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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.
101

Setting Science Based Targets and Adapting Company Operations an Activities

Söderberg, Fanny, Bergkvist, Malin January 2024 (has links)
The requirements on companies' sustainability work are growing due to the increased awareness of greenwashing which has led to an interest in creating sustainability goals that are “science based”. Therefore, this study investigates the possibilities for a company to get verified Science Based Targets (SBTs) through the Science Based Targets initiative (SBTi). By using a qualitative approach with empirical data gathered from a case study of a Small and Medium-sized Enterprise (SME), this paper further provides how such a sustainability change can be managed by adapting company operations and activities. The results show that the requirements for getting verified SBTs differ depending on certain conditions of the applicant company, where SMEs can utilize a simpler and more stripped-down alternative. However, for all companies it is mandatory to do an inventory of their Greenhouse Gas (GHG) emissions and annually report the progress towards the targets. The study further presents some contradictory aspects regarding the credibility of the initiative. It is argued to improve a company's trustworthiness against external stakeholders but at the same time it can be questioned how thoroughly the initiative checks the reporting of emissions. Moreover, the SBTi acts as a driving force for sustainability changes but it can also create misleading pictures of companies and their progress against the targets. Regarding how to adapt a company's operations and activities and manage a sustainability change to reach the targets, the results show that it depends on three factors. These are the size of the company, the level of sustainability integrated in the culture and the company's view of the entire value chain. For SMEs it is presented to be favorable to include collaborations with bigger actors in the industry and learn from these. It is also shown that, regardless of the size, it is beneficial to have a well-integrated sustainability culture and to strive for incremental changes that include the entire company. Above all, the activities in the value chain are proven to be an important aspect to prioritize. Finally, the paper provides some recommendations for further research, both regarding the development of the SBTi and also regarding the theory of change management in relation to sustainability changes.
102

Ecoeficiência em iluminação pública / Eco-efficiency in street lighting

Sanchez Junior, Oswaldo 15 March 2016 (has links)
Na busca por eficiência energética em serviços e produtos de iluminação pública, a maioria das iniciativas concentra-se em procedimentos voltados estritamente à substituição de tecnologias convencionais por outras mais energeticamente eficientes, considerando somente a fase de operação, onde há mais consumo de energia, e o investimento inicial. No entanto, verifica-se que há uma carência de estudos dedicados à análise da sustentabilidade urbana, em particular com o foco na ecoeficiência das iniciativas, em que pese o crescente interesse das empresas por produtos economicamente e ambientalmente sustentáveis. Portanto, a qualidade do serviço de iluminação pública quanto à sua ecoeficiência (componente importante da sustentabilidade urbana) pode ser desenvolvida utilizando-se o pensamento de ciclo de vida de forma simplificada para avaliar tanto economicamente quanto ambientalmente o empreendimento, de modo a viabilizar a comparação de tecnologias, desenvolvimento de projetos e a tomada de decisão para gestores. O objetivo do presente trabalho é propor um modelo analítico que permita, tanto os desenvolvedores de produtos e projetos como a gestores de serviços de Iluminação Pública IP, gerenciar seus recursos para garantir maior ecoeficiência na transição para tecnologias mais avançadas (como o uso de LEDs em produtos), que mitigam os impactos ambientais e o custo desta transição. Como método, utilizou-se uma abordagem qualitativa, se aplicou a técnica de Avaliação de Ciclo de Vida (ACV) para avaliação ambiental e econômica de produtos e instalações para IP baseados na tecnologia convencional e produtos com tecnologia LED. Com isso obteve-se uma medida da ecoeficiência associada a diferentes soluções. Na sequência, as informações foram analisadas, comparadas e um conjunto de parâmetros foi definido para constituir um modelo para tomada de decisão. Em particular, foi dada ênfase à qualidade da iluminação na definição da Unidade Funcional. Todas as fases do ciclo de vida foram analisadas (extração de matérias primas, fabricação de componentes, integração e fabricação de luminárias, manutenção e descarte). Como resultados, foram obtidos critérios mínimos de comparação para instalações de Iluminação Pública a LED; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) em termos de emissões de gases de efeito estufa (CO2 equivalentes) do setor de IP; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) no Custo do Ciclo de Vida de instalações para IP e foi desenvolvido um Modelo de Análise para integrar o desempenho econômico ao ambiental (ecoeficiência) de produtos e instalações de IP. / Introduction: in the search for energy efficiency services and street lighting products, most of the initiatives focuses on procedures aimed strictly to the replacement of conventional technologies by more energy efficient ones considering only their use phase. However, it turns out that there is a lack of studies dedicated to analyzing this field with a focus on eco-efficiency initiatives, despite the growing interest of companies by products economically and environmentally sustainable. Therefore, the quality of the street lighting service for their eco-efficiency can be developed using the Life Cycle Assessment (LCA) technique in a systematic and objective manner, in order to facilitate the comparison of technologies, project development and decision making for managers. Objective: To generate an analytical model that allows both product and project developers and managers of street lighting services to manage its resources to ensure greater eco-efficiency in the transition to more advanced technologies (such as the use of LEDs in products) that mitigate the environmental impacts and the cost of this transition. Method: it was applied the LCA for environmental and economic evaluation of products and street lighting facilities based on conventional technology and products with LED technology. Further, the information was analyzed, compared and a set of parameters has been set to provide a model for decision-making. In particular, it was given emphasis to the quality of lighting in the definition of a functional unit. Every stage of the life cycle was analyzed (extraction of raw materials, component manufacturing, integration and manufacturing lighting fixtures, maintenance and disposal). Results: we obtained minimum criteria of comparison for Street Lighting LED installations, identifying the impact of new technologies (such as use of LED technology) in the carbon footprint of the street lighting industry. Besides, we identified the impact of new technologies (such as use of LED technology) in the cost of life cycle of street lighting facilities. Lastly, it was developed an Analysis Model to integrate environmental economic performance (eco-efficiency) products and street lighting facilities.
103

Treibhausgasminderung auf Sandböden: Potenziale in verschiedenen Nutzungssystemen

Klepatzki, Julian 15 December 2017 (has links)
Die Ergebnisse aus den beiden Dauerfeldversuchen verdeutlichen, dass die mineralische N Düngung wie erwartet den größten Einfluss auf die Höhe der THG Emissionen hat. Die höchsten THG Minderungspotenziale zeigten sich folglich in der Reduktion der mineralischen N Düngung, insbesondere wenn die N Düngung oberhalb des standortspezifischen Ertragsoptimums liegt. Die Anpassung der Fruchtfolge kann zur Erhöhung der Bodenkohlenstoff-Vorräte beitragen und letztendlich die THG Emissionen mindern, allerdings bedarf diese These weiterer Untersuchungen. Die Ergebnisse haben weiterhin gezeigt, dass mit dem Aufbau organischer Bodensubstanz durch Stalldung erhebliche Potenziale zur THG-Minderung verbunden sind. Je nach methodischem Ansatz zur Berücksichtigung von Bodenkohlenstoff-Veränderungen ergaben sich allerdings große Unterschiede in den THG-Bilanzen und letztendlich auch in den ermittelten THG-Minderungspotenzialen. Die Entwicklung eines einheitlichen wissenschaftlichen Verfahrens zur Berücksichtigung von Bodenkohlenstoff-Veränderungen wird deshalb empfohlen. Die Ergebnisse aus der Fallstudie haben gezeigt, dass die THG Minderung in der landwirtschaftlichen Praxis eine Veränderung der Ackerflächenverhältnisse erfordert. In diesem Zusammenhang ist der Anbau emissionsintensiver Fruchtarten mit einer intensiven mineralischen N Düngung wie beispielsweise Winterraps zu reduzieren und durch den Anbau emissionsarmer Fruchtarten zu ersetzen. Im untersuchten landwirtschaftlichen Betrieb erwiesen sich Mais mit organischer N Düngung sowie der Anbau von Leguminosen als besonders emissionsarm. In der vorliegenden Arbeit konnte darüber hinaus gezeigt werden, dass ein positiver Beitrag der ackerbaulichen Bodennutzung zur THG Minderung nicht zwangsläufig mit höheren Kosten für den Landwirtschaftsbetrieb verbunden sein muss, wenn bei der betriebswirtschaftlichen Optimierung die THG Emissionen angebauter Fruchtarten berücksichtigt werden. / The aim of this study was to analyze the potential for reducing greenhouse gas (GHG) emissions in different land use systems on sandy soils in the Brandenburg region in Germany, based on two long-term field experiments at Thyrow and Groß Kreutz and an on farm case study. The calculations of the GHG balances are based on the LCA standard and the German emission report guidelines. There is currently no scientific consensus on how soil organic carbon changes are to be included in GHG balances. Therefore, different approaches to include soil organic carbon changes in GHG calculations from long-term field experiments were examined. The results of the long-term field experiments showed that mineral nitrogen fertilization had the greatest influence on GHG emissions. The reduction of mineral nitrogen fertilization consequently showed the biggest GHG reduction potential especially if nitrogen fertilization was above the local level. The adaptation of crop rotations may increase soil organic carbon content and thereby mitigate GHG emissions, but this hypothesis requires further research. An increase of soil organic carbon stocks by organic fertilization was shown for the use of farmyard manure. Although this had a high GHG reduction potential, there were large differences between the analytical approaches. This highlights the need to develop standardized scientific methods for assessing GHG emissions from cropping systems. The results of the case study showed that changing the proportions of different crop species can be used for GHG reduction. In particular, the reduction of crops with high mineral nitrogen demand, e.g. oilseed rape, and the substitution with crops having low GHG emissions is recommended. Maize, receiving high rates of organic fertilizer, as well as legumes showed low GHG emissions on the evaluated farm. Furthermore, this study elaborates the potential economic benefit for agricultural enterprises with regards to the correlation of GHG reduction and an optimized crop rotation.
104

Ecoeficiência em iluminação pública / Eco-efficiency in street lighting

Oswaldo Sanchez Junior 15 March 2016 (has links)
Na busca por eficiência energética em serviços e produtos de iluminação pública, a maioria das iniciativas concentra-se em procedimentos voltados estritamente à substituição de tecnologias convencionais por outras mais energeticamente eficientes, considerando somente a fase de operação, onde há mais consumo de energia, e o investimento inicial. No entanto, verifica-se que há uma carência de estudos dedicados à análise da sustentabilidade urbana, em particular com o foco na ecoeficiência das iniciativas, em que pese o crescente interesse das empresas por produtos economicamente e ambientalmente sustentáveis. Portanto, a qualidade do serviço de iluminação pública quanto à sua ecoeficiência (componente importante da sustentabilidade urbana) pode ser desenvolvida utilizando-se o pensamento de ciclo de vida de forma simplificada para avaliar tanto economicamente quanto ambientalmente o empreendimento, de modo a viabilizar a comparação de tecnologias, desenvolvimento de projetos e a tomada de decisão para gestores. O objetivo do presente trabalho é propor um modelo analítico que permita, tanto os desenvolvedores de produtos e projetos como a gestores de serviços de Iluminação Pública IP, gerenciar seus recursos para garantir maior ecoeficiência na transição para tecnologias mais avançadas (como o uso de LEDs em produtos), que mitigam os impactos ambientais e o custo desta transição. Como método, utilizou-se uma abordagem qualitativa, se aplicou a técnica de Avaliação de Ciclo de Vida (ACV) para avaliação ambiental e econômica de produtos e instalações para IP baseados na tecnologia convencional e produtos com tecnologia LED. Com isso obteve-se uma medida da ecoeficiência associada a diferentes soluções. Na sequência, as informações foram analisadas, comparadas e um conjunto de parâmetros foi definido para constituir um modelo para tomada de decisão. Em particular, foi dada ênfase à qualidade da iluminação na definição da Unidade Funcional. Todas as fases do ciclo de vida foram analisadas (extração de matérias primas, fabricação de componentes, integração e fabricação de luminárias, manutenção e descarte). Como resultados, foram obtidos critérios mínimos de comparação para instalações de Iluminação Pública a LED; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) em termos de emissões de gases de efeito estufa (CO2 equivalentes) do setor de IP; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) no Custo do Ciclo de Vida de instalações para IP e foi desenvolvido um Modelo de Análise para integrar o desempenho econômico ao ambiental (ecoeficiência) de produtos e instalações de IP. / Introduction: in the search for energy efficiency services and street lighting products, most of the initiatives focuses on procedures aimed strictly to the replacement of conventional technologies by more energy efficient ones considering only their use phase. However, it turns out that there is a lack of studies dedicated to analyzing this field with a focus on eco-efficiency initiatives, despite the growing interest of companies by products economically and environmentally sustainable. Therefore, the quality of the street lighting service for their eco-efficiency can be developed using the Life Cycle Assessment (LCA) technique in a systematic and objective manner, in order to facilitate the comparison of technologies, project development and decision making for managers. Objective: To generate an analytical model that allows both product and project developers and managers of street lighting services to manage its resources to ensure greater eco-efficiency in the transition to more advanced technologies (such as the use of LEDs in products) that mitigate the environmental impacts and the cost of this transition. Method: it was applied the LCA for environmental and economic evaluation of products and street lighting facilities based on conventional technology and products with LED technology. Further, the information was analyzed, compared and a set of parameters has been set to provide a model for decision-making. In particular, it was given emphasis to the quality of lighting in the definition of a functional unit. Every stage of the life cycle was analyzed (extraction of raw materials, component manufacturing, integration and manufacturing lighting fixtures, maintenance and disposal). Results: we obtained minimum criteria of comparison for Street Lighting LED installations, identifying the impact of new technologies (such as use of LED technology) in the carbon footprint of the street lighting industry. Besides, we identified the impact of new technologies (such as use of LED technology) in the cost of life cycle of street lighting facilities. Lastly, it was developed an Analysis Model to integrate environmental economic performance (eco-efficiency) products and street lighting facilities.
105

Addressing Climate Change in Research and Innovation Projects. A Tool for Anticipatory Carbon Footprint Calculation

Ligardo Herrera, Iván Elías 03 May 2021 (has links)
[ES] El calentamiento global, y el cambio climático (CC) que produce, es una de las amenazas más globales y urgentes de las que es responsable la humanidad. El desafío de mitigar y adaptarse a la CC, entre otros, es una responsabilidad que ha alcanzado a todas las disciplinas, incluyendo el proceso de investigación e innovación. Durante más de 10 años, y como una forma de abordar estos grandes desafíos de nuestro tiempo, con la intención de fomentar la investigación responsable, la Comisión Europea ha estado promoviendo una temática transversal llamada: "Investigación e innovación responsable (RRI, en sus siglas en inglés)". El objetivo es sacar a la luz los problemas relacionados con la investigación y la innovación, anticipar sus consecuencias y hacer participar a la sociedad en el debate sobre la forma en que la ciencia y la tecnología pueden contribuir a crear el tipo de mundo y de sociedad que deseamos para las generaciones futuras. Esta tesis surge como un puente entre el gran desafío que representa el CC y la demanda por parte de la sociedad de investigación e innovación responsable, abordada en el contexto de la RRI. Los financiadores e impulsores de la investigación y la sociedad en su conjunto esperan que los equipos de investigación e innovación proporcionen resultados socialmente deseables, éticamente aceptables y sostenibles. Por lo tanto, la pregunta general que se responde en esta tesis es: ¿cómo sabe un equipo de investigación, sin ser especialista en evaluación ambiental, si su investigación es responsable de emisiones contribuyentes al cambio climático, y cómo puede incluir medidas para reducir o compensar esas emisiones de gases de efecto invernadero (GEI)? Para responder a esta pregunta, la presente tesis doctoral inicia con la descripción de los principales fundamentos que son centrales en ella: CC y RRI. En lo que respecta al primer concepto, explicamos la importancia y los medios para calcular la contribución al CC, principalmente el enfoque de la Huella de Carbono. En lo que respecta al segundo concepto, se explica la alineación de esta tesis el área clave de la sostenibilidad ambiental de la RRI, sus marcos sustantivos y sus dimensiones de anticipación y reflexividad. Una vez establecidos estos dos fundamentos, el cambio climático se aborda en el contexto de la RRI, revisando la literatura sobre los proyectos y propuestas de la RRI, incluyendo la sostenibilidad ambiental, y el CC en particular. Como resultado, surgieron dos avenidas de investigación, que se desarrollan en las siguientes secciones. Una avenida sobre cómo evaluar la influencia de las partes interesadas en un proyecto de investigación en el contexto de la RRI, desarrollada en el capítulo 3, y una avenida sobre la necesidad de nuevas herramientas basadas en bases de datos de acceso abierto para ayudar a los profesionales a integrar la prevención del CC en sus actividades de I + D. El capítulo 4, presenta el diseño de una novedosa herramienta con un algoritmo didáctico para la medición anticipada de la huella de carbono en los proyectos de investigación e innovación. Esta herramienta permite a los investigadores que no tienen formación en evaluación del impacto ambiental estimar las emisiones de gases de efecto invernadero de sus proyectos de investigación e innovación en las primeras etapas, momento en el que la anticipación y la reflexividad son las dimensiones fundamentales de la RRI. / [CA] L'escalfament global, i el canvi climàtic (CC) que produeix, és una de les amenaces més globals i urgents de les que és responsable la humanitat. El desafiament de mitigar i adaptar-se a la CC, entre d'altres, és una responsabilitat que ha arribat a totes les disciplines, incloent el procés de recerca i innovació. Durant més de 10 anys, i com una forma d'abordar aquests grans desafiaments del nostre temps, amb la intenció de fomentar la investigació responsable, la Comissió Europea ha estat promovent una temàtica transversal anomenada: "Recerca i innovació responsable (RRI, en seves sigles en anglès)". L'objectiu és treure a la llum els problemes relacionats amb la investigació i la innovació, anticipar les seves conseqüències i fer participar la societat en el debat sobre la forma en què la ciència i la tecnologia poden contribuir a crear el tipus de món i de societat que desitgem per a les generacions futures. Aquesta tesi sorgeix com un pont entre el gran desafiament que representa el CC i la demanda per part de la societat d'investigació i innovació responsable, abordada en el context de la RRI. Els finançadors i impulsors de la investigació i la societat en el seu conjunt esperen que els equips de recerca i innovació proporcionin resultats socialment desitjables, èticament acceptables i sostenibles. Per tant, la pregunta general que respon a aquesta tesi és: com sap un equip d'investigació, sense ser especialista en avaluació ambiental, si la seva investigació és responsable d'emissions contribuents a el canvi climàtic, i com pot incloure mesures per reduir o compensar aquestes emissions de gasos d'efecte hivernacle (GEH)? Per respondre a aquesta pregunta, la present tesi doctoral s'inicia amb la descripció dels principals fonaments que són centrals en ella CC i RRI. Pel que fa a el primer concepte, expliquem la importància i els mitjans per calcular la contribució a l'CC, principalment l'enfocament de la Petjada de Carboni. Pel que fa a el segon concepte, s'explica l'alineació d'aquesta tesi l'àrea clau de la sostenibilitat ambiental de la RRI, els seus marcs substantius i les seves dimensions d'anticipació i reflexivitat. Un cop establerts aquests dos fonaments, el canvi climàtic s'aborda en el context de la RRI, revisant la literatura sobre els projectes i propostes de la RRI, incloent la sostenibilitat ambiental, i el CC en particular. Com a resultat, van sorgir dues avingudes de recerca, que es desenvolupen en les següents seccions. Una avinguda sobre com avaluar la influència de les parts interessades en un projecte d'investigació en el context de la RRI, desenvolupada en el capítol 3, i una avinguda sobre la necessitat de noves eines basades en bases de dades d'accés obert per ajudar els professionals a integrar la prevenció de CC en les seves activitats d'R + d. El capítol 4, presenta el disseny d'una nova eina amb un algoritme didàctic per al mesurament anticipada de la petjada de carboni en els projectes de recerca i innovació. Aquesta eina permet als investigadors que no tenen formació en avaluació de l'impacte ambiental estimar les emissions de gasos d'efecte hivernacle dels seus projectes de recerca i innovació en les primeres etapes, moment en el qual l'anticipació i la reflexivitat són les dimensions fonamentals de la RRI. / [EN] Global Warming, and the climate change (CC) it produces, is one of the most global and urgent threats humankinds is responsible for. The challenge of mitigating and adapting to CC, among others, is a responsibility that has reached all disciplines, including the research and innovation (R&I) process. For more than 10 years, and as a way to tackle these great challenges of our time, with the intention of fostering responsible research, the European Commission has been promoting a cross-cutting issue named: "Responsible Research and Innovation (RRI)". The aim is to bring the problems (such as research integrity, non-inclusion of stakeholders, application of ethical or sustainability principles, etc.,.) related to R&I to light, to anticipate the possible consequences of R&I process and outcomes, and to engage society in the discussion of how science and technology can help create the kind of world and society we want for generations to come. This thesis emerges as a bridge between the great challenge represented by CC and the demand for responsibility from R&I process and outcomes, addressed in the context of RRI. Research funders and society as a whole claim that R&I teams must provide socially desirable, ethically acceptable, and sustainable outcomes. Hence, the general question to be answered in this thesis is: how does a research team, while not being specialists, know if its research is responsible for relevant contributions to CC, and how can they include measures to reduce or compensate such contributions (Greenhouse Gas emissions, GHG)? To respond to this question, the present dissertation begins with the main foundations that are central to it: CC and RRI. As regards the former concept, we explain the importance and means to calculate the contribution of GHG to CC, mainly the carbon footprint approach. In addition, regarding the latter, how this thesis aligns with the key RRIs' area of environmental sustainability, its substantive frameworks and its anticipation and reflexivity dimensions. Once these two foundations are established, CC is addressed in the context of RRI, reviewing the literature on RRI projects and proposals, which include environmental sustainability, and CC in particular. As a result, two avenues of research arise, which are developed in the following sections. An avenue about how to assess the stakeholders' influence in a research project within the context of RRI, which is developed in chapter 3, and an avenue about the need for new tools based on open-access databases to help practitioners to integrate CC prevention in their R&I activities. Chapter 4 presents the design of a novel tool with a didactic algorithm for anticipatory carbon footprint measuring in R&I projects. This tool allows researchers who are untrained in environmental impact assessment to estimate the greenhouse gas emissions of their R&I projects at early stages, when anticipation and reflexivity are the core RRI dimensions. / Ligardo Herrera, IE. (2021). Addressing Climate Change in Research and Innovation Projects. A Tool for Anticipatory Carbon Footprint Calculation [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165867 / TESIS
106

Estimation of N2O and CO2 emissions from organic and N fertilizers by coupling field measurements with modelling analysis

CHIAZZESE, MURJAL 28 May 2015 (has links)
L'effetto dei gas serra sul cambiamento climatico ha portato molti esperti a considerare la riduzione delle emissioni di gas serra come strategia per il riscaldamento globale. In particolare tale fenomeno è causato dall’anidride carbonica (CO2), metano (CH4) e il protossido di azoto (N2O). E 'ampiamente accettato che la principale fonte antropica di gas a effetto serra (tranne CO2) è dovuta alle attività agricole. Lo scopo di questo studio è quello di definire concetti e strumenti per facilitare il settore agricolo a ridurre le emissioni di gas serra. In particolare, abbiamo posto la nostra attenzione ai sistemi di misurazione delle emissioni dal suolo, testando un nuovo sistema (SASSFlux) e le sue caratteristiche a confronto con due strumenti ampiamente utilizzati (Bruel & Kjaer e gascromatografia). Inoltre abbiamo testato due modelli di simulazione (DNDC e SPACSYS) valutando i dati simulati e quelli misurati su un esperimento effettuato su lisimetri. In fine abbiamo applicato le conoscenze acquisite in pieno campo per la valutazione delle emissioni di CO2 e N2O con diversi concimi e lavorazione del terreno. La tesi si propone di fornire una visione completa dei diversi aspetti da affrontare nella valutazione delle emissioni di gas serra provenienti da diversi scenari di gestione agricola. / The effect of greenhouse gases (GHG) on climate change led many experts to consider the reduction of GHGs emissions as a crucial strategy to tackle the predicted global warming. In particular, atmospheric warming is caused mainly by carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). It is widely accepted that the main anthropogenic source of GHG (except CO2) is due to agriculture activities. The purpose of this study was to help define concepts and tools to facilitate agricultural sector to reduce greenhouse gas emissions. In particular we based our focus on measuring systems for CO2 emissions, testing the performance of novel system (SASSFlux) and its features in different condition with two widely used instruments (Bruel&Kjaer and gas chromatography). Moreover we testing two process-based models, DNDC and SPACSYS, evaluating their performance and the agreement between simulated and measured data on a experiment carried out on lysimeters. At the end we applied all the knowledge acquired on a field experiment evaluating CO2 and N2O emissions from different organic and mineral fertilizers and tillage. The complete thesis aims to provide a comprehensive view of the different aspects to be addressed in the assessment of GHG emissions from different scenarios of agricultural management.
107

Earthworms In Vermont Forest Soils: A Study Of Nutrient, Carbon, Nitrogen And Native Plant Responses

Melnichuk, Ryan 01 January 2016 (has links)
Anthropogenic activities surrounding horticulture, agriculture and recreation have increased dispersal of invasive earthworms. The introduction of earthworms initiates many physical and chemical alterations in forest soils previously unoccupied by earthworms. Three trials were performed to assess the effects of earthworms on soil-water dynamics, C and N and defensive/storage compound production by a native plant. The first trial was a greenhouse experiment, performed to assess the impact of two ecologically contrasting invasive earthworm species on percolate and evaporative soil water loss. Mesocosms were constructed to simulate a typical forest Entisol commonly penetrated by the species of interest, Lumbricus terrestris and Amynthas agrestis. Earthworms were added in pair and combination to replicate an average population density observed in Vermont. Percolate water was collected and evaporative water loss balance was recorded over a period of 140 days. C and N were quantified in A-horizon bulk and aggregate soil as well as the subsoil. Residual surface leaf litter was also quantified. Results indicated significantly increased evaporative water loss where either worm was present. Conversely, percolate water loss was significantly reduced in presence L. terrestris alone. C and N analysis revealed that only L. terrestris had a significant effect on aggregate soil C. While the abundance of many herbaceous species is reduced at invasive earthworm sites, Arisaema triphyllum anecdotally have greater densities where earthworms are present. It has been hypothesized that the greater density is caused by a trait that allows this plant to store Ca, often observed at increased concentrations in earthworm invaded soils as Ca-oxalate Here, we tested the hypothesis that oxalate increases in A. triphyllum when earthworms are present. As such, we conducted a two-way factorial greenhouse trial to test whether the changes to soil properties made by two invasive earthworm species (Amynthas agrestis and Lumbricus rubellus) or their physical presence (and bioturbation) had an effect on the plant production of oxalate. Upon quantification of variable soluble oxalate in corms after senescence, we found that earthworm presence increased water soluble and total oxalate significantly as well as marginally significantly in the case of HCl soluble oxalate. No significant changes in oxalate concentrations were observed under soil treatments alone. Carbon and nitrogen are found extensively in both terrestrial and atmospheric cycles. A shift in the equilibrium of these elements can suggest a strong interaction between an introduced variable (invasive earthworms in this case) and the abiotic environment. To better understand changes in soil properties with earthworm invasion, a 112-day mesocosm study was undertaken to examine C and N dynamics. Two epi-endogeic invasive earthworm species Lumbricus rubellus and Amynthas agrestis were selected for study. Greenhouse gas production by total mesocosm and soil were monitored. Gas flux measurements on 11 dates indicate both worm species increase CO2 and N2O emitted from mesocosm system as well as soil. Mesocosm total C and N (mass balance) indicate significantly more N but no change in C where earthworms are present. This indicates a disruption of denitrification by earthworm invasion that results in increased N2O emissions. This research is the first to examine these variables in concert and confirms holistic view is essential when examining natural systems.
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Consideration of life cycle energy use and greenhouse gas emissions for improved road infrastructure planning

Miliutenko, Sofiia January 2016 (has links)
Global warming is one of the biggest challenges of our society. The road transport sector is responsible for a big share of Greenhouse Gas (GHG) emissions, which are considered to be the dominant cause of global warming. Although most of those emissions are associated with traffic operation, road infrastructure should not be ignored, as it involves high consumption of energy and materials during a long lifetime. The aim of my research was to contribute to improved road infrastructure planning by developing methods and models to include a life cycle perspective. In order to reach the aim, GHG emissions and energy use at different life cycle stages of road infrastructure were assessed in three case studies using Life Cycle Assessment (LCA). These case studies were also used for development of methodology for LCA of road infrastructure. I have also investigated the coupling of LCA with Geographic Information Systems (GIS) and the possibility to integrate LCA into Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA). The results of the first case study indicated that operation of the tunnel (mainly, lighting and ventilation) has the largest contribution in terms of energy use and GHG emissions throughout its life cycle. The second case study identified the main hotspots and compared two methods for asphalt recycling and asphalt reuse. The results of the third case study indicated that due to the dominant contribution of traffic to the total impact of the road transport system, the difference in road length plays a major role in choice of road alternatives during early planning of road infrastructure. However, infrastructure should not be neglected, especially in the case of similar lengths of road alternatives, for roads with low volumes of traffic or when they include bridges or tunnels. This thesis contributed in terms of foreground and background data collection for further LCA studies of road infrastructure. Preliminary Bill of Quantities (BOQ) was identified and used as a source for site-specific data collection. A new approach was developed and tested for using geological data in a GIS environment as a data source on earthworks for LCA. Moreover, this thesis demonstrated three possible ways for integrating LCA in early stages of road infrastructure planning. / <p>QC 20160329</p>
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Sustainable strawberry production and management including control of strawberry powdery mildew

Liu, Bo January 2017 (has links)
At present, the global population is increasing, while soil and fresh water resources for crop production are declining. It is important to adopt sustainable practices to optimise the use of limited natural resources without compromising the environment, and to enhance continuous production in the long term. The rapid growth of UK strawberry industry has been achieved through the precision use of varieties, nutrients and polythene tunnels. This intensive production has caused significant environmental impacts especially Greenhouse Gas (GHG) emissions from the production. Strawberry powdery mildew (Podosphaera aphanis) is a major fungal disease affecting strawberry production worldwide particularly in polythene tunnels. The disease can result in yield losses of up to 70% of the crop. A ruleQbased system was used in the field trials to predict high risk days of P. aphanis development, taking into account the optimal environmental conditions conducive to conidial germination and disease development. The results (Chapter 3) showed that the use of this prediction system achieved satisfactory control of P. aphanis in commercial strawberry production, with reduced fungicide applications compared with commercial spray programme. The results were consistent in two consecutive years and on different varieties. In addition, it was suggested that the use of the prediction system may also lead to lower GHG emissions associated with fewer fungicide applications, thereby benefit strawberry growers both environmentally and economically. Results from 2014 & 2015 silicon fertigation trials showed that the use of a silicon nutrient via the fertigation system reduced the strawberry susceptibility to P. aphanis and twoQspotted spider mites (Tetranychus urticae Koch) in two consecutive years on different varieties (Chapter 4). In both years, crops received the silicon nutrient only without fungicides had both lower rate of epidemic (r) and lower value of Area Under the Disease Progress Curve (AUDPC) (r = 0.0036, AUDPC = 475 in 2014; r = 0.001, AUDPC = 267 in 2015) compared with the untreated control (r = 0.0042, AUDPC = 662 in 2014; r = 0.0011, AUDPC = 281 in 2015). Silicon also delayed the epidemic buildQup in the silicon nutrient only treatment for approximately two weeks compared with the untreated control. Crops from the silicon nutrient plus fungicides treatment had lower susceptibility (r = 0.0012 in 2014; r = 0.0004 in 2015) than those from the fungicides only treatment (r = 0.0017 in 2014; r = 0.0005 in 2015) suggesting that the silicon nutrient may also enhance fungicides performance in reducing the epidemic buildQup when used together. Moreover, the presence of T. urticae on strawberry leaves was significantly lower (P < 0.001) in plants treated with the silicon nutrient than those without. In addition, initial results suggested that silicon may play a positive role in raising °Brix of strawberry leaf petiole, improving pollen viability, and influencing the length of flower receptacle and stamens. Maltmas Farm has a wide range of semiQnatural habitats that provide food and nesting resources for wild pollinators. Hoverflies, bumblebees and solitary bees were found to be the main wild pollinators that pollinate commercial strawberries at Maltmas Farm (Chapter 5). The number of pollinators in tunnels or open fields significantly correlated with the abundance of strawberry flowers (P < 0.05). Pollinator presence also differed between groups throughout the day and over the seasons. Hoverflies appeared early in the day and were abundant in summer months; bumblebees and solitary bees were present most of the day and throughout the season, whereas honeybees were only active in sunny days. Temperatures, relative humidity and cloud coverage also affected pollinator presence. In addition, pollinator activity was not significantly (P > 0.05) affected by the application of the silicon nutrient via the fertigation system. The integrated use of the prediction system (to reduce fungicide applications and subsequent GHG emissions), the silicon nutrient (to reduce crop susceptibility to P. aphanis and T. urticae), and sustainable farmland management (to encourage the presence of wild pollinators) could help strawberry growers to achieve a more sustainable production.
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Contribuição  à avaliação da ecoeficiência na escolha de estruturas de pavimento flexíveis, semirrígidas ou invertidas. / Contribution to the ecoeficiency evaluation on the pavement structure type choice.

Alberto, Vinícius Maróstica 26 October 2018 (has links)
A seleção do tipo de pavimento é baseada atualmente no país considerando-se os custos de implantação e manutenção e o atendimento às normas técnicas, ou seja, a escolha é feita por meio de análise técnico-econômica. Órgãos federais, estaduais e municipais não preveem avaliação quantitativa do consumo de energia e da emissão de poluentes atmosféricos, utilizando somente o fator econômico como parâmetro decisivo sobre duas ou mais alternativas de estruturas de pavimento. Construções e reconstruções de pavimentos consomem um grande volume de energia tanto para obtenção e processamentos dos materiais quanto na aplicação e execução propriamente dita dos serviços. Tendo em vista a necessidade de considerar aspectos de sustentabilidade na escolha entre diferentes tipos de solução de pavimento, buscou-se avaliar a emissão de poluentes e consumo de energia e água para a fase de implantação do pavimento. Para tal foi avaliada a utilização de diferentes programas computacionais capazes de avaliar a questão ambiental qualitativamente, como o GreenroadsTM e o GreenPave, e quantitativamente, o GaBi, DuboCalc, VTTI/UC, ECORCE-M e PaLATE. Este último foi o escolhido para elaboração deste estudo sendo utilizado em análise unitária o que permitiu a elaboração de gráfico de impressão digital ambiental. São apresentados estudos de caso em três metodologias diferentes sendo que a última delas sugere a análise de três matrizes de solução totalizando mais de 230 mil casos que levam a obtenção de três equações de previsão das emissões de CO2 em função do tráfego, condição de suporte do subleito e número estrutural. Ao final, é sugerida a inserção da parcela ambiental na análise para escolha dos pavimentos com a utilização das ferramentas propostas, ou seja, as equações de previsão de emissões de CO2 e o gráfico de impressão digital ambiental. / The pavement structure selection in Brazil nowadays is based considering the costs of construction and maintenance and the check against design standards, in other words, the choice is made by a technical-economic analysis. Brazilian Federal agencies do not provide standards for a quantitative assessment of energy consumption and atmospheric pollutants emission, using only the economic factor as a decision parameter on two or more pavement structures. Pavement construction and reconstruction of pavement structures consume a large volume of energy while obtaining, processing and applying materials during paving services. Considering the need to account aspects of sustainability in the choice between different types of pavement solution, it was sought to evaluate the emission of pollutants and energy and water consumption for the pavement construction phase. In order to do so, it was evaluated the use of different softwares capable of account the environmental question qualitatively, such as the GreenroadsTM and GreenPave, and quantitatively, such as GaBi, DuboCalc, VTTI / UC, ECORCE-M and PaLATE. PaLATE was chosen to be software used in this study being used in unitary analysis that allowed the elaboration of environmental fingerprint graph. Case studies are presented in three different methodologies. The last suggests the analysis of three solution matrices totaling more than 230 thousand cases that leads to obtaining three prediction equations of CO2 emissions as a function of traffic, subgrade support condition and structural number. At the end, it is suggested the insertion of the environmental part in the pavement choose analysis with the use of the proposed tools, the CO2 forecasting emission equations and the environmental fingerprint graph.

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