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1
Attanayake, Chammi. "Bioavailability of contaminants in urban soils." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17601.
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Doctor of PhilosophyDepartment of Agronomy
Ganga M. Hettiarachchi
Urban soils may contain harmful levels of potentially toxic contaminants. These contaminants transfer to humans via two exposure pathways: direct transfer (soil-humans by soil ingestion, dermal exposure and inhalation) and food chain transfer (soil-plant-humans). Soil amendments alter the speciation of the contaminants in soils and thereby modify their bioavailability. The objectives of this research were to access the plant availability of lead (Pb), arsenic (As), and polycyclic aromatic hydrocarbons (PAHs); bioaccessibility and speciation of soil Pb, and As; and dermal absorption of soil PAHs in contaminated urban soils; and effectiveness of soil organic amendments on reducing contaminant bioavailability. Two field experiments were conducted in Kansas City, MO and Indianapolis, IN. Both sites had elevated concentrations of Pb in soils (Kansas City site: 30-380 mg kg⁻¹ and Indianapolis site: 200-700 mg kg⁻¹) . Indianapolis site’s soils also had elevated concentrations of As (40-100 mg kg⁻¹) and PAHs (benzo[a]pyrene: 1-10 mg kg⁻¹) . A control treatment (no-compost) and compost-types (leaf compost and/or composted biosolids, non-composted biosolids, mushroom compost) were used as treatments. A leafy vegetable, a fruiting vegetable and a root crop were grown for two growing seasons. The treatments were arranged in split-plot design (main plot factor: compost; sub-plot factor plant-type). An in vitro steady fluid experiment was conducted using human skins to examine the dermal transfer of soil PAHs. The concentrations of Pb, As, and PAHs in the vegetables were low, except Pb in root crops. Compost reduced the bioaccessibility of Pb, but did not change the bioaccessibility of As. Selected soil samples were analyzed for speciation of Pb using extended x-ray absorption fine structure spectroscopy. The predominant Pb species were Pb sorbed to Fe oxy(hydr)oxide and to organic C. Stable Pb phosphates (pyromorphite) was formed during the in vitro extraction. Dermal transfer experiments showed PAHs in the contaminated soils did not transfer through the skin. Stratum conium of the skin acted as a barrier for dermal transfer of soil PAHs. In general, the risk of food chain transfer of soil Pb, As, and PAHs were low in the studied sites and can be further reduced by compost addition. Bioaccessibility of Pb and As in urban soils were low. Dermal absorption of soil PAHs was insignificant.
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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.
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Burgos, Hernández Tania D. "Investigating Soil Quality and Carbon Balance for Ohio State University Soils." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1577141132704637.
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Cook, Nicola. "Bioavailability of trace metals in urban contaminated soils." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/NQ44391.pdf.
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Ljung, Karin. "Metals in urban playground soils : distribution and bioaccessibility /." Uppsala : Dept. of Soil Sciences, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200681.pdf.
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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.
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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.
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Fountain, Michelle T. "Biodiversity of springtails (Insecta : Collembola) in urban soils." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252195.
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Meulemans, Germain. "The lure of pedogenesis : an anthropological foray into making urban soils in contemporary France." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=232635.
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This thesis is an anthropological inquiry into the emergence of urban soils as matters of concern in the worlds of soil scientists and other fields more traditionally involved with cities. Through the lens of soil-making practices, it seeks to elucidate the specificity of urban pedogenesis, including the growth of soils and the lives of the humans associated with them. City soils have typically been neglected in modern thinking about nature and urbanism. They have long been framed solely as a technical question for engineers which seemed to require no further pondering until – in the last two decades – they entered the scope of the soil sciences. This thesis draws on over thirteen months of multi-locale fieldwork conducted in Paris and Lorraine with soil scientists, gardeners and foundation builders. The research does not define a priori what should count as 'urban', 'agricultural' or 'natural' soils. Building on scholarship in anthropology, the soil sciences, science studies, and speculative philosophy, it follows how these actors learn to be affected in the material performance of different relations between people and soils. The chapters are built in counterpoint to one another, occasionally turning to narrative to complement analysis and more traditional ethnography. Each chapter pulls a different diffractive string from the mesh of urban soil matters, and follows where it leads. As ways of knowing that emerge from soil construction are described, the question of what making soils does to knowing them becomes a central thread of the thesis. In this, it looks at how soils participate in apparatuses where they become 'lures for feelings' – affective interweavings in which worlds are experienced.
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Ge, Ying. "Trace metal speciation and bioavailability in urban contaminated soils." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0028/MQ50773.pdf.
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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.
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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.
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Beesley, Luke. "Carbon in urban, brownfield and heavy metal contaminated soils." Thesis, Liverpool John Moores University, 2010. http://researchonline.ljmu.ac.uk/5957/.
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This thesis is comprised of a collection of work on urban, brownfield and heavy metal contaminated soils carried out within the North West of England from March 2007 to December 2009. Field and laboratory based experiments were used to determine the amount of carbon stored in urban soils and fluxes of dissolved organic carbon and soil respiration. The effects of added organic amendments on carbon storage and mobility as well as the onward implications to heavy metals and arsenic mobility and the impact of earthworms on these processes were also investigated. A city-wide topsoil survey of parkland and road verges in Liverpool showed that carbon storage ranged from < 3 to > 10 kg total organic carbon m-2 whilst physico-chemical characteristics and heavy metal and arsenic concentrations also varied considerably. The abundance oftechnogenic material restricted organic carbon storage and flux to the upper 30 cm of an inner city lawn soil studied in greater detail. Brownfield soil carbon storage and fluxes were enhanced by adding a small amount of green waste compost to these soils but large applications did not greatly increase carbon storage further. Enhanced losses of carbon by dissolved organic carbon leaching and increased soil respiration rates were consequences of greenwaste compost additions, although these effects were highly seasonal, occurring in greatest magnitude at the warmest periods of the year. Proportionately, the annual losses of carbon to soil respiration were far greater than those to dissolved organic carbon. An amendment consisting predominantly of woody material and a biochar amendment had a lower impact than composted greenwaste on dissolved organic carbon mobility, and the co-mobilisation of heavy metals and arsenic in a soil from a previously heavily industrialised centre of population. Earthworms reduced dissolved organic carbon when inoculated with compost and biochar amended soil, but increased this soluble fraction of carbon in woody amended soils, with attendant consequence to trace metal and arsenic mobility. Zinc and cadmium mobility were largely independent of changes in soluble carbon, but arsenic, copper and lead were heavily influenced by added carbon. Biochar amendment proved very effective in reducing concentrations of soluble cadmium and zinc in a heavy metal contaminated soil by adsorption, as well as having the added benefit of reducing total and bioavailable polycyclic aromatic hydrocarbon (PAH) concentrations. It is concluded that carbon storage in urban soils can potentially be increased by applying organic amendments, although longer-term carbon storage may only be substantially enhanced with repeated applications of amendments. However, in urban soils with significant residual pollution, it can be questioned whether this practice is environmentally sound, regarding mobilisation of potentially harmful trace elements. Biochar and larger woody fraction amendments to soils may be more efficacious.
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Howorth, António Roman Navarro Stott. "As hortas da área metropolitana de Lisboa: caracterização e fertilidade dos solos." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4204.
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Mestrado em Engenharia Agronómica - Instituto Superior de AgronomiaThe main goal of the present work was to characterize and assess the fertility of Lisbon urban garden´s soils. So, inquiries were made about the main features of the urban gardens and about the producers. Several soil samples were collected from four different sites of the city. After the treatment of the soil samples, the different fertility parameters were analyzed. It was found that the different soils have similar fertility. They presented: concentration values of organic matter higher than 23,58 g/kg soil; average levels of Ca2+ : Mg2+ ratio of 20,14 that can cause magnesium deficiencies in plants; concentrations of available phosphorus and potassium in soil higher than 523,38 mg/kg soil and 275,22 mg/kg respectively. The values of the potential organic nitrogen mineralization certain show a good cycling of organic nitrogen in soil. Despite this similarity in fertility some variations between the different areas were observed. These variations are the result of different cultivation methods used, the agricultural experience of each producer and the main goals that each producer has in this activity. In summary, this study allows urban gardeners to know the state of their soils fertility in order to optimize the future productions, using the best management agricultural practices.
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Menefee, Dorothy. "Anthropogenic influences on soil microbial properties." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32657.
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Master of ScienceDepartment of Agronomy
Ganga M. Hettiarachchi
Human activities have the potential to alter soil biochemical properties in a number of different ways. This thesis will focus on how agricultural practices (tillage and cropping system), climate change, and urban soil pollution (primarily lead and arsenic) affect soil biochemical properties. Two incubation studies were conducted to determine how human activities influence soil biochemical properties. The first study focused on how altered temperature and moisture regimes affected soil properties from four different agroecosystems. Four different soils were incubated under two different soil preparation methods (sieved <4mm and <0.25 mm), three different temperature treatments (12, 24, and 36°C), and two different moisture treatments (field capacity and 80% of field capacity) for 180 days. Destructive samples were taken at 7, 30, 60, 120, and 180 days and the soil microbial community was analyzed using phospholipid fatty acid analysis (PLFA). The second study investigated how soil amendment treatments (Mushroom Compost and Composted Biosolids) of an industrially contaminated site affected the biochemical properties of that soil. Surface soil samples collected 435 days after compost addition from urban garden test plots located adjacent to a former rail yard in Monon, Indiana. Soils were incubated for 30 days to stimulate microbial activity. Following incubation, the soil was analyzed for PLFA, soil enzymes, and available metal fractions. In the first study the greatest differences were found between the <4mm and the <0.25 mm size fractions – which highlights the effect of soil aggregation and structure on microbial populations. After aggregation effects, temperature treatment had the next largest effect on microbial populations, with the greatest biomass in the middle (24°C) treatment. The second study assessed different soil amendments on soil microbial properties and metal availability. Composted biosolids reduced metal availability and increased microbial enzyme activity and biomass.
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Lai, Ying-wai Steve. "A study of urban park soils and user impacts in Hong Kong /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13525281.
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Thesis (M. Phil.)--University of Hong Kong, 1994.Some illustrations are mounted photos. Some illustrations accompanied by transparent guard sheets with outline drawings. Includes bibliographical references (leaves 234-244).
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Benson, Kaitlyn Suzanne. "Assessment of Soil Quality Parameters of Long-Term Biosolids Amended Urban Soils and Dredge Blends." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492601621133386.
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Linde, Mats. "Trace metals in urban soils : Stockholm as a case study /." Uppsala : Dept. of Soil Sciences, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005111.pdf.
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REMBELSKI, MARA KATHLEEN. "URBAN STORMWATER HARVESTING: IMPLICATIONS AND STRATEGIES FOR DETENTION BASIN SOILS." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/618750.
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As the Southwest continues to be impacted by increasing drought stress under changing
climate conditions, innovative water-harvesting strategies will become a necessary dimension of
sustainable water use. The University of Arizona campus has been incorporating waterharvesting
regimes within its urban landscape for over 20 years. This project explores the
physical and geochemical consequences for the surface soils exposed to high volumes of
stormwater discharge and contaminants found in urban runoff. Soil samples were collected from
four different basin sites across the UA campus. These samples were analyzed and compared
using x-ray diffraction, x-ray fluorescence, particle size analysis, and various basic chemical
analyses. The samples were found to vary significantly by their relative type (basin vs. control)
based on pH, LOI, and several geochemical datasets. Soils were most often significantly
different relative to their specific site for geochemical and mineralogical data. Data suggest that
basin properties are most dependent on the age of the basin and the type of runoff received.
Observations also suggest the necessity for soil amendment to improve water and soil quality at
these sites. The application of biochar at the surface of these basins has been studied for the
improvement of local water collection basins.
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Cachada, Anabela Ferreira de Oliveira. "Organic contaminants in urban soils: major inputs and potential risks." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14130.
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Doutoramento em QuímicaUrban soil quality may be severely affected by hydrophobic organic contaminants (HOCs), impairing environmental quality and human health. A comprehensive study was conducted in two contrasting Portuguese urban areas (Lisbon and Viseu) in order to assess the levels and potential risks of these contaminants, to identify sources and study their behaviour in soils. The concentrations of HOCs were related to the size of the city, with much higher contamination levels observed in Lisbon urban area. Source apportionment was performed by studying the HOCs profiles, their relationship with potentially toxic elements and general characteristics of soil using multivariate statistical methods. Lisbon seems to be affected by nearby sources (traffic, industry and incineration processes) whereas in Viseu the atmospheric transport may be playing an important role. In a first tier of risk assessment (RA) it was possible to identify polycyclic aromatic hydrocarbons (PAHs) in Lisbon soils as a potential hazard. The levels of PAHs in street dusts were further studied and allowed to clarify that traffic, tire and pavement debris can be an important source of PAHs to urban soils. Street dusts were also identified as being a potential concern regarding human and environmental health, especially if reaching the nearby aquatic bodies. Geostatistical tools were also used and their usefulness in a RA analysis and urban planning was discussed. In order to obtain a more realistic assessment of risks of HOCs to environment and human health it is important to evaluate their available fraction, which is also the most accessible for organisms. Therefore, a review of the processes involved on the availability of PAHs was performed and the outputs produced by the different chemical methods were evaluated. The suitability of chemical methods to predict bioavailability of PAHs in dissimilar naturally contaminated soils has not been demonstrated, being especially difficult for high molecular weight compounds. No clear relationship between chemical and biological availability was found in this work. Yet, in spite of the very high total concentrations found in some Lisbon soils, both the water soluble fraction and the body residues resulting from bioaccumulation assays were generally very low, which may be due to aging phenomena. It was observed that the percentage of soluble fraction of PAHs in soils was found to be different among compounds and mostly regulated by soil properties. Regarding bioaccumulation assays, although no significant relationship was found between soil properties and bioavailability, it was verified that biota-to-soil bioaccumulation factors were sample dependent rather than compound dependent. In conclusion, once the compounds of potential concern are targeted, then performing a chemical screening as a first tier can be a simple and effective approach to start a RA. However, reliable data is still required to improve the existing models for risk characterization.
A qualidade dos solos urbanos pode ser afetada por contaminantes orgânicos hidrofóbicos (HOCs), prejudicando a saúde ambiental e humana. Este trabalho consistiu em estudar duas áreas urbanas contrastantes (Lisboa e Viseu), com o objetivo de avaliar os níveis de HOCs nos solos e os seus potenciais riscos para a saúde humana e para o ambiente. Pretendia-se ainda identificar as fontes e estudar o comportamento destes contaminantes no solo. Foi possível relacionar as concentrações de HOCs com o tamanho da cidade, sendo os níveis de contaminação muito mais elevados em Lisboa. A identificação das fontes destes contaminantes foi feita através do estudo dos respetivos perfis e da relação com elementos potencialmente tóxicos, utilizando métodos estatísticos multivariados. Lisboa parece ser afetada por fontes próximas (tráfego, indústria e incineração) enquanto em Viseu o transporte atmosférico aparenta ter um papel mais importante. Num primeiro nível da avaliação de risco (RA), foi possível identificar os hidrocarbonetos aromáticos policíclicos (PAHs) nos solos de Lisboa como um perigo potencial. Os níveis de PAHs em poeiras das ruas de Lisboa foram também estudados e permitiram clarificar que o tráfego e os detritos de pneus e de pavimento podem também ser uma importante fonte destes compostos. Utilizaram-se e discutiram-se ferramentas de geoestatística assim como a respetiva utilidade em RA e em planeamento urbano. De modo a obter uma avaliação mais realista dos riscos de HOCs é importante avaliar a fração disponível, que é também a mais acessível para os organismos. Deste modo, foi feita uma avaliação dos processos envolvidos na disponibilidade de PAHs e também dos resultados obtidos pelos diferentes métodos químicos. A adequação dos métodos químicos para prever a biodisponibilidade de PAHs em solos naturalmente contaminados ainda não foi demonstrada, sendo especialmente difícil para os compostos de elevado peso molecular. No presente trabalho também não foi possível estabelecer uma relação significativa entre a disponibilidade química e a biodisponibilidade. No entanto, apesar das elevadas concentrações totais encontradas em alguns solos de Lisboa, tanto a fração solúvel em água como os resíduos acumulados nos ensaios de bioacumulação foram, em geral, muito baixos, o que estará relacionado com os fenómenos de envelhecimento destes contaminantes nos solos. Observou-se que a fração solúvel de PAHs depende do composto em causa e é regulada pelas propriedades do solo. Apesar de não se terem observado correlações entre as propriedades do solo e a biodisponibilidade, observou-se que os fatores de bioacumulação dependem mais da amostra do que do composto. Em conclusão: após a identificação dos contaminantes de interesse uma avaliação química baseada nos teores totais pode ser uma abordagem eficaz no primeiro nível da RA, mas no entanto é necessário melhorar os modelos existentes para a caracterização do risco.
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Mitchell, David Kenneth. "Urban Landscape Management Practices as Tools for Stormwater Mitigation by Trees and Soils." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64799.
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As urban land expands across the globe and impervious surfaces continue to be used for constructing urban infrastructure, stormwater treatment costs and environmental damage from untreated stormwater will rise. Well designed urban landscapes can employ trees and soils to reduce stormwater runoff flowing to streams and treatment facilities. Typical urban soil, however, is compacted and restricts tree growth via high soil strength and inadequate gas exchange. A site preparation method that deeply incorporates compost and includes trees for long term carbon input and pore development was evaluated in the urban setting of Arlington, Virginia. Three species were used in that study of 25 streetside plantings. The site preparation affected soil at 15 30 cm by lowering soil bulk density by 13.3%, and increasing macro-aggregate-associated carbon by 151% compared to control plots, and resulted in 77% greater tree growth during the first year after transplant. In a second experiment, rainfall simulations were used to evaluate common landscape mulch materials for their ability to prevent compaction from traffic as well their affect on surface runoff before and after traffic. When plots were subjected to heavy rainfall, (>97 mm/h) mulches were found to reduce sediment loss 82% and 73% before and after traffic, respectively. Runoff rates from wood chips were only 0.19 ml/s faster after traffic while rates from bare soil and marble gravel with geotextile increased 2.28 and 2.56 ml/s, respectively. Management of soils, trees and landscapes for stormwater benefit could reduce cost of wastewater treatment for municipalities and can prevent environmental degradation.Master of Science
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Thums, Catherine Rosalie. "Geochemical associations and the spatial distribution of metals in urban soils." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/8625.
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Esiana, Benneth O. I. "The long-term dynamics of soil organic carbon in the anthropogenic soils of Scotland's medieval urban landscape." Thesis, University of Stirling, 2015. http://hdl.handle.net/1893/22463.
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In an interdisciplinary study requiring the synergistic association of historical evidence and chemical and biochemical analyses, this thesis investigates the properties and characteristics of historically modified soils known as anthrosols. These soils, developed through the anthropogenic addition of high volumes of organic-rich municipal waste materials to land, including human and animal waste, as part of the waste management practices in medieval urban communities in Scotland at St Andrews, Roxburgh and Elgin, offer an insight to the state and dynamics of these organic material. Soil is one of the most sensitive environmental domains to transformation. These transformations are visible from the alterations to the physical and chemical properties of soil. Anthropogenic activities may leave behind signatures in the soil in the form of artefacts, ecofacts, elemental enrichment or depletion, enhancement in soil magnetic properties and organic matter content. In the historical dimension of this study, the observable features and measurable properties of soil profiles are exploited to reveal past organisation and functions of cultural landscapes by carefully studying the stratigraphic units of soil profile, and examining the association of each unit with settlement artefacts and soil properties. Through comparison with historical records of past events on the respective study sites, the relationship between the soils record of past human activities is observed through physical, chemical and biochemical properties. The historical record is used to assess if such evidence can be used reliably to develop the account of site use for the medieval burghs of Scotland. In the environmental aspect, investigation focuses on the physical and chemical conditions of these soils in terms of their carbon content, composition, residence time estimates and their role in global C cycle and terrestrial carbon budgeting. Past investigations of anthopogenically-deepened soils have been interpreted with respect to historical site use, however, the environmental implications of the resultant accumulated organic material or residue have not previously been considered in much detail. A particular novelty of this aspect of the project is that it is an in-depth examination of anthropogenic soils with known histories extending into the medieval period. This time-depth allows a new understanding of the processes and products of decomposition of known organic materials that were added to soil. The biophysicochemical data obtained from these soils such as their extant organic carbon content and variability with depth, the composition of the various carbon species that together constitute soil organic matter, and biological community and activity (microorganisms and enzymes) provides critical information on the relative recalcitrance, state of decomposition, and the mechanism of stabilisation of these materials in the soil.
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Lai, Ying-wai Steve, and 黎英偉. "A study of urban park soils and user impacts in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31211562.
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Urquhart, Graham John. "Determination and fractionation in urban soils from the city of Glasgow, UK." Thesis, University of Strathclyde, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415371.
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Shetterly, Benjamin James. "Soil Phosphorus Characterization and Vulnerability to Release in Urban Stormwater Bioretention Facilities." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4354.
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Modern urban stormwater infrastructure includes vegetated bioretention facilities (BRFs) that are designed to detain water and pollutants. Phosphorus (P) is a pollutant in stormwater which can be retained in BRF soils in mineral, plant, and microbial pools. We explored soil properties and phosphorus forms in the soils of 16 operational BRFs in Portland, OR. Since soil hydrology can significantly impact P retention, we selected BRFs along an infiltration rate (IR) gradient. We conducted sequential fractionation and tests of P pools and measured P release in a subset of soils after drying and flooding samples for ten days. We hypothesized that mineral or organic soil P forms would be correlated with IR, and that vulnerability to P release would depend on the interaction of drying and flooding treatments with P forms and pools. IR did not significantly explain differences in P forms. Soil TP was elevated across all sites, compared with TP in agriculturally-impacted wetlands and was substantially composed of soil organic matter (OM)-associated P. Phosphorus sorbed to mineral Fe and Al oxides- was variable but positively correlated with water-extractable P. The concentration gradient of water-extractable P was primarily controlled by overall P pools. Experimentally induced P releases were seen in 5 of 6 soils exposed to drying conditions, presumably released through microbial mineralization of OM. Only one site showed significant P release following the flooding treatment. Our measurements supported the idea that Fe and Al oxides provide P sorption capacity in these BRF soils. Variable inputs of P to BRFs through stormwater and litterfall may contribute to variability in P profiles and P release vulnerability across sites. Design specifications and management decisions relating to bioretention soils (e.g. establishment of acceptable soil test P levels, focusing on P forms known to influence vulnerability of P release) may benefit from detailed biogeochemical investigations.
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Golding, Kirsty Ann. "The effect of waste disposal on soils in and around historic small towns." Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/492.
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Soils in the urban environment are distinctive in that they are modified through waste amendments. Consideration has been given to how urban soil properties reflect current human influence; however, recent studies highlight their potential as historical archives. The impact of waste disposal on the nature, properties and formation of urban soils is significant, especially in historic small towns where the extent and complexity of refuse management practices is only just emerging. This study uses a multi-method approach to characterise and understand modes of urban anthrosol formation in three Scottish burghs; Lauder, Pittenweem and Wigtown. The objectives of this study are threefold; to establish the nature and diversity of urban anthrosols in and near to historic small towns, to characterise and account for the multiplicity of urban anthrosols in and near to historic small towns, and to elucidate the processes associated with waste management and disposal in historic small towns. Physical, chemical and micromorphological analysis of topsoil deposits indicate sustained addition of past waste materials to soils within and near to historic small towns. Soil characteristics were heterogeneous across burghs; however, distinct patterns according to past functional zones were identified. The burgh core and burgh acres are important areas of interest at all three burghs. Soil modification was most pronounced within burgh cores resulting in the formation of hortic horizons. Soils within burgh cores are characterised by neutral pH, increased organic matter content, enhanced magnetic susceptibility and elevated elemental concentrations such as calcium, phosphorus and potassium. In comparison the nature and extent of soil modification within burgh acres is more varied. At Lauder hortic soils were identified in the burgh acres suggesting pronounced soil modification through cultivation. Deepened topsoil in the burgh acres at Pittenweem provided evidence for application of mineral rich waste materials in the past. Moreover, magnetic and elemental enhancement (barium, phosphorus, lead, zinc) within the burgh acres south of Wigtown revealed historic soils based anthropogenic signal. It is argued that changes in soil characteristics at Lauder, Pittenweem and Wigtown can be explained through processes of waste management and disposal in the past. Evidence from micromorphological analyses suggests that waste in burgh cores typically comprised domestic waste, animal waste, building materials and fuel residues. These materials were also identified within burgh acres, although it is noted that their abundances were significantly lower. Variation in urban anthrosol characteristics between burghs is attributed to differing industries and patterns of resource exploitation, for example marine waste associated with fishing was only identified in coastal burghs. The sustained addition of waste materials to soils within and near to historic small towns was an effective waste management strategy. Waste disposal in burgh cores was likely to be a combination of direct application and midden spreading in back gardens. This led to enhanced soil fertility which was important in the development of urban horticulture; particularly for poorer inhabitants who did not have access to arable farm land adjacent to the burgh. Dunghills acted as temporary stores of waste in the main thoroughfares of Lauder, Pittenweem and Wigtown. These dunghills were systematically transported to the burgh acres for further use as a fertiliser; hence, an early form of urban composting. Processes of waste disposal could not be deduced from soil characteristics alone; however, likely methods include direct waste deposition, storage and redistribution of midden waste, and storage and redistribution of dunghills. The limitations of soil classification systems and mapping are highlighted, for example urban soils are either omitted from soil maps or are misclassified. It is recommended that urban soils in historic towns should be incorporated into future regional soil maps. Urban soils represent a complex archive of past human behaviour not necessarily reflected in archaeological excavation or documentary analysis. It is argued that soil and artefacts are equally important, hence soil should be a consideration in urban heritage and conservation strategies.
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Ho, Sau-ming Seraphina. "Soil conditions in landscape tree planters in urban Hong Kong /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21375483.
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Carmo, Lúcio Flávio Zancanela do. "Agricultura urbana na cidade de Rio Branco, Acre: caracterização, espacialização e subsídios ao planejamento urbano." Universidade Federal de Viçosa, 2006. http://locus.ufv.br/handle/123456789/5545.
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The fast urbanization of the underdeveloped countries and the exodus field-city increased the ability of the cities to attend this new demand to provide job and appropriate life conditions to growing population. The urban agriculture and around of urban areas shown as a viable activity for the improvement of the quality of life of the urban populations, mainly of the poorest layers. Rio Branco, the capital of the Acre state, is a typical city of the Brazilian Amazon, located inthe Acre river basin, whose formation was influenced to the growth of the extraction and commercialization of the latex. Rio Branco presented an accelerated urban and population growth in last decades, resulting in inefficient urban planning and inequalities in the form of occupation of the urban spaces. The main objective of this study was to elaborate a diagnosis of the use of the soils in the city of Rio Branco, with the approach of the public actions planning that increase or restrict use forms and maximize the family income in the soil conditions and atmosphere of the city in study. As hypothesis, was considered that different patterns from agricultural use of the urban soil in Rio Branco, shows relationship with the process of occupation of the area, with the cultural migrants variations that there fixed, and with the soils types. The soils of the Acre state, as well as of the Rio Branco, presents influenced genesis by sediments of the Andes Cordillera, and most possesses eutrophic characteristics and clay of high activity. Three study sites were selected, distributed in topographic sequence, along the urban area. Inside of each neighbourhood were selected five sampling points, also in topographic sequence. In the materials of soils were accomplished physical, chemical, mineralogical and heavy-metals analysis. After that was elaborated a land use cover and the soil types mapping, with subsequent geoprocessing operations, for example, crossing different maps, for the three studied neighbourhoods. The Plates neighbourhood is located in the highest part and has better soil drainage. This site presented most appropriate land use than the others neighbourhoods, Jardim Primavera and New City. That last neighbourhood presented the worst land use conditions, with few areas of arboreal vegetation and great impermeable areas and exposed soil. In general, all the soils along the topographic sequence have eutrophic characteristics and rich in nutrients, except in only one point located in the Jardim Primavera neighbourhood. All of the soil types are influenced by the freatic surface, for now in a more outstanding way, as in the gleic and fluvic soils, now minus, as in the plintita soils. In general, the soils did not present nutritional restrictions, and they were shown capable to the agricultural use. In many of the sample points, anthropogenic contributions was verified, with anomalous tenors of P, K, Ca, Mg and some micronutrients, as Fe, Zn and Cu, besides the presence of dumps and dejections. The largest restrictions to the agricultural use of the studied urban soils were: the height and variation of the freatic surface and the fragmentation and use of the urban lots.
A rápida urbanização dos países subdesenvolvidos e o êxodo campocidade aumentaram a necessidade das cidades de prover emprego e condições de vida adequadas à crescente população. A agricultura urbana e periurbana (AUP) mostra-se como uma atividade viável para a melhoria da qualidade de vida das populações urbanas, principalmente das camadas mais pobres. Rio Branco, capital do estado do Acre, é uma cidade típica da Amazônia brasileira, situada na bacia do rio Acre, cuja formação foi atrelada ao crescimento da extração e comercialização da borracha. Rio Branco apresentou crescimento urbano e populacional acelerado nas ultimas décadas, resultando em falta de planejamento urbano e desigualdades na forma de ocupação dos espaços urbanos. O principal objetivo deste estudo foi elaborar um diagnóstico do uso dos solos na cidade de Rio Branco, com vista ao planejamento de ações públicas que incrementem ou restrinjam formas de uso e maximizem a renda familiar nas condições de solo e ambiente da cidade em estudo. Como hipótese, considerou-se que padrões distintos de uso agrícola do solo urbano em Rio Branco mostram estreita relação com o processo de ocupação da região, com variações culturais dos migrantes que ali se instalaram, e com os tipos de solos. Os solos do estado do Acre, bem como de Rio Branco, apresentam gênese influenciada por sedimentos da Cordilheira dos Andes, e a maior parte possui caráter eutrófico e argila de atividade alta. Foram selecionados três bairros de estudo, distribuídos em toposequência, ao longo do sítio urbano. Dentro de cada bairro selecionaram-se cinco pontos de amostragem, também em toposequência. Nos materiais de solos foram realizadas análises físicas, químicas, mineralógicas e de elementos-traços. Realizou-se o mapeamento de uso e cobertura do solo e das classes de solo, com posterior cruzamento destes mapas, para os três bairros estudados. O bairro de Placas, localizado na parte mais alta e com melhor drenagem, apresentou um parcelamento e uso do solo mais adequados que os bairros Jardim Primavera e Cidade Nova. Esse último bairro apresentou as piores condições de parcelamento e uso do solo, com poucas áreas de vegetação arbórea e grandes áreas impermeabilizadas e em solo exposto. De forma geral, todos os solos ao longo da seqüência altimétrica mostram-se eutróficos e ricos em nutrientes, com exceção de um ponto no bairro Jardim Primavera. Todas as classes de solo são influenciadas pelo lençol freático, ora de forma mais marcante, como nos solos gleicos e flúvicos, ora menos, como nos solos com plintita. Em geral, os solos não apresentaram restrições nutricionais, e mostraram-se aptos ao cultivo agrícola. Em muitos dos pontos amostrados constatou-se aportes antropogênicos, com teores anômalos de P, K, Ca, Mg e alguns micronutrientes, como Fe, Zn e Cu, além da presença de entulhos e dejetos. As maiores restrições ao uso agrícola dos solos urbanos estudados foram: a altura e variação do lençol freático e a fragmentação e uso dos lotes urbanos.
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Minca, Kristen Kathleen. "Using Soil Nutrient Tests and 1M HNO3 to Predict Total and Bioaccessible Pb in Urban Soils." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1325176659.
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Li, Juan. "Fractionation and speciation of trace metals in contaminated urban soils from Montreal, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0005/MQ44205.pdf.
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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.
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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.
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Boyd, Adam Philip. "Drought Resistance Response of Tall Fescue Established in Disturbed Urban Soils Utilizing Biosolids." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/64846.
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Urban soils are typically degraded due to land disturbance. The poor quality physical and chemical properties of the soil can benefit from application of organic amendments. Local sources of such amendments are biosolids, which are treated domestic wastewater sludges. The objective of this experiment was to compare effects of various high quality biosolids-based soil amendments with synthetic fertilizer on the growth and quality of tall fescue (Schedonorus arundinaceus) under two different soil moisture regimes. The research site was a disturbed soil at the Virginia Tech Turfgrass Research Center in Blacksburg, Virginia. The experimental design was a split plot with irrigation regime as the main factor and soil amendments as the split factor. All treatments were arranged in four randomized complete blocks. The study was established in late summer 2013. Soil amendment treatments, applied prior to seeding in September 2013, were: 1) inorganic N, P, K applied according to soil test laboratory recommendations; 2) anaerobically digested, dewatered biosolids to supply agronomic N rate; 3) anaerobically digested, dewatered biosolids blended with sand and sawdust to supply agronomic N rate; 4) anaerobically digested, dewatered biosolids blended with sand and sawdust to supply agronomic P rate; and 5) composted biosolids to supply agronomic N rate. The agronomic N rate for the turfgrass was 224 kg of estimated plant available nitrogen (PAN) ha-1. Inorganic fertilizer was applied to supply annual P and K requirements prior to seeding in late summer, and the N was split into three application timings (September 2013, April 2014, and June 2014). Supplemental fertilizer N to achieve full agronomic N rate was applied to the treatment plots that received the agronomic P rate of blended biosolids-sand-sawdust. The area was seeded on September 13, 2013 with a tall fescue blend at a rate of 488 kg ha-1. Following full tall fescue establishment, in June 2014, two irrigation regimes, consisting of 0% and 80% evapotranspiration replacement every three days, were initiated. The study had three phases denoted as the pre-drought, drought, and recovery phases which started in April and concluded in August of 2014. Turfgrass color and quality, volumetric soil moisture percentage to a 5 cm depth, normalized difference vegetative index (NDVI), clipping yield, and turfgrass N uptake were measured bi-weekly throughout the growing season. During the first May through July 2014 irrigation season, results were that the fertilizer control consistently provided improved responses relative to the biosolids amended treatments. Clipping yield, quality, and NDVI were all significantly greater in the inorganic fertilizer treatment, but volumetric soil moisture percentages were slightly greater in the biosolids treatments. Turfgrass responses appeared to have been associated with plant available nitrogen, which was lower in the biosolids treatments than in the fertilizer treatment. Calculated PAN for the biosolids products was too low to achieve ideal turfgrass growth and quality. Improving the estimated PAN and/or splitting the organic amendment application times should improve the growth and quality of the turfgrass.Master of Science
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Stewart, Lauren R. "Spatial Prediction of Bioavailability and Risk of Lead in Urban Soils to Children." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1369143613.
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Summerville, Kevin M. "Effectiveness of Amendments and Microbial Treatments on Plant Growth in Urban Garden Soils." Youngstown State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1495712379969062.
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Bower, Jennifer. "Speciation, Distribution, Prediction, and Mobility of Lead in Urban Soils: A Multiscale Study." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/715.
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Lead (Pb), a trace metal notorious for its impacts on human health, has achieved worldwide environmental dispersal resulting from centuries of use by human society. The toxicity of Pb is governed largely by its mineral form, which is in turn controlled by pH, localized reactivity and soil processes that differ according to soil type, location and Pb source. Given the context of these localized dependencies, or site specificity, efforts to predict Pb toxicity and refine sustainable remediation techniques are most useful when Pb behavior is constrained and predicted within environments with homogeneous conditions, such as a single soil. I evaluated and predicted the behavior of Pb, a typical anthropogenic contaminant, within a single soil using bioaccessibility testing and predictive geospatial modeling to assess potential impacts and refine sustainable remediation methods. To test the hypothesis that Pb speciation is influenced by competitive sorption processes in soils, I investigated changes in mobility and speciation of Pb upon addition of amendments at multiple scales using flow-through column experiments, soil characterization and synchrotron-based x-ray techniques.
Kriging and cokriging maps provided a successful estimation of background and total Pb, the latter incorporating housing age as a secondary variable to increase model accuracy, though efforts to automate detection of background Pb were complicated by approximation of building extents, and overall heterogeneity of soil Pb concentration gives high error. Acute Pb heterogeneity is observed at the scale of a single site among near-structure samples. At the city-scale, determination of bioaccessibility revealed that bioaccessible and total Pb are well-correlated, to the extent that bioaccessibility may be predicted for the soil underlying Burlington, VT; this information, combined with predictive blood lead level modeling and the CDC's recent establishment of 5 μg kg-1 as a threshold for blood lead toxicity, enabled the establishment of a site-specific revised soil Pb limit of 360 mg kg-1, lower than the EPA's general soil Pb threshold of 400 mg kg-1.
Characterization of leached and unleached soil using scanning electron microscope energy dispersive spectroscopy (SEM-EDS) and microfocused x-ray techniques provided a first look at Pb paint species using synchrotron technologies. Pb was present within paint chips as hydrocerussite, but appeared to weather to anglesite over time. Pb also seemed to act as cation bridge, attracting clay minerals electrostatically and becoming incorporated into heterogeneous soil aggregates. Accessory paint elements are identified in soil and within paint chips and may further complicate these systems. Column experiments, at acidic pH, yielded little evidence of Pb mobility change in response to modification of competitive sorbents. Kinetics of Pb release were driven by pH, with Pb solubilizing at pH of ˜4.9 as column soil acidifies.
This work provides evidence for changes in Pb speciation over time in urban soils impacted by Pb paint, and presents a framework for predictive risk analysis at a local site using experimental and modeling tools. Multiscale observations and analytical results can be used in future efforts to model and refine sustainable remediation solutions within a site-specific context.
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You, Rui. "The occurrence of contaminants in crops grown under organic soil amendments and peri-urban soils: phytotoxicity and human health implications." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671348.
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L’agricultura moderna ha estat buscant contínuament mètodes efectius per satisfer la demanda d’aliments que augmenta exponencialment a nivell mundial. L’aplicació de residus orgànics com a fertilitzants o esmenes de sòl és una mesura molt utilitzada, ja que subministra nutrients de manera eficient i ràpida als cultius. De fet, des de 2015, la Comissió Europea ha proposat un pla d’economia circular que fomenta la utilització de biosòlids. No obstant això, la presència d’una àmplia gamma de contaminants com elements traça (ET), contaminants orgànics i contaminants emergents com antibiòtics (AB) i gens de resistència a antibiòtics (ARG), ha estat descrita en alguns fertilitzants orgànics. Les verdures poden incorporar els contaminants procedents de sòls fertilitzats amb residus orgànics, suposant així una amenaça per a la salut humana. Per aquesta raó, és necessària l’avaluació dels riscos que pot provocar la utilització d’aquests residus orgànics.
Els fertilitzants orgànics més emprats són les deixalles d’origen animal (fems), el compost (fonts vegetals o deixalles d’aliments) i les deixalles urbanes (llots de depuradora i residus domèstics). Actualment, no existeix cap estudi que avaluï la incorporació dels ET i AB per part de les plantes amb aquests tres tipus de fertilitzants orgànics, ni tampoc l’impacte de l’aplicació repetida de fertilitzants orgànics sobre les mateixes parcel·les. A més, aquesta aplicació repetida de llots de depuradora podria resultar en l’acumulació de Zn i Cu als sòls agrícoles, i la seva presència influiria en la incorporació d’altres contaminants.
Així doncs, en aquesta tesi doctoral s’aborden tres aspectes relacionats amb els contaminants en hortalisses en diferents activitats agrícoles: (1) aplicació de diferents dosis de diferents residus orgànics en sòls de cultiu, que té com a objectiu avaluar l’efecte d’aquesta fertilització en la incorporació de ET i AB en l’hortalissa, (2) aplicació reiterada de residus orgànics en sòls de cultiu i seguiment de la concentració de ET en hortalisses durant diferents cicles productius, amb l’objectiu d’avaluar l’impacte de la fertilització orgànica a llarg termini, i (3) aplicació de fangs de depuradora i diferents quantitats de Zn i Cu a sòls, amb l’objectiu d’avaluar l’efecte d’aquests metalls sobre l’acumulació d’altres contaminants com ET, AB i ARG en les hortalisses. A més d’això, en tots els casos s’ha avaluat el risc per a la salut humana associat al consum d’hortalisses.
En àrees periurbanes, el sòl agrícola pot rebre la contaminació potencial de contaminants procedents de sòls fertilitzats amb residus orgànics, però també els contaminants potencials derivats de les activitats urbanes. Aquests contaminants poden influir en el creixement i desenvolupament dels vegetals. En aquesta tesi, també s’ha desenvolupat un mètode simple i ràpid per tal d’avaluar la contaminació de sòls. Per a això, es van utilitzar dos índexs de creixement de plantes (taxa de germinació de llavors i allargament d’arrels en l’etapa inicial) en tres llavors de verdures per avaluar la contaminació química dels sòls en agricultura de proximitat.La agricultura moderna ha estado buscando continuamente métodos efectivos para satisfacer la demanda de alimentos que aumenta exponencialmente a nivel mundial. La aplicación de residuos orgánicos como fertilizante o enmienda de suelo es una medida ampliamente aceptada, ya que suministra nutrientes de manera eficiente y rápida a los cultivos. De hecho, desde 2015, la Comisión Europea ha propuesto un plan de economía circular que fomenta la enmienda del suelo con biosólidos. No obstante, la presencia de una amplia gama de contaminantes como elementos traza (ET), contaminantes orgánicos y contaminantes emergentes como antibióticos (AB) y genes de resistencia a antibióticos (ARG), ha sido reportada en algunos fertilizantes orgánicos. Las verduras pueden incorporar los contaminantes procedentes de suelos fertilizados con residuos orgánicos, amenazando la salud humana. Por esta razón, es necesaria la evaluación de los riesgos que puede provocar la aplicación de estos residuos orgánicos. Los fertilizantes orgánicos más utilizados son los desechos de origen animal (estiércol), el compost (fuentes vegetales o desechos de alimentos) y los desechos urbanos (lodos de depuradora y residuos domésticos). Actualmente, no existe ningún estudio que evalúe la incorporación de ET y AB por parte de las plantas con estos tres tipos de fertilizantes orgánicos, ni tampoco el impacto de la aplicación repetida de fertilizantes orgánicos sobre las mismas parcelas. Además, esta aplicación repetida de lodos de depuradora resultaría en la acumulación de Zn y Cu en el suelo modificado, y su presencia puede influir en la incorporación de otros contaminantes. Por tanto, en esta tesis doctoral se abordan tres aspectos relacionados con los contaminantes en hortalizas en diferentes actividades agrícolas: (1) aplicación de diferentes dosis de distintos residuos orgánicos a suelos de cultivo, que tiene como objetivo evaluar el efecto de esta fertilización en la incorporación de ET y AB en la hortaliza, (2) aplicación reiterada de residuos orgánicos en suelos de cultivo y seguimiento de la concentración de ET en hortalizas durante diferentes ciclos productivos, cuyo objetivo es evaluar el impacto de la fertilización orgánica a largo plazo, y (3) aplicación de lodos de depuradora y diferentes cantidades de Zn y Cu al suelo, con el objetivo de evaluar el efecto de estos metales sobre la acumulación de otros contaminantes como ET, AB y ARG en las hortalizas. Además, en todos los casos se evaluó el riesgo para la salud humana asociado al consumo de hortalizas. En áreas periurbanas, el suelo agrícola puede recibir la contaminación potencial de contaminantes procedentes de suelos fertilizados con residuos orgánicos, pero también los contaminantes potenciales derivados de las actividades urbanas. Estos contaminantes pueden influir en el crecimiento y desarrollo de los vegetales. En esta tesis, también se desarrolló un método simple y rápido para evaluar la contaminación del suelo. Para ello se utilizaron dos índices de crecimiento de plantas (tasa de germinación de semillas y alargamiento de raíces en la etapa inicial) en tres semillas de hortalizas para evaluar la contaminación química del suelo en agricultura de proximidad.
Modern agriculture has been continually searching for effective methods to meet the exponentially increasing food demand. Amending soil with fertilizers has been widely adopted, as it could efficiently and fast supply nutrients to vegetables. Since 2015, the European Commission has proposed a circular economy plan which encourages the soil amendment with biosolids. Nevertheless, the presence of a wide range of contaminants, such as trace elements (TEs), organic pollutants, and emerging pollutants such as antibiotics (ABs) and antibiotic resistance genes (ARGs), has been widely reported in many organic fertilizers. Vegetables can absorb the contaminants from the amended soil, and further threaten human health. For this reason, risk assessment of organic fertilizer applications is necessary. The most commonly used organic fertilizers are animal-based waste (manure), compost (plant sources or food waste), and urban waste (sewage sludge and household waste). Currently, no study evaluates the plant uptake of TEs and ABs under these three organic fertilizers, nor research evaluates the impact of repeated organic fertilization. Additionally, multiple application of sewage sludge might result in the accumulation of Zn and Cu in amended soil, and their presence would influence uptake of other contaminants. Therefore, in this doctoral thesis, three aspects related to the contaminants in vegetable under different agriculture activities are addressed: (1) amending soils with different doses of different organic fertilizers, which aims to assess the impact of organic fertilizers on the occurrence of TEs and ABs in vegetables, (2) repeated amending soil with organic fertilizers and monitoring the variation of TEs concentrations in vegetables of different productive cycles, which aims to assess the impact of long-term organic fertilization, and (3) amending soils with sludge and different amounts of Zn and Cu, which aims to assess the effect of Zn and Cu on the accumulation of TEs, ABs, and ARGs in vegetables. Furthermore, in every case the risk to human health associated with the consumption of vegetables was evaluated. In peri-urban area, the agricultural soil may receive the potential pollution from fertilizer, but also from potential contaminants due to urban activities. Those pollutants would influence the growth and development of vegetables. In this thesis, a simple and rapid method to assess soil pollution was also developed. Here, we use two plant growth indexes (seed germination rate and root elongation at the initial stage) for three vegetable seeds to assess soil chemical contamination on proximity agriculture.
Universitat Autònoma de Barcelona. Programa de Doctorat en Ciència i Tecnologia Ambientals
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Alvarez-Campos, Odiney Maria. "Assessment of Exceptional Quality Biosolids for Urban Agriculture." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/88745.
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Biosolids have been used as soil conditioners and fertilizers in agriculture and mine land reclamation, but application of Exceptional Quality (EQ) biosolids to rehabilitate anthropogenic soils for urban agriculture is recent and requires greater study to ensure their appropriate use. The objectives were: 1) to quantify plant available nitrogen (PAN) of new EQ biosolids in a greenhouse bioassay; 2) to quantify PAN of EQ biosolids applied to an urban degraded subsoil via tall fescue N fertilizer equivalency, and compare field results to laboratory tests; 3) to investigate EQ biosolids and inorganic fertilizer effects on urban soil properties, vegetable yields, and potential N and phosphorus (P) loss. Biosolids evaluated were products of thermal hydrolysis plus anaerobic digestion (BLOOM), blending with woody mulch (BM) and sand/sawdust (BSS), composting (LBC), and heat-drying (OCB). Organic N mineralization of new blended biosolids products ranged between 20-25% in the greenhouse bioassay. Products BLOOM, BM, and OCB had the highest organic N mineralization as estimated by the 7-day anaerobic incubation, and this test and soil nitrate-N had the highest correlations with tall fescue N uptake (r=0.49 and r=0.505, respectively). We conducted a two-year field study with four growing seasons (fall 2016-2017 and summer 2017-2018) in an urban disturbed subsoil where EQ biosolids were applied seasonally at agronomic N rates, and yearly at reclamation rates (5x agronomic N). Cabbage yields were greater with reclamation rates (~3.0 kg m-2) and bell pepper yields were greater with BLOOM reclamation rate (~1.0 kg m-2) than with the inorganic fertilizer (1.0 kg m-2 and 0.2 kg m-2, respectively) during second year growing seasons. Soil carbon (C) accumulation (%C remaining in the soil) two years after biosolids additions ranged between 37 to 84%. Soil N availability and mineralization were limited most likely due to lack of residual soil C and N, and high clay content. Nitrogen leaching losses from reclamation rates were not greater than agronomic N rates. Leachate P was below detection during most of the experiment. Despite limiting soil conditions, biosolids amendment at reclamation rates showed greatest potential to increase vegetable yield and improve soil properties after two years of application, while not impairing water quality.Doctor of Philosophy
Exceptional Quality (EQ) biosolids are by-products of wastewater treatment plants that have been processed to destroy pathogens, reduce attraction by disease-spreading organisms (e.g. flies, mosquitoes, rodents, etc.), and limit heavy metal concentrations. These characteristics make EQ biosolids safe for use by home gardeners for growing food crops. There is limited information on optimal recommended rates at which these products should be applied to urban gardens. The purpose of our research was to determine optimum application rates of EQ biosolids to urban gardens based on their essential plant nutrient (esp., nitrogen and phosphorus) availability. We learned that the EQ biosolids we studied are less concentrated in plant available nitrogen and phosphorus than biosolids applied to conventional agricultural fields. This is because we diluted our biosolids with sawdust, sand, and woody mulch to facilitate their storage, handling, and ease of application. We learned that high EQ biosolids application rates reduce soil compaction and increase essential plant nutrient availability and crop yields for agriculture practiced in urban soils. The high application rates of EQ biosolids accomplished such soil-improving and yield-increasing benefits without impairing local water quality.
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Wiesner, Sarah [Verfasser], and Annette [Akademischer Betreuer] Eschenbach. "Observing the impact of soils on local urban climate / Sarah Wiesner. Betreuer: Annette Eschenbach." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2013. http://d-nb.info/1036729303/34.
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Kalinski, Kira [Verfasser]. "Ecosystem services of urban floodplain soils under changing climate and water management / Kira Kalinski." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2021. http://d-nb.info/123705043X/34.
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Lander, Mark S. "Evaluation of selected heavy metal concentrations in soils of an urban stormwater retention basin." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0002831.
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Ho, Sau-ming Seraphina, and 何秀明. "Soil conditions in landscape tree planters in urban Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31222626.
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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.
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Hung, Chui-shan Bonnie, and 洪翠珊. "Human impact on the structure and water status of urban park soils in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226103.
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Cardoso, Raquel Braga da Silva Morais. "The fate of contaminants in urban soils and sediments : novel assessments and implications for risks." Thesis, Manchester Metropolitan University, 2014. http://e-space.mmu.ac.uk/332165/.
Full textAbstract:
Soils and road-deposited sediments (RDS) are ubiquitously present in the urban environment and may act as sinks or sources for potentially harmful elements (PHE), namely trace metals, with possible deleterious human health effects. Their proximity to human populations in urban centres evokes the need to fully characterise the occurrence of PHE and their dynamics within and between these media. This research has provided a detailed characterization of Manchester’s soils and RDS in terms of geochemistry, mineralogy and spatial variability by using the quantification and statistical comparison of the presence of PHE in soils and RDS; and by exploring their spatial, geochemical and mineralogical linkages. Soil and RDS geochemical analysis shows that maximum PHE concentrations are often well above the dataset median values and established guidelines, indicating that contamination is present at many locations especially for Cr (max. soil 1238, RDS 544 mg/kg), Ni (max. soil 148, RDS 82.4 mg/kg), Cu (max. soil 2073, RDS 493 mg/kg), Zn (max. soil 1763, RDS 1325 mg/kg) and Pb (max. soil 2758, RDS 2027 mg/kg). RDS contamination is closely related to the proximity of present-day sources; whereas soil contamination derives mainly from historical sources and the accumulation of trace metals over long periods of time. SEM-EDS analysis of soil and RDS grains reveal the presence of natural and anthropogenic-related grains in different proportions, and the detailed characterization of PHE-bearing grains shows that these, by their morphology of size, are likely to impact human and ecosystem health. In RDS, grain size and speciation analyses provided a further insight on the availability and summer/winter variations of PHE in this media - whereas total extractable concentrations are higher in winter RDS, also due to their generally small grain size, exchangeable and reducible concentrations are higher in summer, when coarse fractions are predominant. Multivariate and spatial statistical analyses reveal that element associations in soils and RDS are diverse and attributed to a plethora of sources (e.g. industry; vehicle-related sources such as automotive electronics, the wear and tear of tyres and car parts, and car servicing and repair businesses; wastewater treatment plants; historical industry and coal-related sources) through the mapping of component scores and the modelling of PHE concentrations by OLS and GWR. These techniques evidence the differences and similarities between element groupings for soils and RDS and are a powerful tool to aid source apportionment. This research has contributed to a better understanding of the complex controls on PHE dynamics in urban systems, adding vital information to the assessment of risks posed by PHE exposure on human health.
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Kang, Katherina A. "Soil Carbon Accumulation in an Urban Ecosystem: Canopy Cover and Management Effects." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703418/.
Full textAbstract:
Black carbon (BC), a stable form of organic carbon (OC), is a byproduct of the incomplete combustion of biomass, biofuels, and fossil fuel. The main objectives of this research are to examine the spatial distribution of OC and BC in urban soil and determine the influence of tree canopy cover and landscape maintenance on soil carbon accumulation. Soil sampling was conducted at 29 sites throughout the City of Denton, Texas, in May 2019. Samples were collected from underneath post oak canopies and in adjacent open areas and were analyzed for total carbon (TC), total organic carbon (TOC), total N (TN), C:N ratio, and BC. Although maintenance levels had no significant effect, TOC was greater underneath trees (5.47%, 5.30 kg/m2) than lawns (3.58%, 4.84 kg/m2) at the surface 0-10 cm. Total nitrogen concentration was also greater underneath trees (0.43%) than lawns (0.31%) at the surface 0-10 cm. Preliminary results for BC were closely correlated to TOC. The lack of difference in C:N ratio between cover types indicates that leaf litter quality may not be the primary driving factor in soil C and N accumulation. Instead, differences in soil properties may be best explained by manual C inputs and greater atmospheric deposition of C and N to soils with tree canopy cover. Identifying patterns and potential drivers of soil OC and BC accumulation is important because soil carbon sequestration not only reduces atmospheric CO2, but also may provide additional pollution mitigation benefits, thereby contributing to a more sustainable urban environment.
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Hansen, Nels Edward. "Amending constructed roadside and urban soils with large volume-based compost applications: effects on water quality." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4743.
Full textAbstract:
Mineral nutrients imported in composted dairy manure (CDM) and municipal
biosolid (CMB) amendments for highway-rights-of-way and urban landscapes can pose
a threat to surface water quality. Treatments were developed to evaluate
recommendations for amending roadside and urban soils with compost at large volumebased
rates. Texas Department of Transportation (TxDOT) recommendations were
evaluated in 2002 and 2003. Municipal recommendations were evaluated in 2004.
Treatments were imposed on 4 by 1.5-m field plots on a constructed soil with an 8.5%
slope. Three TxDOT compost application methods were tested; incorporation at 25% by
volume (CMT), topdressing over vegetation (GUC), and topdressing a 5-cm compost
woodchip mix over bare soil (ECC). In 2003, a 12.5% CMT treatment was substituted
for the GUC, and two contrasting composts were compared. In 2002, soil test
phosphorus (STP) concentrations (mg kg-1) were 291, 360, 410, and 1921 mg kg-1 in the
0 to 5-cm layer of a course textured CMT, fine textured CMT, GUC, and ECC
treatments, respectively using CDM. In 2003, STP concentrations were 264, 439, 496,623, 1115, and 2203 mg kg-1, in the 0 to 5-cm layer after incorporation of CDM and
CMB at the 12.5 and 25% volume-based rates, and topdressing the 5-cm CDM- or
CMB-woodchip mix over bare soil, respectively. In 2004, contrasting CMB products,
relatively low or high in total phosphorus (TP) were incorporated into the soil at 12.5
and 25% by volume, or imported in transplanted sod at the 25% by volume rate. The
STP concentrations were 87, 147, 180, 301, 322, and 544 mg kg-1, respective to the
previously defined treatments. Runoff water from 14, 10, and 8 natural rain events was
used to characterize nutrient and sediment transport in 2002, 2003, and 2004,
respectively. Concentration of TDP in runoff water was highly variable for roadside
treatments across rain events. Mass losses of TDP were similar after CDM or CMB
were incorporated into the soil at 12.5 and 25% by volume. Compost incorporation was
the most effective method for limiting TP loss in runoff. Roadway and urban soils are
expected to contribute greater TP losses as P concentration increases in soils.
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Diallo, Al Hassane [Verfasser], and Gerd [Akademischer Betreuer] Wessolek. "Methods to Determine Preferential Flow in Water Repellent Urban Soils / Al Hassane Diallo. Betreuer: Gerd Wessolek." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2011. http://d-nb.info/1016533551/34.
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Day, Susan D. "Growth and Physiology of Several Urban Tree Species in Soils Disturbed by Construction Fill or Compaction." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/28639.
Full textAbstract:
Experiments were conducted to determine the effects of applying fill soil around existing trees and mechanisms for species tolerance to soil compaction, both common site disturbances in urban forestry. Groups of 22-year-old white oak (Quercus alba) and 13-year-old sweetgum (Liquidambar styraciflua) were subjected to one of three treatments: a control, fill (20 cm of subsoil spread over the root zones), and compacted fill (same as fill soil, but compacted). Additionally, individual trees had tree wells (fill soil pulled away from trunks), or not. After three years, treatments had no consistent effect on tree growth, chlorophyll fluorescence, or soil respiration. However, soil treatments disrupted normal soil moisture patterns at both sites. Roots of white oak grew into fill layers, although overall root growth was not significantly affected by treatment. Sweetgum roots grew very little into fill soils. However, root distribution shifted upward in the original soil under uncompacted fill. Other factors associated with raising the soil grade, such as soil trafficking and root severance, may be largely responsible for the tree decline often attributed to construction fill.
Another experiment investigated the relationship between tolerance of wet soils and the ability to grow in compacted soils. It was hypothesized that tree species tolerant of wet soils would have opportunities for root growth in compacted soil when high soil moisture reduced soil strength. Seedlings of flowering dogwood (Cornus florida), a species intolerant of inundation, and silver maple (Acer saccharinum), a bottomland species, were grown in a loam soil maintained at various combinations of soil strength and soil matric potential. In moderately compacted soil (1.5 g cm-3 bulk density), maple seedlings, but not dogwoods, had greater root growth rate, root length per plant, and ratio of root length to root dry weight in the wet soil (0.006 MPa soil matric potential) than in the moist and dry soils (0.026 and 0.06 MPa, respectively). No such effect was detected in highly compacted soil (1.7 g cm-3). It can be concluded that silver maple roots can grow in moderately compacted soil when high soil water content decreases soil strength, whereas dogwood is unable to take advantage of this opportunity.Ph. D.
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Bartens, Julia. "Trees and Structural Soil as a Stormwater Management System in Urban Settings." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/36081.
Full textAbstract:
Urban runoff continues to impair water quality and there is an increasing need for stormwater management within the limited confines of urban spaces. We propose a system of structural soil and trees that can be incorporated beneath pavement. Structural soil has a high load-bearing capacity yet is engineered to support tree root growth. Stormwater is directed into a structural soil reservoir below the pavement where tree roots can also thrive.
Two container experiments evaluated tree function in this system. We examined whether tree roots can grow into compacted subsoils and if root penetration increases soil infiltration rate. Quercus velutina, Acer rubrum, and a no-tree variant were planted in 26.5 L (7 gal) containers and the rootballs surrounded by compacted clay loam. Roots grew into all layers of the compacted soil. Infiltration rate increased by 63% (+/-2%) compared to no-tree containers. A second experiment evaluated water uptake and tree development in fluctuating water tables. Quercus bicolor and Fraxinus pennsylvanica were planted in 94.6 L (25 gal) containers with structural soils (either Stalite or CU® Structural Soil). Trees were subjected to fluctuating water tables simulating infiltration rates of 2, 1, and 0.1 cm/hr for two growing seasons.
Trees thrived in all infiltration regimes but roots were shallower in slowly drained treatments. Trees grew best and transpired the highest water volume with moderate infiltration. Even if trees uptake only small volumes of water, increased canopy size compared to conventional plantings (because of greater penetrable soil volume) allows greater rainfall interception thus decreasing runoff.
Master of Science
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顔盈曦 and Ying-hei Yuen. "Urban soil pollution by heavy metals in public greenspaces in Hong Kong: profile and particle-fractiondistribution." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31228094.
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Defoe, Phillip Peterson. "Urban brownfields to gardens : minimizing human exposure to lead and arsenic." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17584.
Full textAbstract:
Doctor of PhilosophyDepartment of Agronomy
Ganga M. Hettiarachchi
Urban gardens have been a popular re-use option in the transformation of brownfields—located in older industrialized cities and near peri-urban developments. They provide accessible, available, and affordable supplies of fresh fruits and vegetables, effectively reducing the enigma of “food deserts” across U.S. cities. However, direct (soil ingestion, inhalation) and indirect (soil-plant-human) human exposure concerns about real or perceived trace element contamination in urban soils persist due to previous use. Elevated lead (Pb) and/or arsenic (As) concentrations were found at two (Tacoma and Seattle, WA) urban gardens. The Tacoma site was contaminated with Pb (51 to 312 mg kg-1) and As (39 to 146 mg kg-1), whereas soil Pb at the Seattle site ranged from 506 to 2,022 mg kg-1, and As concentrations were < 20 mg kg-1. Experimental design at both sites was a randomized complete block with a split-plot arrangement (main plots: biosolids/compost vs. non-amended control; sub-plot: plant type). Tacoma site treatment included a Class A biosolids mix (TAGRO) with dolomite. The Seattle site was amended with Cedar-Grove Compost (CGC) plus dolomite. Efficacy of biosolids/compost amendment in reducing Pb and As concentrations was evaluated using root, leafy, and fruit vegetables. Soil Pb and As bioaccessibility were also evaluated. Food chain transfer of Pb and As in vegetables due to surface contamination of produce samples were evaluated on the basis of cleaning procedures. A laboratory incubation study and a controlled greenhouse experiment were conducted on soils collected from the Tacoma site. Effectiveness of addition of laboratory synthesized ferrihydrite (Fh: iron oxyhydroxide) and TAGRO mix, each alone or in combination were screened and tested on the Pb and As co-contaminated Tacoma soil. Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy studies of Pb and As were conducted on incubation study samples to understand treatment-induced Pb- and As-speciation changes. Dilution of soil Pb (10 to 23%) and As (12 to 25%) were observed for biosolids amendment at the Tacoma site, while CGC amendment resulted in 20 to 50% dilution in soil Pb at the Seattle site. Biosolids and CGC amendments reduced Pb concentrations in the vegetables by 50% to 71%. At both sites, Pb concentrations of root vegetables exceeded the MLs established by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). Arsenic concentrations in vegetables were below an estimated ML and were reduced by 46% to 80% when grown on biosolids amended soils. Laboratory cleaning further reduced Pb and As food-chain transfer in vegetables grown in contaminated urban soils. Laboratory incubation and greenhouse studies showed dissolution of Pb in TAGRO plus Fh, and Pb concentrations in Fh amendments were significantly lower than the other amendments. Bioaccessible Pb and As were low. Significant reductions in bioaccessible As were observed when soils were amended with both TAGRO and Fh. X-ray absorption spectroscopy results indicated that chloropyromorphite-like (stable Pb phosphates) phases were the most dominant Pb species. Arsenic existed mainly as As5+, scorodite (FeAsO4•2H2O)-like species in all the treatments ranging from about 60% (control) to about 70% (TAGRO plus ferrihydrite). Amendments utilizing both biosolids and Fh significantly reduce human exposure risks present in urban soils contaminated with Pb and As.