Дисертації з теми "Soils Environmental aspects Australia"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Soils Environmental aspects Australia.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Soils Environmental aspects Australia".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
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.
Повний текст джерелаАнотація:
[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
2
Lalor, Briony Maree. "An assessment of the recovery of the microbial community in jarrah forest soils after bauxite mining and prescription burning." University of Western Australia. School of Earth and Geographical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0037.
Повний текст джерелаАнотація:
[Truncated abstract] Recovery of soil nutrients, microbial populations and carbon (C) and nitrogen (N) cycling processes are critical to the success of rehabilitation following major ecosystem disturbance. Bauxite mining represents a major ecosystem disturbance to the jarrah (Eucalyptus marginata) forest in the south-west of Western Australia. Mining has created a mosaic of mined areas in various stages of succession surrounded by non-mined forest areas. Initial site preparations within rehabilitation areas such as contour ripping alter soil structure (creation of mound and furrows) and over time also influence the distribution of vegetation and litter. Current performance criteria developed by industry, government and other stakeholders have determined that before post-bauxite mined areas of jarrah forest can be integrated back into normal forest management practises they should be functional and demonstrate resilience to normal forest disturbances such as fire. Furthermore, resilience should be of a manner comparable to non-mined analogue forest sites. Currently little is known of the resilience of microbial communities and C and N cycling in rehabilitation sites to normal forest disturbances such as prescription burning. As such, before rehabilitated jarrah forests can be successfully integrated into broad scale forest management regimes, a more thorough knowledge of the potential impacts of burning practises on the soil microbial community and C and N cycling processes in these systems is required. ... While there are similar rates of C and N cycling the underlying microbial community structure was distinctly different; implying a high degree of functional redundancy with respect to C and N cycling. Differences in the C and N cycling and structure of the microbial communities were likely to be due to differences in soil environmental conditions (i.e. soil alkalinity/acidity, soil moisture) and C substrate availability which influence the physiological status of the microbial community and in turn are related to successional age of the forests. Results also suggest that the measurement of CLPP can be a useful approach for assessment of changes in the functional ability of microbial communities. However, the interpretation of how well these rehabilitation forests have recovered heterotrophic abilities was greatly affected by the methodological approach used (e.g. MicroRespTM or Degens and Harris, 1997). Importantly, results from Chapter 4 and 5 suggested that the effects of a moderate prescription fire on C and N processes, CLPP and microbial community structure of 18 year old rehabilitation forests are likely to be short-lived (< 2 years). Furthermore, the effects of the moderate spring prescription fire were not large enough to decouple C and N cycling processes over the short-term (< 1 years) which suggests that by 18 years of age rehabilitation forests demonstrate comparable functional resilience to a moderate prescription burn.
3
Harris, Mark Anglin. "Some organic amendments for heavy metal toxicity, acidity and soil structure in acid-sulphate mine tailings /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phh3148.pdf.
Повний текст джерела
4
Heshmatti, Gholam Ali. "Plant and soil indicators for detecting zones around water points in arid perennial chenopod shrublands of South Australia /." Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phh584.pdf.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of Adelaide, Dept. of Botany, 1997.Errata page is behind title page (p. i). Copies of author's previously published articles inserted. Includes bibliographical references (leaves 121-156).
5
Weggler-Beaton, Karin M. "The beneficial and detrimental effects of sewage sludge applications in South Australia." Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phw4113.pdf.
Повний текст джерела
6
Speldewinde, Peter Christiaan. "Ecosystem health : the relationship between dryland salinity and human health." University of Western Australia. School of Population Health, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0127.
Повний текст джерелаАнотація:
Australia is experiencing widespread ecosystem degradation, including dryland salinity, erosion and vegetation loss. Approximately 1 million hectares (5.5%) of the south-west agricultural zone of Western Australia is affected by dryland salinity and is predicted to rise to 5.4 million hectares by 2050. Such degradation is associated with many environmental outcomes that may impact on human health, including a decrease in primary productivity, an increase in the number of invasive species, a decrease in the number of large trees, overall decrease in biodiversity, and an increase in dust production. The resulting degradation affects not only farm production but also farm values. This study examines the effects of such severe and widespread environmental degradation on the physical and mental health of residents. Western Australia has an extensive medical record database which links individual health records for all hospital admissions, cancer cases, births and deaths. For the 15 diseases examined in this project, the study area of the south west of Western Australia (excluding the capital city of Perth) contained 1,570,985 morbidity records and 27,627 mortality records for the 15 diseases examined in a population of approximately 460,000. Environmental data were obtained from the Western Australian Department of Agriculture?s soil and landscape mapping database. A spatial Bayesian framework was used to examine associations between these disease and environmental variables. The Bayesian model detected the confounding variables of socio-economic status and proportion of the population identified as Aboriginal or Torres Strait Islander. With the inclusion of these confounders in the model, associations were found between environmental degradation (including dryland salinity) and several diseases with known environmentally-mediated triggers, including asthma, ischaemic heart disease, suicide and depression. However, once records of individuals who had been diagnosed with coexistent depression were removed from the analysis, the effect of dryland salinity was no longer statistically detectable for asthma, ischaemic heart disease or suicide, although the effects of socio-economic status and size of the Aboriginal population remained. The spatial component of this study showed an association between land degradation and human health. These results indicated that such processes are driving the degree of psychological ill-health in these populations, although it remains uncertain whether this 4 is secondary to overall coexisting rural poverty or some other environmental mechanism. To further investigate this complex issue an instrument designed to measure mental health problems in rural communities was developed. Components of the survey included possible triggers for mental health, including environmental factors. The interview was administered in a pilot study through a telephone survey of a small number of farmers in South-Western Australia. Using logistic regression a significant association between the mental health of male farmers and dryland salinity was detected. However, the sample size of the survey was too small to detect any statistically significant associations between dryland salinity and the mental health of women. The results of this study indicate that dryland salinity, as with other examples of ecosystem degradation, is associated with an increased burden of human disease.
7
Sun, Hua. "Digital terrain modelling of catchment erosion and sedimentation /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phs9565.pdf.
Повний текст джерела
8
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.
Повний текст джерелаАнотація:
[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
9
Campbell, Robert. "Understanding and disrupting institutional settings : using networks of conversations to re-imagine future farming lives." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/603.
Повний текст джерелаАнотація:
Farmers in Australia and elsewhere face the challenge of remaining profitable whilst dealing with adverse structural arrangements and public expectations to better manage environmental degradation. This thesis draws on arguments that dominant paradigms in agricultural science and environmental management have often been ineffective in addressing these apparently competing demands and appear poorly suited to ‘messy’ situations characterized by uncertainty and complexity, and in which diverse stakeholders are motivated by varying goals and values. Engaging with such situations requires a philosophy and methodology that accepts a multiplicity of perspectives and which seeks to learn about and reflect upon novel ways of thinking and acting. Among the underlying ideas that have shaped this project is the importance of recognising the assumptions and commitments that researchers bring to their practice in order that traditions are not uncritically reproduced and that the products of our thinking are not reified. Regarding farming as less a set of technical practices and more as a human activity taking place within broader economic, social, cultural and ecological contexts, I sought to engage a group of farmers in southern Western Australia in a process of taking action to address an issue of common concern that would help them to live and farm well in their district. My role as both researcher and facilitator of conversations was driven by a commitment to dialogue as a process of meaning making and relationship building. Together we explored some of the broader contexts within which the narrower conceptions of economic and ecological problems are often uncritically placed. Taking concrete action together however proved beyond the scope of my research. The challenge of feeding ourselves while better caring for the land and each other will require imaginative as well as technical resources. To this end I have also sought to sketch out some of the creative possibilities contained within the health metaphor as it is applied to soil, arguing that its use as a proxy for quality or condition fails to utilize its disruptive potential.
10
Gill, Nicholas Geography & Oceanography Australian Defence Force Academy UNSW. "Outback or at home? : environment, social change and pastoralism in Central Australia." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Geography and Oceanography, 2000. http://handle.unsw.edu.au/1959.4/38728.
Повний текст джерелаАнотація:
This thesis examines the responses of non-indigenous pastoralists in Central Australian rangelands to two social movements that profoundly challenge their occupancy, use and management of land. Contemporary environmentalism and Aboriginal land rights have both challenged the status of pastoralists as valued primary producers and bearers of a worthy pioneer heritage. Instead, pastoralists have become associated with land degradation, biodiversity loss, and Aboriginal dispossession. Such pressure has intensified in the 1990s in the wake of the native Title debate, and various conservation campaigns in the arid and semi-arid rangelands. The pressure on pastoralists occur in the context of wider reassessment of the social and economic values or rangelands in which pastoralism is seen as having declined in value compared to ???post-production??? land uses. Reassessments of rangelands in turn are part of the global changes in the status of rural areas, and of the growing flexibility in the very meaning of ???rural???. Through ethnographic fieldwork among largely non-indigenous pastoralists in Central Australia, this thesis investigates the nature and foundations of pastoralists??? responses to these changes and critiques. Through memory, history, labour and experience of land, non-indigenous pastoralists construct a narrative of land, themselves and others in which the presence of pastoralism in Central Australia is naturalised, and Central Australia is narrated as an inherently pastoral landscape. Particular types of environmental knowledge and experience, based in actual environmental events and processes form the foundation for a discourse of pastoral property rights. Pastoralists accommodate environmental concerns, through advocating environmental stewardship. They do this in such a way that Central Australia is maintained as a singularly pastoral landscape, and one in which a European, or ???white???, frame of reference continues to dominate. In this way the domesticated pastoral landscapes of colonialism and nationalism are reproduced. The thesis also examines Aboriginal pastoralism as a distinctive form of pastoralism, which fulfils distinctly Aboriginal land use and cultural aspirations, and undermines the conventional meaning of ???pastoralism??? itself. The thesis ends by suggesting that improved dialogue over rangelands futures depends on greater understanding of the details and complexities of local relationships between groups of people, and between people and land.
11
Tiver, Fleur. "Vegetation patterns of eastern South Australia : edaphic control and effects of herbivory /." Title page, contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09pht623.pdf.
Повний текст джерела
12
Szota, Christopher. "Root morphology, photosynthesis, water relations and development of jarrah (Eucalyptus marginata) in response to soil constraints at restores bauxite mines in south-western Australia." University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0058.
Повний текст джерелаАнотація:
Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots. Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots.
13
Woods, William Eric. "Copper migration through petroleum-treated soils." Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722463.
Повний текст джерелаАнотація:
The purpose of the project was to determine the effect of various petroleum amendments on the migration rate of Cu. The petroleum amendments used in this research are frequently added to the soil surface in petroleum landfarming. Such petroleum wastes often contain significant amounts of Cu and other metals.Soil columns were amended with citric acid, used crankcase oil and Illinois crude oil. Each amendment was spiked (treated) with three different concentrations of Cu and each treatment was replicated three times. The columns were leached once per week, for ten weeks, with distilled water acidified to pH 4.5 to simulate acid rain. Leachate from the soil columns was analyzed weekly for total Cu. At the end of the ten week period, the soil was analyzed for Cu and TOC content at 7 cm intervals to determine the amount of migration by Cu and the organic amendments, resectively. The soil (a Glynwood silt loam) and the organic amendments were each analyzed for total Cu to determine background levels. The soil was analyzed for pH, TOC, electrical conductivity and soil texture.Analysis of the leachate and soil showed differential migration of Cu through the soil columns. Significant levels of Cu leached in the columns amended with citric acid (as high as 85.3 mg/L) in the first 3 weeks of the study. The Cu content of the leachate from columns amended with crude petroleum were at approximately background levels (5.5 mg/L) as was the leachate from columns amended with crankcase oil (0.2 mg/L). In the later weeks of the research, as the petroleum amendments were broken down by microorganisms, some Cu was chelated to small fragments of the petroleum and leached through the soil columns. Most of the Cu appeared to remain on the surface of the columns, bound to the petroleum amendments. Analysis of the soil, for total Cu content with depth, showed very little Cu accumulation at any depth in the soil column, beyond the soil surface. In most cases Cu levels remained near the background levels found in the control columns.Moderate correlation was found (r2 = .59 for crude oil; r2 = - .54 for crankcase oil; r2 = .85 for citric acid) between Cu levels and TOC levels in the soil columns with depth.From the results of the current study it can be inferred that practices such as petroleum landfarming and land disposal of some hazardous materials may allow for the migration of both the applied petroleum wastes and any metals which may be contained within.Department of Natural Resources
14
Cook, Nicola. "Bioavailability of trace metals in urban contaminated soils." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34934.
Повний текст джерелаАнотація:
There are two main components to the research: the theoretical and the experimental. Chapter 2 contains an analysis of the state of soil quality guidelines and the scientific methods used to determine them. A number of recommendations to improve soil quality criteria for trace metals are offered including the importance of considering bioavailability and the need to use realistic conditions, trace metal sources and organisms.A critical review of the literature dealing with predicting the availability of trace metals to plants is presented in Chapter 3. We found little agreement among hundreds of similar studies which relate plant metal uptake to the amount of metal extracted by selective chemical dissolution procedures. An extensive summary of the data shows clearly that the extraction methods are not widely applicable. Differences between individual soils, their metal retention capacities, as well as plant factors and environmental conditions contribute to the variability of the results. Alternative ways of assessing bioavailability are suggested.
The experimental component of the thesis focuses on the availability of trace metals to plants. In Chapter 4 the uptake of Cu from different soil pools was examined and the free metal ion (Cu2+) was found to be the best predictor of uptake by lettuce (Latuca sativa cv. Buttercrunch), ryegrass (Lolium perenne cv. Barmultra) and radish (Raphanus sativus cv. Cherry Belle).
In Chapters 5 and 6 we examined the effect of low-cost in-situ treatments on the availability of metals to plants in greenhouse and field experiments. Synthetic zeolites, P amendments, organic matter and clean soil were used and their effect on the bioavailability of Cd, Cu, Pb, Ni and Zn evaluated. The plants for the experimental work were lettuce and perennial ryegrass. Only the clean soil treatment was consistently effective in reducing the concentration of metals in the plant. We also wanted to determine whether the trace metals in the plant tissue came from the soil or from direct deposition of pollutants on the leaf surfaces. We found little evidence that metals in plants were a result of atmospheric fallout.
A method for the accurate analysis of total metal concentrations in a range of contaminated soils including those containing oil and grease was developed (Chapter 7). For this research the trace metals of concern are Cd, Cu, Ni, Pb and Zn---all commonly found in urban/industrial soils. The proposed method using HNO3/HClO4 has several advantages over the common HNO3/H2O2 procedure. We were able to digest larger soil samples and hence the final concentration of trace metals was usually in the range for analysis by inductively coupled plasma atomic absorption spectrometry or flame atomic absorption spectrometry.
15
Reyes, Delgadillo Dulce B. "Modeling natural attenuation of trace elements in soils." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101169.
Повний текст джерелаАнотація:
Trace elements added to the soil by human activities could contaminate it and occasionally cause a threat to environmental and human health. The toxicity and mobility of a trace element are affected by the element's solubility, which in turn is influenced by the soil properties. When mobile, trace elements can be leached out of the soil. If leaching occurs at a faster rate than atmospheric deposition, element concentrations in the soil will decrease by natural attenuation.We analyzed soil properties in 40 soils and their soil solutions to obtain a set of equations with the most significant predictors of As, Cd, Co, Cu, Mo, Ni, Pb and Zn in solution. The total element concentration and the pH were the best predicting variables of the amount of element in solution for all trace elements analyzed, while organic carbon and Al or Mn oxides also influenced the solubility of some trace elements. Using the equations predicting elemental solubility, we wrote a model for natural attenuation in the computer program Stella that considers atmospheric deposition as the input for trace elements and leaching as the output. Simulations were carried out for the 40 soils during 1,000 years with steady deposition inputs.
At current atmospheric deposition rates and the neutral to alkaline pH of these soils, attenuation occurred in most soils for Mo. For As, Cd, Co, Cu and Ni it occurred only in soils with abundant total element concentrations or an acidic pH. Minor retention occurred with Pb and Zn. Only Cd and Cu were of concern in leaching waters. The developed model can serve as a decision making tool in the selection of natural attenuation as a remediation strategy.
16
Grigg, Alasdair M. "An ecophysiological approach to determine problems associated with mine-site rehabilitation : a case study in the Great Sandy Desert, north-western Australia." University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0118.
Повний текст джерелаАнотація:
[Truncated abstract] Establishment of vegetation and ecosystem functioning is central to the mitigation of environmental impacts associated with mining operations. This study investigated the ecophysiological functioning of mature plants in natural vegetation and applied this knowledge to diagnose problems affecting plant health and causes of poor plant cover at a mine-rehabilitation site. Ecophysiological parameters, including plant water relations and mineral nutrition, were studied in conjunction with soil physical, hydraulic and chemical properties. The natural ecosystem at the study location in the Great Sandy Desert is characterised by sand dunes and interdunes with distinct plant communities on each. One of the most notable features of the vegetation is the presence of large Corymbia chippendalei trees high on the dunes and relatively small scattered shrubs in the interdunes. Triodia grasses (spinifex), dominate the vegetation in both habitats but different species occur in each; T. schinzii is restricted entirely to the dunes, and T. basedowii occurs only in the interdunes. It was hypothesised that the deep sandy dunes afford greater water availability but lower nutrient supply to plants in this habitat compared with those occurring in the lower landscape position of the interdunes. Water-relations parameters (leaf water potentials, stomatal conductance, d13C) revealed that dune plants, particularly woody species, displayed higher water status and water use than closely related and often congeneric plants in the interdunes. Nutrient concentrations in soils were significantly higher in the interdunes, but concentrations in foliage were similar for related species between habitats. It is concluded that the dunes provide a greater store of accessible water than the soil profile in the interdunes. ... Following an experimental wetting pulse equivalent to a summer cyclone event, A. ancistrocarpa plants displayed significant increases in stomatal conductance, leaf water potential and sap velocity in lateral roots within three days of irrigation at the natural site and two days at the rehabilitation site. Secondary sinker roots originating from distal sections of lateral roots were evidently supplying water to maintain hydraulic function in laterals, thus enabling a fast pulse response. This was accentuated at the rehabilitation site where roots were confined closer to the surface. These results indicate that plants at the rehabilitation site are more dependent on small pulses of water and have less access to deep reserves than plants at the natural site. It is concluded that high runoff losses and insufficient soil depth are major factors contributing to plant water stress, and combined with the direct impacts of erosion, are largely responsible for plant death and ultimately poor plant cover. These issues can be alleviated if cover soil depth is increased to more than 0.5 m and slope angles are reduced to <12o. This study demonstrates the value of an ecophysiological approach for diagnosing problems affecting plant establishment at mine-rehabilitation sites. Furthermore, it has provided recommendations that will improve the rehabilitation strategy and lead to the development of a well vegetated, resilient ecosystem on a stable and non-polluting land form.
17
Kennette, Debra. "The bioavailability of trace metals to soil invertebrates in urban contaminated soils." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/MQ44194.pdf.
Повний текст джерела
18
Ge, Ying 1974. "Trace metal speciation and bioavailability in urban contaminated soils." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21555.
Повний текст джерелаАнотація:
Urban soils are often contaminated with trace metals and the toxicity of the metals depends, in part, on their speciation in soil solutions. The objectives of this project were to estimate the metal speciation in urban soils and to evaluate the predictability of soil metal pools on plant uptake. The chemical speciation of Cd, Cu, Ni, Pb and Zn was estimated by using the Windermere Humic Aqueous Model (WHAM). In soil solutions, Cd, Ni and Zn were present mainly as free ions when the solutions were acidic and their organic complexes were dominant as the pH was over 7.5. The other two metals mostly formed complexes with organic ligands. The activities of Cd2+, Cu2+, Ni2+, Pb2+ and Zn 2+ were affected by soil pH and total soil metal burdens. All five metals were under-saturated with respect to the minerals which could potentially control the metal solubility.Metal uptake by plants in the contaminated railway yards was generally not correlated with free, dissolved and total soil metal pools. A pot experiment demonstrated better correlations between the metal pools and the metal content in wild chicory. Multiple regression analysis showed that the metals in the leaves and roots of wild chicory could be adequately predicted by the soil total metals and soil properties such as pH and exchangeable Ca.
19
Nkoe, Nozi 'Mabafokeng. "Assessment of cadium (Cd) and lead (Pb) contamination in the soils of pre-school facilities in the City of Cape Town." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/2014.
Повний текст джерелаАнотація:
Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2009.In the last two centuries, the natural state of the environment has changed significantly due to anthropogenic activities. With an estimated half-life of 15 - 1100 years for cadmium in soils, the metal remains a threat to the ecosystem. In general, most soils contain <1 mg/kg, except those contaminated from discrete sources or developed on parent materials with very high cadmium contents. Anthropogenic lead in soil has several well recognized major sources, namely, lead based paint, mining and smelting activities, manures, sewage sludge usage in agriculture and contamination from vehicle exhausts. Since lead is a heavy metal, over time it will settle down and build up in soil. The main aim of this study was to determine the degree of cadmium and lead contamination of soil, in and around selected pre-school facilities in the City of Cape Town (CCT). A number of pre-school facilities, particularly those nearby heavy traffic, were selected in the CeT. Natural soil and sand pit soil samples were collected and analysed for cadmium and lead. Low soil moisture is normally associated with high pH, as found in the present study. High pH values are in turn associated with low toxicity of metal contaminants. Most urban populations rely heavily on motor vehicles and vehicle-related pollution has been an increasing concern in recent years (before 2006). Air pollution in the CCT is trapped by inversion layers. In this study it has been found that cadmium is not a significant contaminant in the soils of pre-school facilities in the CCT. The Cape Town administration area was found to be the most contaminated with this metal. This study showed that the Cape Town administration area also had the highest lead concentrations in pre-school soils in the CCT. This can be attributed to the higher density of industry and traffic activities (study conducted pre-2006) in this area. There is a need for further research to determine the relationship between soil metal concentrations and blood metal levels, especially in children.
20
Carefoot, Janna. "Phosphorous leaching from coarse-textured soils amended with inorganic or organic fertilizers." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33725.
Повний текст джерелаАнотація:
Non-point source pollution of surface waters with phosphorous (P) transported from agricultural soils has emerged as a major environmental issue in the last decade. Regulations limiting P accumulation in surface soils have been established to protect surface water quality. Yet, little information is available on the quantities of P that may leach through soils and the factors influencing P leaching in agricultural soils. One important factor may be the type of fertilizer P applied, since it is known that P solubility varies among fertilizer sources. The purpose of this thesis was to quantify P leaching in soils amended with inorganic and organic fertilizers.In a field study, we found that the fertilizer P source (triple superphosphate, composted cattle manure, or a mixture of the two) did not affect soil test P concentration, the degree of soil P saturation, or P leaching in a sandy-loam soil. The soil test P level in the 0--15-cm depth (146 mg P kg -1) exceeded the critical limit of 66-mg kg-1 established in Quebec, and ortho-P and DOP concentrations in leachates collected from piezometers were generally higher than the provincial water quality standard of 0.03 mg P L-1. If transported from our study site, P leached through this coarse-textured soil could pose a threat to groundwater and surface water quality.
These findings were verified in the laboratory with two coarse-textured soils. We found that more NO3-N and DON were leached from soils receiving inorganic N and P fertilizers than composted cattle manure, but the amounts of ortho-P and DOP leached were not affected by fertilizer sources. In coarse-textured soils, the quantities of P leached can be substantial, but depends more on soil characteristics than the fertilizer P source.
21
Chen, Juan. "Mobility and environmental fate of norflurazon and haloxyfop-R methyl ester in six viticultural soils of South Australia /." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09AEVM/09aevmc518.pdf.
Повний текст джерела
22
Mácsik, Josef. "Soil improvement based on environmental geotechnics : environmental and geotechnical aspects of drainage of redox-sensitive soils and stabilisation of soils with by-products." Doctoral thesis, Luleå tekniska universitet, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-16786.
Повний текст джерелаАнотація:
I avhandlingen behandlas Miljögeotekniska problem som "dränering av redox-sensitiva jordar", "blockstabilisering av sulfidjord och torvjord" och " undersökning av nya vägmaterial". - Miljöproblem, kopplat till dränering och/eller urgrävning av redox-sensitiva jordar, som järnhaltiga moräner och sulfidjordar, behandlas i denna avhandling. Dräneringsproblem, orsakat av igensättning och korrosion, kan förutses genom att bedöma jord- och grundvattenkemin hos jord- respektive grundvattenprover. -Blockstabilisering är en grundläggningsmetod som används i organiska jordar, där dränering och urgrävning bör undvikas. I denna avhandling behandlas stabilisering av sulfidjord och torvjord med Portlandcement, Portlandcement/ Hyttsten och Portlandcement/LD-slagg. För kontroll av homogenitet hos stabiliserade fältprover från sulfidjord och torvjord har metoder, för respektive jord, tagits fram och föreslagits. Resultaten visar att stabilisering med Portland-cement och Hyttstenbaserade tillsatsmedel fungerar tillfredsställande, utan att de stabiliserade materialens halter av reglerade element/föreningar överskrider svenska riktvärden för känslig markanvändning. Portlandcement/LD-slagg ger bra stabiliseringsresultat men LD-slagg innehåller höga halter av lakbart Vanadin. - Geotekniska egenskaper hos ett jord- eller vägmaterial kan förbättras genom tillsättning av restprodukter som tillsatsmedel. Miljögeoteknisk undersökning bör därför utföras.Godkänd; 1999; 20061117 (haneit)
23
Ge, Ying 1974. "Speciation and complexation of trace metals in eastern Canadian soils." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82879.
Повний текст джерелаАнотація:
An important task of research on trace metals in soils is to evaluate how much metals are potentially bioavailable and may cause toxic effects. In this thesis, the chemical speciation and complexation of cadmium (Cd), copper (Cu), mercury (Hg) and lead (Pb) were examined in eastern Canadian soils collected from different locations around smelters. Our goal is to be able to predict metal binding in the soil solution and on the solid phase under a wide range of field conditions.In Chapter 2, speciation of Cd, Cu and Pb in the lysimeter soil solutions was determined using an ion exchange technique (IET) involving a resin column. The IET-speciation data were used to estimate the metal-dissolved organic carbon (DOC) binding constants using the non-ideal competitive adsorption (MICA)-Donnan model, which assumed a continuous distribution of binding affinities on the DOC molecule. The published Cd and Pb speciation data in a variety of soils (Chapter 3) were also used to test the effectiveness of two speciation models, the MICA-Donnan model and WinHumicV. Both models satisfactorily predicted the concentrations of Cd2+ and Pb2+. The two chapters of metal speciation demonstrated that the NICA-Donnan model could estimate the binding strength of organic matter in soil solutions.
Proton and metal complexation to the surface of soil particles (Chapters 4 and 5) was investigated using back-titration and batch adsorption procedures. It was shown that the surface binding of H+, Cd2+, Hg2+ and Pb2+ was significantly related to soil organic matter (SOM). Though the soil particle surface was covered by a mixture of organic and mineral components, a two-site distribution could be identified from the titration curves. With the parameters derived from the back-titration and adsorption data, the MICA-Donnan model reasonably predicted the surface complexation of proton and metals. Furthermore, the statistically significant relationships between the model parameters and soil organic matter supported the assumptions in this thesis: (1) Organic matter was the most important sorbent on the particle surface; (2) The MICA-Donnan model may be used to interpret the surface binding data in these soils.
24
Kuroiwa, Kirk D. "The identification of indigenous vegetation capable of survival in lead-contaminated environments." Virtual Press, 2001. http://liblink.bsu.edu/uhtbin/catkey/1221308.
Повний текст джерелаАнотація:
Evaluation of heavy metal accumulation in soils and plants is of environmental importance due to their health effects on humans and other biota. Phytoremediation is an emerging technology that can stabilize or remove heavy metals in soil utilizing metal tolerant plant species (metallophytes). The objectives of this study were to: (1) assess a Superfund site, and a lead-acid battery dump for concentrations of soil lead (Pb) and cadmium (Cd); (2) assess the various chemical fractions of Pb and Cd at both sites; (3) identify native herbaceous vegetation surviving in the contaminated soils; and (4) evaluate plant uptake of Pb and Cd. Soil Pb and Cd concentrations at the Superfund site averaged 55,480 and 8.5 mg/kg, respectively. Soil Pb at the Superfund site occurred primarily in the carbonate, sulfide/residual, and organic chemical fractions (41.6, 28.6, and 26.7, respectively). Soil Pb and Cd concentrations at the dump site averaged 29,400 and 3.9 mg/kg, respectively. Soil Pb occurred mostly in the organic and carbonate fractions as 48.5 and 42.5% respectively. Plant uptake of Pb at both sites ranged from non-detectable (Agrostemma githago, Plantago rugeli, Alliaria officinalis shoots), to 1800 mg/kg (Agrostemma githago root). Cd uptake was maximal in Taraxacum officinale at 15.4 mg/kg (Superfund site). In the majority of plants studied, root Pb and Cd content was higher than for shoots (>_65%). Tissue and soil fractions yielded r2 of 0.61 and 0.57 for the soluble and carbonate-Pb fractions, respectively. The plants with the greatest tissue concentrations of Pb and Cd were predominantly herbaceous species, some of which produce sufficient biomass to be practical for phytoremediation technologies.Department of Natural Resources and Environmental Management
25
Shi, Xianzhong. "Hyperspectral sensing of acid sulphate soils and their environmental impacts in South Yunderup, Western Australia." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/1820.
Повний текст джерелаАнотація:
Several sources of hyperspectral data were used to map the occurrence and spread of acid sulfate soils (AAS). Surface evolution of mineralogy during controlled oxidation of sulphidic material showed the formation of secondary iron minerals linked to soil pH ranges. Spectral characterization, image classification and PLSR of hyperspectral data successfully mapped the occurrence of surface and subsurface acid conditions and related toxicity by linking mineralogy to pH.
26
Tambasco, Giuseppe. "Methods to predict and reduce trace metal levels in lettuce grown on contaminated urban soils." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/MQ44294.pdf.
Повний текст джерела
27
May, John R. (John Robert) 1978. "Sustainability of electricity generation using Australian fossil fuels." Monash University, Dept. of Chemical Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9537.
Повний текст джерела
28
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.
Повний текст джерелаАнотація:
[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.
29
Shin, Mari. "Surfactantligand systems for the simultaneous remediation of soils contaminated with heavy metals and polychlorinated biphenyls." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85096.
Повний текст джерелаАнотація:
Ligand I- along with nonionic surfactant, Triton X-100 or anionic surfactant, sodium dodecyl sulfate (SDS) were applied as soil washing agents to desorb Cd from both naturally and artificially contaminated soils. After seven consecutive washings, up to 90% of Cd was desorbed from both soils. Triton X-100 with I- showed a higher capacity to desorbing Cd than did SDS with I-. The increase of ligand concentration was a critical factor for increasing leaching capacity. Without the ligand, surfactant alone could not desorb Cd effectively from either soil. After seven consecutive washings, a sequential extraction experiment was performed for soil residuals to define the soil fraction of Cd removed by the washing agent. Among the washing agents, only Triton X-100/I- could remove Cd from the exchangeable fraction of both soils.Various ligands including I-, SCN-, and I-/SCN- in combination with Triton X-100 were tested for their efficacy in desorbing heavy metals such as Cd, Zn, Cu, and Pb from a field contaminated soil. Cadmium was preferentially desorbed by Triton X-100/I- whereas Zn and Cu were preferentially desorbed by Triton X-100/SCN-. The mixture of I- and SCN- with Triton X-100 desorbed the most Cd and Cu, but not for Zn, as I- inhibited Zn desorption. Sequential extraction experiments after seven washings showed that metals held in the exchangeable fraction can be desorbed only by a combination of ligand and surfactant.
Nonionic surfactants having different alkyl chain lengths in combination with ligand I- were tested for the desorption of Cd and PCBs from soil. Cadmium desorption was increased at the lower surfactant concentration and higher ligand concentration. The increase in the hydrophilic alkyl chain length of the surfactant adversely affected Cd desorption. Up to 100% of PCBs were successfully removed by most of surfactant-ligand combinations and the desorption was less dependent, compared to heavy metals, on the concentration of washing agents and length of alkyl chain. The linear relationships between number of washings and Cd desorption, and between alkyl chain length and Cd desorption was defined. (Abstract shortened by UMI.)
30
Schlanger, Joshua Lee. "Rates and energetics of organic vapor sorption by soils." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19916.
Повний текст джерела
31
Liberti, Michael F. "Spatial distribution of heavy metals in Center Township, Delaware County surface soils." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1115430.
Повний текст джерелаАнотація:
Numerous urban soils surrounding industrial and metallurgical facilities in the U.S. are contaminated with metals including lead (Pb), cadmium (Cd), copper (Cu), Zinc (Zn), chromium (Cr), and nickel (Ni). Simplified geochemical mapping requires soil sampling and analysis for the presence of heavy metals from a grid pattern within a geographic area. In this study, a contour map of metal concentrations at two depths was subsequently superimposed over a standard political map to indicate areas of elevated metal concentrations in the soil. Natural levels of Pb, Cd, Cu, Zn, Cr, and Ni in Delaware County soils were determined to be 114.2 mg/kg, 0.14 mg/kg, 29.3 mg/kg, 88.4 mg/kg, 9.0 mg/kg, and 39.8 mg/kg, respectively. The average concentrations of metals found throughout Muncie, 203.9 mg/kg Pb, 39.2 mg/kg Cu, 275.4 mg/kg Zn, 9.7 mg/kg Cr, and 25.0 mg/kg Ni, were compared with natural levels to determine the extent of heavy metal pollution from atmospheric deposition. From the geographic mapping of metal concentrations, the effect of past industrial processes on possible contamination of soils by metals in Muncie, Indiana, was determined. Metals were also be fractionated in order to assess the percentage which is potentially bioavailable.Department of Natural Resources and Environmental Management
32
Petersen, Morgan L. "Biofilm Formation of Escherichia coli from Surface Soils is Influenced by Variation in Cell Envelope, Iron Metabolism, and Attachment Factor Genes." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28869.
Повний текст джерелаАнотація:
Biofilm formation may increase survival and persistence of Escherichia coli in the highly variable conditions of soil environments, though it remains unknown the extent variation in biofilm formation affects survival. We asked what genetic traits influence biofilm formation in phylogroup D E. coli isolates from surface soils, and are they associated with the soil environment? Biofilm density was analyzed and compared with soil environment characteristics. Isolates produced more biofilm per unit growth at 15°C than 37°C. Biofilm formation was greater in soil isolates than fecal isolates and in soils with moisture and higher calcium and pH levels. A GWAS analysis found variants involved in cell envelope formation and structure were associated with biofilm formed at 37°C, and stress response and iron acquisition variants were associated with biofilm formed at 15°C. Motility variants were associated with a negative effect on biofilm formed and adhesion variants associated with a positive effect.National Science Foundation (NSF) award no. DEB-1453397 to P.W.B.
ND-EPSCoR
33
Wasay, Syed A. "Bioremediation of soils polluted by heavy metals using organic acids." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/NQ44624.pdf.
Повний текст джерела
34
Li, Juan 1963. "Fractionation and speciation of trace metals in contaminated urban soils from Montreal, Canada." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20266.
Повний текст джерелаАнотація:
A variety of extractants were used to fractionate the trace metals Cd, Cu, Mn, Ni, Pb, and Zn in contaminated urban soils. The metals were mostly held in soil solid phases but not in soluble and exchangeable forms. Except for Mn, extractability of metals by selective chemicals was mainly a function of the contamination level. The speciation of these elements in water, 0.01 M CaCl2, and pH-adjusted water extra was calculated using the chemical equilibrium model MINEQL+. The free ions of Cd, Ni, and Zn were the predominant species in most of the water and 0.01 M CaCl2 extracts while PbCO30 was the main form of Pb. Organically complexed Cu accounted for over of the total dissolved Cu. The solubility of trace metals increased as solution pH was decreased. Metals Cd, Ni, Pb and Zn combined with Cl- at low pH (<5). Organically complexed Cu was shifted to Cu2+ when pH was decreased.Except for Mn, the activities of the other metals in water, 0.01 M CaCl 2 extracts, and pH-adjusted water extracts were undersaturated with respect to established minerals in soils. MnHPO4 seems to be controlling the solubility of Mn in these extracts.
35
Bennetts, Helen. "Environmental issues and house design in Australia : images from theory and practice /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phb472.pdf.
Повний текст джерела
36
Sallami, K. "The phytoremediation of heavy metal contaminated roadside soils in Libya by Eucalyptus camaldeulensis." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/163dce75-3b00-41d6-a1b8-5c9cbb896a39/1.
Повний текст джерелаАнотація:
There is a public concern over the potential accumulation of heavy metals in soils. Numerous studies have already demonstrated that areas in close proximity to vehicular traffic are marked noticeably by contamination of soil, air and water. Hence, such activities can affect humans and other living organisms. The aim of this study is to investigate the pollution of soils caused by vehicular traffic, on agricultural land in Azzawiyah, Liby with the view of assessing potential application of phytoremediation options for the remediation of contaminated soils and determine whether soil amendments would improve soil remediation. In an effort to improve the status of pollution of soils by vehicular traffic, a phytoremediation method of remediation of contaminated land has been used in this study, as it is relatively inexpensive and has the potential through the appropriate selection of plant species to be effective. This method is a soil clean up technology that uses the ability of metal accumulator plants to extract metal from contaminated soil with their roots and to concentrate these metals in above-ground plant parts. In this study, the investigation area was in Azzawiyah city where the soil samples and Doedonea viscose plant were collected from the road side. These soil samples were analysed using different experiments to determine physical and chemical properties, such as pH, OM and CEC. Heavy metals in soil and Doedonea viscose shoot and root were analysed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The findings of the study show that all soils samples collected along the highway road connecting Azzawiyah with the southern parts of Libya were found to be granular with a sandy texture. It is also found that the metal content in soil collected from the site, which is close to the roadside was relatively higher than that soil collected from the agricultural field in the same area. Furthermore, the level of Pb (840mg/kg-1) in roadside soils was higher than the natural levels of Pb in soils. In addition, Doedonea viscose plant was not a hyperaccumulor plant. Greenhouse experiments used three plants (E. camaldeulensis, Brassica Juncea and Medicago sativum) to uptake heavy metal, such as Cd, Zn and Pb from the soil samples. The greenhouse experiment results indicate that E. camaldeulensis was the best plant species for phytoremediation of Pb contaminated soils than the other two plants species (Brassica Juncea, Medicago sativum). The efficiency of the E. camaldeulensis was increased by adding amendments (e.g. compost, compost, EDTA, Hoagland solution and Alcaligenes eutrophus) to the plants pots in order to uptake the lead form soil samples. The results of the pots amendments experiments indicate that 15 mmol of EDTA and bacterial inoculums (Alcaligenes eutrophus) were the best amendments to extract lead from the soils. The study suggests that using the Alcaligenes eutrophus with the E. camaldeulensis are more suitable for phytoremediation in terms of accumulation and cost.
37
Nilufar, Fahmida. "Fate and transport of herbicides in soil in the presence of surfactants in irrigation water." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97982.
Повний текст джерелаАнотація:
In many countries around the world, municipal sewage and industrial wastewaters are typically treated, or sometimes only partially treated, prior to their discharge into surface waters. A major anionic surfactant, Linear Alkyl benzene Sulfonate (LAS), and a degraded product of a non-ionic surfactant, Nonylphenol (NP), are frequently found in municipal wastewaters. When wastewater containing such surfactants and their degraded products is used for irrigation, it can have an effect on the sorption/desorption and movement of pesticides in soils. Therefore, a lysimeter study was conducted, in summer 2004, to assess the effect of LAS and NP on the movement of agricultural herbicides through a sandy loam soil. The degradation of the herbicides was studied in lysimeters over a ninety-day period. Irrigation water with a concentration of 12 mg L -1 of LAS and NP was used to assess their effect on the leaching of atrazine, metolachlor, and metribuzin. Moreover, a laboratory sorption experiment was undertaken to estimate the partition coefficients (kd) of the three herbicides with water containing the same concentrations of LAS and NP. Irrigation water containing low concentrations of surfactants (LAS and NP) did not increase leaching of the three herbicides. Therefore, these results would reduce the concerns regarding pesticide leaching through sandy soil brought on by LAS and NP in wastewaters for irrigation, which is becoming more important due to increasing water scarcity in the dry climate regions of the world.Beside the lysimeter study, mathematical models can be used effectively and economically in a very short period of time for simulating herbicide concentrations into soil. PESTFADE, a one dimensional transient flow model, was used, in this study, to simulate the fate of the three herbicides in sandy soils. Another model, Artificial Neural Network (ANN), was also used over mathematical modeling due to its faster execution period and less input parameter requirements, for predicting the concentrations of the three herbicides in a sandy loam soil. The predicted concentrations, from both models were compared with the experimental results from the lysimeter study. Although slight overestimations and underestimations were observed, both models simulated herbicide concentrations in the soil profile satisfactorily.
38
Kamaludeen, Sara Parwin Banu. "Biotic-abiotic transformations of chromium in long-term tannery waste contaminated soils : implications to remediation." Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phk15.pdf.
Повний текст джерелаАнотація:
Bibliography: leaves 166-180. Determines the effect of chromium on the soil microbial community and its activity, the biotic-abiotic mechanisms involved in chromium oxidation, and phytostabilization of chromium using plants and organic amendment in tannery-waste contaminated soil.
39
Leung, Kwun-lun, and 梁冠倫. "Ecological risk analysis of polycyclic aromatic hydrocarbons, black carbon and heavy metals on soils and plants from coal factories inJiyuan City, China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45460516.
Повний текст джерела
40
Man, Yu Bon. "Risk assessment of soils after changing agricultural land use in Hong Kong." HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1227.
Повний текст джерела
41
Smith, Euan. "Chemistry of arsenic in soils of north-east New South Wales /." Adelaide, 1998. http://web4.library.adelaide.edu.au/theses/09ASOP/09asops646.pdf.
Повний текст джерела
42
Choy, Suk-fong, and 蔡淑芳. "Quaternary environmental changes and engineering properties of offshore soils in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245250.
Повний текст джерела
43
Xu, Jun 1969. "A framework for site analysis with emphasis on feng shui and contemporary environmental design principles." Ann Arbor, Mich. : UMI Dissertation Services, 2004. http://scholar.lib.vt.edu/theses/available/etd-10172003-101905.
Повний текст джерелаАнотація:
UMI No. 3110307. "Authorized facsimile, made from the microfilm master copy of the original dissertation." Includes bibliographical references. Summary: This research proposes a new site analysis methodology in the form of an integrated framework. The framework separates the site analysis process into different models, incorporates each model, and considers the interaction between them. The most important models are the environmental models (climate, geology, hydrology, topography, and vegetation models), social-cultural models, economic models, and infrastructure models. Each model also contains several important factors.The study identifies and organizes environmental factors within the framework that influence site analysis and design. Based on the applicability of feng shui principles and their interpretations into measurable factors, this research compares and incorporates feng shui and contemporary environmental design theories, and summarizes essential environmental factors. The emphasis on environmental factors from these models may lead to a better understanding of the relationships between humankind and the natural environment.
44
Juck, David F. "Polyphasic examination of microbial communities in soils contaminated with organic pollutants." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38209.
Повний текст джерелаАнотація:
A polyphasic approach was used to examine the impact of contamination on soil microbial community structure. Two systems were examined using a combined biochemical and molecular biological approach. Petroleum hydrocarbon contaminated soils from two Northern Canadian sites, representing long-term contamination, were examined using Biolog GN plates and PCR-denaturing gradient gel electrophoresis (DGGE) analysis of total community 16S rDNA. Results obtained using both methods demonstrated a positive correlation between samples that was based on the geographical origin of the samples, not on contamination level. In the second system, non-contaminated soil was contaminated with the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to monitor the effect of short- to medium-term contamination. Changes in the soil microbial community were examined using PCR-DGGE of total community 16S rDNA combined with RDX mineralization and chemical analysis of intermediates. The non-contaminated loam soil had an inherent RDX degradative capability and contamination of soil columns with 1000 mg RDX/kg soil did not significantly change the 16S rDNA bacterial community profile. The bacterial diversity remained high as estimated by the number of bands present in the DGGE and by NQ-78704 statistical rarefaction analysis of 16S rDNA clone RFLPs. The same soil, used in 10% soil slurries (w/v), demonstrated two apparently different RDX degradation mechanisms based on mineralization and chemical analysis. The differences were based on aerobic versus anaerobic conditions and the presence/absence of Na3 citrate. PCR-DGGE performed on 16S rDNA from aerobic slurries amended with Na3-citrate detected the stimulation of 3 operational taxonomic units, identified as Stenotrophomonas sp., Sphingomonas sp. and a member of the Alcaligenaceae. The results from the two systems examined (short- to medium-term and long-term contamination) demonstrated the utility of a polyphasic approach in the examina
45
Smith, Euan. "Chemistry of arsenic in soils of north-east New South Wales / by Euan Smith." Thesis, Adelaide, 1998. http://hdl.handle.net/2440/22476.
Повний текст джерелаАнотація:
Bibliography: leaves 137-151.xiii, 151 leaves : ill. ; 30 cm.
Ten soils from northern New South Wales, Australia, were sampled and assessed for their capacity to sorb arsenate (Asv) in relation to soil properties.
Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1998
46
Heppell, Catherine Margaret. "The fate of pesticide in underdrained clay soil." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670237.
Повний текст джерела
47
Graham, Tennille. "Economics of protecting road infrastructure from dryland salinity in Western Australia." University of Western Australia. School of Agricultural and Resource Economics, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0207.
Повний текст джерелаАнотація:
[Truncated abstract] The salinisation of agricultural land, urban infrastructure and natural habitat is a serious and increasing problem in southern Australia. Government funding has been allocated to the problem to attempt to reduce substantial costs associated with degradation of agricultural and non-agricultural assets. Nevertheless, Government funding has been small relative to the size of the problem and therefore expenditure needs to be carefully targeted to interventions that will achieve the greatest net benefits. For intervention to be justified, the level of salinity resulting from private landholder decisions must exceed the level that is optimal from the point of view of society as a whole, and the costs of government intervention must be less than the benefits gained by society. This study aims to identify situations when government intervention is justified to manage dryland salinity that threatens to affect road infrastructure (a public asset). A key gap in the environmental economics literature is research that considers dryland salinity as a pollution that has off-site impacts on public assets. This research developed two hydrological/economic models to achieve this objective. The first was a simple economic model representing external costs from dryland salinity. This model was used to identify those variables that have the biggest impact on the net-benefits possible from government intervention. The second model was a combined hydro/economic model that represents the external costs from dryland salinity on road infrastructure. The hydrological component of the model applied the method of metamodelling to simplify a complex, simulation model to equations that could be easily included in the economic model. The key variables that have the biggest impact on net-benefits of dryland salinity mitigation were the value of the off-site asset and the time lag before the onset of dryland salinity in the absence of intervention. ... In the case study of dryland salinity management in the Date Creek subcatchment of Western Australia, the economics of vegetation-based and engineering strategies were investigated for road infrastructure. In general, the engineering strategies were more economically beneficial than vegetation-based strategies. In the case-study catchment, the cost of dryland salinity affecting roads was low relative to the cost to agricultural land. Nevertheless, some additional change in land management to reduce impacts on roads (beyond the changes justified by agricultural land alone) was found to be optimal in some cases. Reinforcing the results from the simple model, a key factor influencing the economics of dryland salinity management was the urgency of the problem. If costs from dryland salinity were not expected to occur until 30 years or more, the optimal response in the short-term was to do nothing. Overall, the study highlights the need for governments to undertake comprehensive and case-specific analysis before committing resources to the management of dryland salinity affecting roads. There were many scenarios in the modelling analysis where the benefits of interventions would not be sufficient to justify action.
48
Hoyle, Frances Carmen. "The effect of soluble organic carbon substrates, and environmental modulators on soil microbial function and diversity." University of Western Australia. School of Earth and Geographical Sciences, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0050.
Повний текст джерелаАнотація:
[Truncated abstract] The principal aim of this thesis was to examine the response of the microbial community to the addition of small amounts (<50 μg C g-1 soil) of organic C substrates (‘trigger molecules’) to soil. This addition is comparative to indigenous soluble C concentrations for a range of soil types in Western Australia (typically measured between 20 and 55 μg C g-1 soil). Previously it has been reported that the application of trigger molecules to European soils has caused more CO2-C to be evolved (up to six fold) than was applied . . . Findings from this study indicated that there was an additional CO2 release (i.e. greater than the C added) on application of organic C substrates to some soil treatments. However, findings from this study indicate that the response of the microbial community to small additions of soluble C substrate is not consistent for all soil types and may vary due to greater availability of C, and supports the premise that microbial responses vary in a yet to be predicted manner between soil type and ecosystems. Differences in microbial response to the addition of soluble organic C are likely attributable to differences in soil attributes and environmental factors influencing both the diversity of microbes present and the frequency of food events. Theoretically, trigger molecules could also provide a possible control mechanism for microorganisms in arable farming systems. These mechanisms include stimulating either targeted pathogenic microorganisms that starve after depletion of a suitable substrate; or stimulating beneficial microorganisms to manipulate nutrient cycling, by targeting specific functional groups and altering mineralisation and immobilisation turnover rates.
49
Lazenby, Victoria S. "Personal exposure of children to formaldehyde in Perth, Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2010. https://ro.ecu.edu.au/theses/1742.
Повний текст джерелаАнотація:
Formaldehyde is a common air pollutant that tends to be found in elevated concentrations in indoor air. Exposure to formaldehyde has the potential to impact on respiratory health, particularly amongst sensitive individuals and populations, including children. Children spend most of their time indoors at home, however, there are very little data on the contribution of formaldehyde concentrations in homes to personal exposure in children. The principal aim of this cross sectional study was to investigate whether the domestic environment is the most significant source of personal exposure of formaldehyde in children. Forty-one primary school children (aged between 8 and 12) were recruited from two areas of Perth, Western Australia. Each child wore a personal passive formaldehyde sampler over a 24 hour period on two separate occasions, winter and summer. Samplers were also located indoors at home, outdoors at centralised locations and indoors at school for the corresponding period. A questionnaire about lifestyle and behaviour and a daily activity diary were completed for each participant. Passive samplers used filter papers impregnated with 2,4-dinitrophenylhadrazine (DNPH), with formaldehyde detected using high pressure liquid chromatography (HPLC). In winter there was a wide range of personal exposure concentrations, with geometric mean concentrations of 9.7ppb at Duncraig and 11.5ppb at Calista. Indoor geometric mean concentrations at Duncraig were l0.lppb, with outdoor and classroom concentrations below the analytical limit of detection (4ppb). At Calista, mean indoor concentrations were 14.2ppb. The outdoor concentrations were below the limit of detection and school concentrations were 8.0ppb. Summer monitoring occurred during mild meteorological conditions and were very similar to winter results. Geometric mean personal exposure concentrations were 9.2ppb at Duncraig and 8.0ppb at Calista. Indoor geometric mean concentrations at Duncraig were 9.0ppb, with outdoor and classroom concentrations below the limit of detection (4ppb). At Calista, mean indoor concentrations were 9.9ppb, outdoor was below detection limit and school concentrations were l5.2ppb. There were strong correlations between personal exposure and domestic concentrations at both Duncraig and Calista in winter (r2 = 0.73 and 0.88, respectively) and in summer (r2 = 0.67 and 0.84, respectively). The correlation for both seasons combined was significant, with a coefficient of r2 = 0. 78. A time weighted model estimated personal exposure concentrations for each participant using stationary measures in combination with time activity data. These estimates of exposure correlated significantly with measured personal exposure concentrations, with a coefficient of r2 = 0.80 for all data combined. The indoor domestic environment was found to be the most important source of formaldehyde exposure for children. Time weighting was found to provide a stronger estimate of personal exposure than indoor air monitoring alone, although the time weighted model was not a significant improvement over the indoor measure alone.
50
Abraham, Muriel. "Spatial variation in soil organic carbon and stable carbon isotope signature in a pasture and a primary forest in central Panamá." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80159.
Повний текст джерелаАнотація:
Soil properties and their spatial variability was measured to provide a strong database to assess the modification in soil properties associated with future changes in land use. Surface (0--10 cm) soil samples were collected from a 9 ha, 46-year-old pasture being converted to a native tree plantation and a neighboring control pasture near Sardinilla, Panama. A small-scale nested grid of surface soil samples was replicated in the future plantation and a primary forest in the region to evaluate the spatial variability of soil properties. Seven 1 m profiles were sampled in the future plantation and litter samples were collected at the forest and the future plantation.Assuming the three sites were identical before the conversion to pasture, the difference in surface soil organic carbon (SOC) was 0.75 kg m-2 or equivalent to a loss of 0.017 kg m-2 yr -1 since the original land-use change. The control pasture is higher in bulk density but lower in percent SOC than the future plantation, which is critical to future comparisons.
The pasture soils showed signs of soil compaction and of the homogenization of soil properties. For the 7 profiles in the future plantation, total SOC mass ranged from 13.45 to 23.80 kg m-2, and stable isotopes revealed that 82% of the SOC in the top 10 cm is derived from the pasture vegetation, down to 23% at 1 m depth.
Spatially, the full scale of spatial variability was not determined from the nested grids alone. In addition, the 15 x 15 m grid in the future plantation generally over-estimated the semivariance at the scales below 3 m. The nested grids assessed the minimum measurable semivariance below 5 m.
The precision of surface estimations from point observations can be improved by adding a 5 x 5 m grid to any large-scale sampling scheme.