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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Lipid Analysis and Microbial Community Characterization of Subsurface Shale

Trexler, Ryan Vincent 08 August 2017 (has links)
No description available.
12

Uso da abordagem estat?stica procrusteana em Ecologia de Solo: caso de estudo envolvendo sistema de integra??o lavoura-pecu?ria-floresta no Cerrado / Uses of the procrustean statistical approach in soil ecology: a case of study involving an integrated agroecosystem in Brazilian savannah

LISBOA, Francy Junio Gon?alves 25 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-02T21:19:46Z No. of bitstreams: 1 2015 - Francy Junio Gon?alves Lisboa.pdf: 2939884 bytes, checksum: c4aa4152d0d3ca90c85ecb78ff7e5da6 (MD5) / Made available in DSpace on 2017-05-02T21:19:46Z (GMT). No. of bitstreams: 1 2015 - Francy Junio Gon?alves Lisboa.pdf: 2939884 bytes, checksum: c4aa4152d0d3ca90c85ecb78ff7e5da6 (MD5) Previous issue date: 2015-02-25 / CAPES / This thesis is part of a multiple scientific effort seeking to support the replacement of degraded brazilian pastures by systems which integrate different land use types such as crop, pasture, and forest plantation (collectively known as iCLF systems). Here, the focus was also to discuss the potentialities of an unusual statistical multivariate approach called ?Procrustes Analysis? in the plant and soil ecology framework. The current thesis has three chapters through which details of the Procrustes analysis are presented on both technically e intuitively manner. The first chapter describes roadmaps showing how the procrustean residual vector (so-called PAM: Procrustean association metric), representing the multivariate correlation between two or more data tables, can be used as an univariate variable in more user-traditional statistical approaches such as ecological ordination, regression analysis and ANOVA followed by mean comparisons. The second chapter discussed a case study and had as the general objective to use PAMs, depicting the relationships between distance matrices from individual soil microbial structure (PLFA: Phospholipids Fatty Acid) and distance matrices form soil properties variables (chemical and physic), as response variables in an ANOVA framework with land use type as categorical predictor (degraded pasture, improved pasture, native fragment and iCLF system). The hypothesis in this case was that the fungi:bacteria ratio given by PLFA analysis, a good index of changes in microbial structure as response to land use alteration and associated to more conservative soils in terms of carbon mineralization, is favored by the man ? introduced vegetal heterogeneity which characterizes the integration crop ? livestock ? forest. The last chapter was entirely dedicated to answer some technical questions which arose after the publication of the first chapters. Basically the two most common questions were: i) Does the increasing number of columns/variables within a data table affect Procrustes outcomes? ii) Can the procrustean residual vector, the PAM, translate differences between treatments in terms of multivariate correlation as it is used in mean comparisons? Specifically for these questions, Procrustes was useful in supporting iCLF systems as potential alternative to degraded pasture by raising insights that the man ? introduced vegetal heterogeneity in such integrated agroecosystem, favor shifts in microbial structure toward fungal dominance. / A presente tese fez parte do esfor?o multinstitucional buscando sustentar a substitui??o de pastagens degradas por sistemas que integrem diferentes tipos de uso da terra, mais especificamente aqueles integrando lavoura, pastagem, e floresta plantada, coletivamente: sistemas iLPF. Aqui, o foco foi a explora??o das potencialidades da abordagem estat?stica denominada an?lise Procrutes, ou simplesmente Procrustes, na seara de ecologia de planta e solo. Basicamente, a tese foi composta por tr?s cap?tulos onde ? descrito com detalhes os principais nuances dessa abordagem multivariada ainda pouco utilizada por ecologistas de planta e solo. O primeiro cap?tulo descreve roteiros esquem?ticos mostrando como o vetor de res?duos derivado da correla??o e duas tabelas de dados pela an?lise Procrustes (chamado PAM: Procrustes association metric) pode ser utilizado como representante univariado da correla??o em outras abordagens estat?sticas (ordena??o ecol?gica, regress?o, e ANOVA seguida de teste de m?dias). O segundo cap?tulo da tese, utilizando sugest?es do primeiro cap?tulo, tratou de um estudo de caso. Neste caso, fazenda experimental situada no munic?pio de Cachoeira dourada ? GO, e contendo quatro diferentes tipos de uso da terra, dentre os quais um sistema iLPF, foi escolhida para a condu??o do estudo de caso. O objetivo geral foi acessar como correla??es, no formato de PAM, entre tabelas de dados representadas por vari?veis individuais de estrutura microbiana (dada por an?lise de lip?dios oriundos do solo; PLFA: Phospholipids Fatty Acid) e propriedades individuais de qu?mica e f?sica de solo, eram moduladas pelo tipo de uso da terra: pastagem degradada, pastagem melhorada, fragmento de mata nativa, e sistema iLPF. A hip?tese para o estudo de caso foi a de que a rela??o fungo: bact?ria, comumente associada a ambientes mais conservativos, era promovida pelo sistema iLPF uma vez que tais sistemas s?o caracterizados pelo aumento da heterogeneidade vegetal oriunda da sistematizada introdu??o de especies arb?reas em meio a pastagem. O terceiro e ?ltimo cap?tulo da tese foi estritamente dedicado a responder questionamentos t?cnicos referentes ? abordagem procrusteana e surgidos depois das publica??es dos dois primeiros cap?tulos da tese. Neste caso, dois dos questionamentos mais comuns foram abordados. Foram eles: i) quais s?o os efeitos da correla??o entre colunas/vari?veis dentro de uma tabela de dados sobre os resultados da an?lise Procrustes? ii) Pode o vetor de res?duos procrusteanos, a PAM, traduzir diferen?as entre tratamentos em termos da for?a de correla??o multivariada entre duas tabelas de dados? Para o estudo de caso os resultados da corrente tese suportaram os sistemas iLPF como potencial alternativa para substitui??o de pastagens degradadas ao levantar ind?cios de que a heterogeneidade vegetal introduzida nos sistemas iLPF pode favorecer o deslocamento da estrutura microbiana em dire??o ao dom?nio de fungos.
13

Využití analýzy fosfolipidových mastných kyselin při studiu biosušení / Utilization of phospholipid fatty acids analysis for biodrying study

Stránská, Štěpánka January 2019 (has links)
The aim of this thesis is the utilization of phospholipid fatty acids (PLFA) analysis to determine groups of microorganisms present during the biodrying of sewage sludge and their description in relation to the temperature regime of the biodrying. Four experimental cycles A, B, C, D were followed. Cycles A, B and C, D differred from each other in the sewage sludge collected from two waste water treatment plants. The cycles A, B, C and D were each performed in two reactors with different aeration regimes to compare the mesophilic (max. temperature ±50 řC) and thermophilic (max. temperature ±70 řC) regimes of biodrying. PLFA analysis was used to determine the microbial groups. Concentrations of individual PLFA were subjected to principal component analysis (PCA). The total PLFA concentration corresponding to total microbial biomass was decreasing during both temperature regimes of cycles B, C, D, while the total PLFA concentration increased towards the end of both temperature regimes of cycle A. The total PLFA concentration reached statistically higher values at the end of the mesophilic regime of cycles B, C and D. The development of fungi to bacteria ratio showed that fungi applied more with the progression of both temperature regimes of cycles A, B and the thermophilic regime of cycle C. Based on...
14

ENVIRONMENTAL HETEROGENEITY EFFECTS ON DIVERSITY AND NITROUS OXIDE EMISSIONS FROM SOIL IN RESTORED PRAIRIE

Scott, Drew Austin 01 May 2019 (has links)
Ecological theory predicts that high environmental heterogeneity causes high biodiversity. Theory further predicts that more biodiversity results in greater ecosystem functioning. These theoretical predictions were evaluated in three studies using grassland restorations from agriculture.
15

Microbial Growth on Pall-rings : A problem when upgrading biogas with the technique water absorption

Tynell, Åsa January 2005 (has links)
<p>Upgradering av biogas med tekniken vattenabsorption är vanligt i Sverige. Elva biogasanläggningar med tillsammans fjorton uppgraderingsanläggningar använder sig av tekniken. Problem med igensättning av fyllkroppar i absorptionskolonnen, samt i ett fall i desorptionskolonnen är vanligt förekommande och har en negativ effekt på uppgraderingen av rågas till fordonsgas. Fem av de nio anläggningarna i denna studie har problem med mikrobiell tillväxt på fyllkropparna. Syftet med denna rapport var att identifiera den mikrobiella tillväxten och avgöra vilka faktorer som reglerar den för att kunna rådge driftsansvariga hur man motverkar tillväxt.</p><p>En enkät skickades ut och studiebesök gjordes för att samla information om anläggningarna. Fosfolipidfettsyra (PLFA)-analyser utfördes för att bestämma mikrobiell biomassa och de organismer, som kan indikeras av de PLFA som är s.k. biomarkörer.</p><p>Prover samlades in från fyra uppgraderingsanläggningar: Jönköping, Kristianstad, Linköping och Uppsala. Proverna som samlades in var till utseendet olika, allt från gult slem från Linköping till röd-brun gegga som liknade kaffe-sump från Uppsala. I proverna från Linköping och Uppsala detekterades biomarkörer för metanoxiderande bakterier (metanotrofer) av typ I. Metanotrofer finns i jord, vatten och luft i miljöer med tillgång till metan och syre. I Jönköpingsproverna detekterades biomarkörer actinomyceter som är en vanligt förekommande bakterie i avloppsreningsverkens luftningsbassänger. Den mikrobiella tillväxten som samlades in från Kristianstad räckte enbart till ett prov och därför är det resultatet ej tillförlitligt.</p><p>I samtliga prover detekterades svamp (fungi) som förmodligen etablerats efter andra organismer.</p><p>Faktorer som kan anses påverka den mikrobiella tillväxten är processvattnets kvalitet, pH och temperatur. Rent vatten (dricksvatten) innehåller mindre mängd organiskt material, samtliga anläggningar som använder sig av avloppsvatten upplever problem. Lågt pH är gynnsamt för att minska den mikrobiella tillväxten eftersom de flesta organismer trivs bäst vid neutralt pH. Låg temperatur är gynnsam eftersom lösligheten för koldioxid och divätesulfid är större vid lägre temperaturer, vilket gynnar uppgraderingen av biogas.</p> / <p>Upgrading of biogas performed using the technique absorption with water wash is common in Sweden where eleven biogas plants, comprising a total of fourteen upgrading plants use this technique. However problems with microbial growth on the pall-rings in the absorption column, and in one case in the desorption column, have negative impact on upgrading the raw gas to vehicle gas. Five of the nine biogas plants studied here have experienced problems with microbial growth. The objective of this report was to identify the microbial growth and determine possible factors regulating microbial growth in order to give advice to process management.</p><p>A questionnaire was sent out and visits were made to the upgrading plants to collect information about the plants. A phospholipid fatty acid (PLFA) analysis was performed to determine microbial biomass and community structure, for which PLFA biomarkers are one type of indicator.</p><p>Samples were analysed from four upgrading plants: Jönköping, Kristinstad, Linköping and Uppsala. The cultures collected were visually different, varying from yellow and slimy to reddish brown with the consistency of coffee grounds. In the Linköping and Uppsala samples, biomarkers for methane-oxidising bacteria (type I methanotrophs) were detected. Methanotrophs live in environments with access to methane and oxygen and are inhibited by e.g. acetylene. In the Jönköping samples biomarkers indicating the bacteria actinomycetes common in the water of aeration tanks in sewage treatment plants, were detected. In Kristianstad there was only enough culture for one sample, so no reliable result was obtained. Fungi were detected in all samples and probably established after other organisms.</p><p>Factors affecting development of microbial growth were found to be water quality, pH and temperature of the process water. Clean water (drinking water) contains less organic material than cleaned water from sewage treatment plants. All plants using water from sewage treatment plants have experienced microbial growth. Low pH is beneficial for reducing microbial growth since most organisms prefer a neutral environment.</p><p>Low temperature is beneficial for minimising microbial growth since the solubility of carbon dioxide and hydrogen sulphide increases with decreasing temperature.</p>
16

Microbial Growth on Pall-rings : A problem when upgrading biogas with the technique water absorption

Tynell, Åsa January 2005 (has links)
Upgradering av biogas med tekniken vattenabsorption är vanligt i Sverige. Elva biogasanläggningar med tillsammans fjorton uppgraderingsanläggningar använder sig av tekniken. Problem med igensättning av fyllkroppar i absorptionskolonnen, samt i ett fall i desorptionskolonnen är vanligt förekommande och har en negativ effekt på uppgraderingen av rågas till fordonsgas. Fem av de nio anläggningarna i denna studie har problem med mikrobiell tillväxt på fyllkropparna. Syftet med denna rapport var att identifiera den mikrobiella tillväxten och avgöra vilka faktorer som reglerar den för att kunna rådge driftsansvariga hur man motverkar tillväxt. En enkät skickades ut och studiebesök gjordes för att samla information om anläggningarna. Fosfolipidfettsyra (PLFA)-analyser utfördes för att bestämma mikrobiell biomassa och de organismer, som kan indikeras av de PLFA som är s.k. biomarkörer. Prover samlades in från fyra uppgraderingsanläggningar: Jönköping, Kristianstad, Linköping och Uppsala. Proverna som samlades in var till utseendet olika, allt från gult slem från Linköping till röd-brun gegga som liknade kaffe-sump från Uppsala. I proverna från Linköping och Uppsala detekterades biomarkörer för metanoxiderande bakterier (metanotrofer) av typ I. Metanotrofer finns i jord, vatten och luft i miljöer med tillgång till metan och syre. I Jönköpingsproverna detekterades biomarkörer actinomyceter som är en vanligt förekommande bakterie i avloppsreningsverkens luftningsbassänger. Den mikrobiella tillväxten som samlades in från Kristianstad räckte enbart till ett prov och därför är det resultatet ej tillförlitligt. I samtliga prover detekterades svamp (fungi) som förmodligen etablerats efter andra organismer. Faktorer som kan anses påverka den mikrobiella tillväxten är processvattnets kvalitet, pH och temperatur. Rent vatten (dricksvatten) innehåller mindre mängd organiskt material, samtliga anläggningar som använder sig av avloppsvatten upplever problem. Lågt pH är gynnsamt för att minska den mikrobiella tillväxten eftersom de flesta organismer trivs bäst vid neutralt pH. Låg temperatur är gynnsam eftersom lösligheten för koldioxid och divätesulfid är större vid lägre temperaturer, vilket gynnar uppgraderingen av biogas. / Upgrading of biogas performed using the technique absorption with water wash is common in Sweden where eleven biogas plants, comprising a total of fourteen upgrading plants use this technique. However problems with microbial growth on the pall-rings in the absorption column, and in one case in the desorption column, have negative impact on upgrading the raw gas to vehicle gas. Five of the nine biogas plants studied here have experienced problems with microbial growth. The objective of this report was to identify the microbial growth and determine possible factors regulating microbial growth in order to give advice to process management. A questionnaire was sent out and visits were made to the upgrading plants to collect information about the plants. A phospholipid fatty acid (PLFA) analysis was performed to determine microbial biomass and community structure, for which PLFA biomarkers are one type of indicator. Samples were analysed from four upgrading plants: Jönköping, Kristinstad, Linköping and Uppsala. The cultures collected were visually different, varying from yellow and slimy to reddish brown with the consistency of coffee grounds. In the Linköping and Uppsala samples, biomarkers for methane-oxidising bacteria (type I methanotrophs) were detected. Methanotrophs live in environments with access to methane and oxygen and are inhibited by e.g. acetylene. In the Jönköping samples biomarkers indicating the bacteria actinomycetes common in the water of aeration tanks in sewage treatment plants, were detected. In Kristianstad there was only enough culture for one sample, so no reliable result was obtained. Fungi were detected in all samples and probably established after other organisms. Factors affecting development of microbial growth were found to be water quality, pH and temperature of the process water. Clean water (drinking water) contains less organic material than cleaned water from sewage treatment plants. All plants using water from sewage treatment plants have experienced microbial growth. Low pH is beneficial for reducing microbial growth since most organisms prefer a neutral environment. Low temperature is beneficial for minimising microbial growth since the solubility of carbon dioxide and hydrogen sulphide increases with decreasing temperature.
17

Microbial properties of soils: Effects of Management and pedogenesis

Hsiao, Che-Jen January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Charles W. Rice / Gretchen F. Sassenrath / Soil microorganisms are a critical component of ecosystem services provided by soil. Soil management drives soil physical, chemical, and biological properties. Pedogenesis and management interact to change microbial structure and function in the soil profile. Soil microbial properties may vary temporally with crop development and crop species. The objective of this study was to explore the pedogenetic and anthropogenic controls on key soil microbial properties by (i) assessing the profile of a claypan soil under conventional tillage (CT), no-till (NT), and hay meadow (HM); (ii) assessing seasonal changes of soil microbial properties in a corn/winter wheat/soybean rotation under CT and NT; and (iii) assessing vertical changes of soil microbial properties in response to long-term (28 yrs) tillage and mineral and organic fertilization. Selected microbial properties included extracellular enzyme activity, microbial structure as measured by phospholipid fatty acid (PLFA), as well as soil chemical properties. Soil C, enzyme activities, and microbial biomass were greatest in HM soils, followed by NT and then CT in the claypan soil. Wheat in the rotation increased hydrolase activity and bacterial biomass more than corn, while microbial activities were stable during soybean growth. Increased enzyme activities in the claypan layer resulted from the combination of clay-enzyme interaction and impacts from management practices. In a Mollisol soil, an increase in C-acquiring enzyme activity and microbial PLFAs in a buried A horizon was a result of root growth under no-till practice and mineral fertilization. Surprisingly, long-term mineral fertilizer applications had little effect on enzyme activities and microbial biomass. Long-term organic fertilization increased soil C, enzyme activities, and PLFAs but decreased arbuscular mycorrhizal fungi (AMF) throughout the soil profile to a depth of 90 cm. Microbial properties are controlled by crop and soil management at the soil surface and by the interaction of management and pedogenetic properties deeper in the soil profile. Incorporating grasses in the crop rotation may allow nutrients to be extracted from deeper within the soil profile, enhancing the utilization of the entire soil profile and providing additional nutrient resources to cash crops. Incorporating wheat in the crop rotation supports greater microbial activity and biomass after corn harvest, especially in no-till management. Additional research is required to delineate further causative factors impacting enzyme activity in the claypan layer, a finer resolution in soil microbial community at the species level to explore the linkage between ecological function and microbiome structure, and a network analysis for the soil-plant-microbe interactions.
18

From forest to open bog : A status report from a forest-to-open bog-restoration, 8 years later

Hjelm, Axel January 2021 (has links)
Peatlands are associated with a range of ecosystem services such as long-term carbon storage and sequestration, biodiversity, and potential water reservoirs, mitigating floods and droughts. However, in the 20th century, large peatland areas in the northern temperate and boreal regions were drained by ditching, primarily to enhance forest and agricultural production and peat harvesting. Drainage of peatland is associated with a reduction in wet tolerant peatland species, reduced long term carbon sequestration and increased carbon emissions, conflicting with the goals of the Convention on Biological Diversity (CBD) and the Paris Agreement. Today, there is a big ongoing effort from society to rewet and restore drained peatlands in Sweden, but post- restoration monitoring to evaluate success are often scarce. Here, I examine the recovery of a restored drained and afforested bog in Southern Sweden, using a pristine area of the bog as the reference target. The aim was to ascertain to what extend the restoration had succeed and its potential to fully recover. During one year pore water quality, water level and peat surface level were monitored. In the fall peat cores were collected to investigate differences in peat physical and elemental and the microbial biomass and composition. I found that there are still considerable differences between restored and reference area, most marked by the deeper water level in the restored area, but this was not due to a reduced capacity of peat oscillation (i.e. the peats ability to expand and shrink to follow the water table. However, the restoration had raised the water table closer to the surface when compared to other drained areas in Sweden. The study also found considerable higher quantities and higher aromaticity of dissolved organic matter (e.g. DOC) in the porewater of the restored area and an overall lower total amount of microbial biomass with altered community composition, with higher relative amounts’ of fungi and G- negative bacteria’s in the restored area. The nutrient profile in the porewater (inorganic N,P,K) were similar to what was found in the reference area. In conclusion, both the hydrological and porewater chemistry status are currently most likely sufficient for wet-dwelling peat mosses to establish. Here, I argue that the restoration effect is noticeable but complete recovery is yet far away and there is a risk of recession towards afforestation if peat mosses fails to re-establish.
19

Biodegradace nových typů lehčených polyuretanů v různých environmentálně relevantních mikrokosmech / Biodegradation of new types of lightweight polyurethanes in different environmentally-relevant microcosms

Hušek, Pavel January 2020 (has links)
Presented diploma thesis focuses on a new type of lightweight polyurethane foam (PUR), which has been manufactured with the intention of it being biodegradable within currently valid norms on biodegradation of plastic materials. The future use of said polyurethane foam is as carrier for odor repellent to avoid wildlife-vehicle collisions in agriculture landscape, where, after the end of its lifespan it could be left to biodegrade in soil the environment. The examined material, PUR BIO-10, was tested for biodegradability in laboratory microcosms according to standardized method ASTM D5988-03. Biodegradability was tested in two separate soil types - forest soil and agricultural soil, which have been selected with the future use of the material in mind. According to the method biodegradability was measured as mineralization of the material by capturing evolved carbon dioxide. During the first trial the mineralization of polyurethane foam was 10.65 ± 2.54 % in the forest soil and 20.48 ± 9.18 % in the agricultural soil. During the second trial the mineralization was 3.88 ± 3.42 % in the forest soil and 8.96 ± 1.79 % in the agricultural soil. In the second trial the difference between the soils was statistically significant. After the end of the biodegradation experiments the tested material was...
20

Anaerobic oxidation of methane in paddy soil

Fan, Lichao 30 September 2020 (has links)
No description available.

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