Kathu (Northern Cape), a steel mining town, is facing the reality that it will have to survive without a mining house and the community funding that results from its operations soon. There are three IPP’s within a 50km radius of Kathu. Under the current funding structure all 3 IPP’s have to contribute to socio-economic development (SED) and enterprise development (ED) within Kathu. According to the Independent Power Producers Procurement Programme (IPPP’s), IPP’s are required to provide 1% of gross turnover to community funds for SED and ED development programmes. Where this funding differs from funding obtained from mining houses is that renewable energy is effectively limitless. Despite IPP’s having a projected lifespan of 20 years they will continue to be redeveloped and upgraded. These upgrades will allow for longevity of revenue, which in turn allows for sustained support for the communities surrounding them. Funding structures that are being used to disseminate mining house funds to the communities are suffering from governance issues. This means that the communities do not receive the most effective or necessary forms of development. Through a new typology of architectural practice, the way these funds are managed and utilised can create better environments for those communities. This new typology of architectural firm must move away from the corporate and profit driven nature of modern architectural firms and more towards a ‘Rural Studio’ model. This is where the primary focus is on the community and how to best serve the needs of the people. In doing so SED projects would be more effective in bringing about social change, creating new realities for communities and drivers of sustainability in post-mining towns in South Africa.
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