Дисертації з теми "ENVIRONMENTAL FLOW ASSESSMENT"

Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: ENVIRONMENTAL FLOW ASSESSMENT.

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся з топ-50 дисертацій для дослідження на тему "ENVIRONMENTAL FLOW ASSESSMENT".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.

1

Goz, Caglayan. "Instream Flow Methodologies: Hydrological Environmental Flow Assessment In Pazarsuyu River." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615004/index.pdf.

Повний текст джерела
Анотація:
In Turkey with increasing energy demand by industrialization and urbanization, hydropower seemed to be the most environmental friendly and sustainable solution for the problem. However, hydropower has also environmental effects especially when hydropower projects are numerous on a single river, and they use almost entire water in the river. Environmental flow as a new term became popular in media with increased density of small hydropower projects in Turkey. It is the required flow in the part of diversion for Run-off River type of hydropower plant in order to protect health of the river
in other words, to balance components of the river, including physico-chemical quality standards, surface and groundwater, geomorphological dynamics, social, economic, cultural and landscape values. In this study, an analysis utilizing hydrological (desktop) environmental flow assessment methods is prepared for Turkey, focusing on the Pazarsuyu Basin as a case study, and the results are compared with the applications done by the Governmental Institutions. Moreover, insufficient applications with regard to environmental flow assessment are given and reasons for public concerns are pointed out due to small hydropower development in Turkey.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Lagerblad, Lovisa. "Assessment of environmental flow requirements in Buzi River basin, Mozambique." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150870.

Повний текст джерела
Анотація:
Rivers belong to the world’s most complex ecosystems but increasing demands for water are degrading rivers worldwide. The increase in human populations and activities has resulted in an intense and difficult conflict between the development of rivers as a natural resource and their function as living ecosystems. It is now widely recognized that a naturally variable flow regime is required to sustain freshwater ecosystems. Many countries that experience river degradation have started to implement environmental flows, i.e. the unallocated flow purposely preserved in a river. The objectives of this thesis are twofold. The first aim is to briefly describe the concept and science of environmental flows and the different methodologies for calculating environmental flows. This was done based on a literature review of the subject. The second aim is to present a case study calculating the environmental flow requirements. The case study was conducted through a field study in the Buzi River basin in Mozambique and the subsequent modeling of the environmental flow requirements. The literature study showed that not only the quantity of water is important; the timing and frequency of floods, droughts, low flows and high flows are very important as well. The literature study also showed that the advances in environmental flow science have been remarkable while the water policy and management has not been equally successful in implementing environmental flow standards. The calculation of environmental flow requirements was done with the Desktop Reserve Model developed in South Africa. The results indicated that to maintain the ecological status in the Buzi River at a largely natural condition (ecological category A) an average allocation of 57 % of mean annual runoff (MAR) is required. The present ecological status was determined in Revue River, which is one of the three major tributaries to Buzi River. To maintain the Revue River at its present ecological state requires an environmental flow between 23-37 % of MAR. The major environmental threats in Revue River are erosion and flow modification. The erosion is a consequence from artisanal gold mining, inadequate farming practices and deforestation. The flow alterations are caused by the large Chicamba Dam constructed for the generation of hydropower. One of the questions this thesis aimed to answer was if it was possible to set the present ecological state with a limited amount of data. This study showed that it could be possible but that the confidence level will be low. The relationships between ecological metrics and flow alterations must be investigated in detail for this region before environmental flow requirements can be successfully calculated and implemented.
Floder hör till jordens mest komplexa och känsliga ekosystem, men ett ökat tryck på våra vattenresurser har försämrat situationen för många av världens floder. Befolkningsökningen och den globala utvecklingen har resulterat i en intensiv och komplicerad konflikt mellan utnyttjandet av floder som en naturresurs och bevarandet av deras funktion som unika ekosystem. Det är nu allmänt accepterat att den naturliga flödesvariabiliteten behövs för att bevara våra sötvattenekosystem. Flera länder där försämringen av floder är ett faktum har börjat införa miljöanpassade flöden, det vill säga vatten som medvetet tilldelas flodens ekosystem. Det finns två syften med det här examensarbetet. Det första är att genom en litteraturstudie beskriva miljöanpassade flöden och de modeller som används för att beräkna detta flöde. Det andra målet är att göra en fallstudie och beräkna det miljöanpassade flödet och bestämma den ekologiska statusen för Buzi floden i Moçambique. Litteraturstudien visade att det inte bara är kvantiteten av vatten som är viktigt; tidpunkt och återkomsten av översvämning, torka, lågflöden och högflöden är mycket viktiga om man vill efterlikna det naturliga flödet. Litteraturstudien visade även att framstegen i kunskapen om miljöanpassade flöden har varit stora medan vattenlagstiftningens anpassning och införandet av miljöanpassade flöden har varit svag i flera avseenden. Modellerandet gjordes med den sydafrikanska Desktop Reserve Model. Resultaten från modellen visade att för att bibehålla den ekologiska statusen för Buzi floden i ett nära naturligt stadium (ekologisk klass A) krävs en tilldelning på 57% av medelårsavrinningen. Den nuvarande ekologiska statusen bestämdes i Revue floden, som är en av tre huvudfloder i Buzi avrinningsområdet. För att behålla Revue floden i sitt nuvarande tillstånd skulle kräva ett miljöanpassat flöde på mellan 23-37% av medelårsavrinningen. De största ekologiska hoten i Revue floden visade studien var erosion och flödesförändringar. Erosionen är en konsekvens av guldutgrävning, jordbruk med fel teknik, och skogs­­avverkning. Flödesförändringarna härrör från den stora vattenkraftsstationen Chicamba Dam. En av frågorna den här studien syftade till att besvara var om det är möjligt att bestämma den nuvarande ekologiska statusen med en begränsad tillgång till data. Studien visade att det är möjligt men att osäkerhetsnivån i resultatet kommer att vara stort. Studien visade även att modellen Desktop Reserve Model kan användas för snabba beräkningar av det miljöanpassade flödet, men att mer utförliga studier som till exempel Building Block Methodology måste genomföras innan resultatet med säkerhet kan verifieras. Relationen mellan ekologiska förändringar och flödesvariationer måste utredas i detalj för studieområdet innan de miljö­anpassade flödesbehoven kan bli implementerade med framgång.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Tse, Rosanna. "A critical assessment of two phase flow characterization of soil." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/28178.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

de, Macedo Soares Pires Condeixa Karina. "Material Flow Analysis and environmental impacts assessment of the construction sector in Brazil." Doctoral thesis, Universitat Rovira i Virgili, 2016. http://hdl.handle.net/10803/454715.

Повний текст джерела
Анотація:
L'ampli ús de materials als edificis contribueix a l'escassetat de recursos naturals i a l'abocament de residus al medi ambient. L'Anàlisi del Flux de Materials (MFA) s'ha utiliyat com a eina per aconseguir a desmaterialització i la sostenibilitat dels edificis existents. Aquesta tesi s'organitza en tres capitols principals. El primer capitol presenta una revisi bibliogràfica i un anàlisi bibliometric per recolyar lus sistematic de MFA. El segon capitol proposa un metode basat en el MFA per a modelar la poblacio dels edificis residencials a la ciutat de Rio de Janeiro i el flux de materials de residus, per tal de caracteritzar lstock d'edificis. El tercer capitol introdueix lus combinat de les metodologies d'Anàlisi de Ciclo de Vida i MFA per a modelar els fluxos residuales de la poblacio d'edificis i per a avaluar els seus impactes de cicle de vida. En resum, aquesta tesi explora les variants de la metodologia d'Anàlisi de Flux de Materials i promou un ampli anàlisi dels edificis i dels impactes de cicle de vida dels fluxos de residus.
El amplio uso de materiales en los edificios contribuye a la escasez de recursos naturales y al vertido de residuos en el medio ambiente. El Análisis del Flujo de Materiales (MFA) se ha utilizado como una herramienta para lograr la desmaterialización y la sostenibilidad de los edificios existentes. Esta tesis se organiza en tres capitulos principales. El primer capítulo presenta una revisión bibliográfica y un análisis bibliométrico para apoyar el uso sistemático del MFA. El segundo capítulo propone un método basado en el MFA para modelar la población de los edificios residenciales en la ciudad de Río de Janeiro, y el flujo de materiales y de residuos, con el fin de caracterizar el stock de edificios. El tercer capítulo introcuce el uso combinado de las metodologías de Análisis de ciclo de Vida y MFA para modelar los flujos residuales de la población de edificios y para evaluar sus impactos. En resumen, esta tesis explora las variantes de la metodología de Análisis de Flujo de Materiales y promueve un amplio análisis de los edificios y de los impactos del ciclo de vida de los flujos de residuos.
The extensive use of materials in buildins stocks contributes to the scarcity of natural resources and waste disposal on the environment. Material Flow Analysis (MFA) has been used as a tool to achieve dematerialization and sustainability of buildings stocks. This thesis is organized in three main chapters. The first chapter presents a literature review and a bibliometric analysis for supprting the systematic use of MFA. The second chapter proposes a method based on MFA to model the residential building stock in the city of Rio de Janeiro and their material and waste flows, in order to characterize the stock. The third chapter introduces the combinated use if MFA and Life Cycle Assessment methodologies to model waste flows from a building stock and to assess its life cycle impacts. In summary, this Thesis explores the variants of the MFA and promotes a broadly analysis of a building stocks and life cycle impacts from waste flows.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Poon, David. "Re-conceptualizing the soil and water assessment tool to better predict subsurface water flow through macroporous soils." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119707.

Повний текст джерела
Анотація:
Efforts to manage eutrophication of surface waters should recognize that macropore flow transports significantly more phosphorus (P) to surface waters via tile drains than water that percolates through the soil matrix. For the watershed-scale SWAT (Soil and Water Assessment Tool) model to describe phosphorus transport through tile drains, SWAT needs to partition percolation into macropore flow and matrix flow. The objective of this study was to evaluate the effects of a new macropore flow algorithm on the partitioning of hydrological flows, using input data that are readily available, consistent with the current approach to SWAT modeling. The algorithm was evaluated in a proof of concept outside of SWAT and within a re-conceptualized version, SWAT-QC2. The proof of concept reproduced episodic macropore flows, which increased with greater daily rainfall if infiltration exceeded a threshold that was lower for finer-textured soils. Although the algorithm did not improve predictions of streamflow of an agricultural subwatershed in southern Quebec (30 km2), the algorithm improved SWAT's partitioning between surface runoff and subsurface flow. SWAT-QC2 also predicted reasonably the separation between macropore and matrix components of subsurface flow, upon comparison with results from a chemical-based hydrograph separation of the subwatershed's streamflow. As in the proof of concept, the predicted amount of macropore flow into tile drains was greater under finer-textured soils than coarser-textured soils. By describing the portion of percolation that flows through macropores and potentially controls subsurface P transport, the macropore flow algorithm provides a framework for future developments of SWAT that describe macropore transport of P to tile drains. To improve the partitioning between macropore and matrix flows, future developments of SWAT-QC2 should account for dynamic macropore connectivity and the effects of soil moisture on macropore flow, but more research is needed to determine experimentally the spatiotemporal variation of macropore flow in agricultural soils.
Les stratégies d'intervention ciblées sur la prévention de l'eutrophisation des eaux de surface en milieu agricole devraient prendre en compte que relativement plus de phosphore chemine vers les drains souterrains par les macropores du sol qu'en cheminement matriciel. Afin de décrire les phénomènes de transport de phosphore aux drains, le modèle hydrologique SWAT (Soil and Water Assessment Tool) doit être en mesure de distinguer ces processus de transfert. La présente étude avait pour objectif d'évaluer la performance d'un nouvel algorithme séparant les écoulements matriciels et préférentiels, en mettant à profit des jeux de données existantes et suivant une démarche compatible avec l'approche de modélisation inhérente à SWAT. L'algorithme a d'abord profité d'une validation conceptuelle, hors du modèle SWAT, puis d'une évaluation suivant son intégration à une nouvelle version du modèle hydrologique, SWAT-QC2. La validation conceptuelle de l'algorithme a démontré que les flux matriciels épisodiques prédits augmentent avec les précipitations journalières, à la condition que le taux d'infiltration ait atteint un seuil limite, relativement moins élevé en sol argileux. Bien que l'algorithme n'ait pas amélioré la prédiction du débit total d'un petit bassin versant du Sud du Québec (30 km2), il a néanmoins amélioré la performance du modèle SWAT à répartir les écoulements de surface et souterrains. La comparaison des prédictions du modèle hydrologique avec les résultats de séparation des hydrogrammes à l'exutoire du même bassin versant suivant une méthode chimique témoigne d'une performance réaliste de SWAT-QC2 à prédire la répartition des flux souterrains préférentiels et matriciels. A l'instar de la validation conceptuelle de l'algorithme, les flux préférentiels prédits sont relativement plus importants en sol argileux qu'en texture plus grossière. En décrivant la proportion des écoulements souterrains qui emprunte la voie préférentielle, et qui contrôle potentiellement les transferts souterrains de P, l'algorithme d'écoulement en macropores constitue une assise pour le développement ultérieur de SWAT intégrant une description des transferts souterrains de phosphore vers les drains souterrains. Afin d'améliorer la performance de SWAT-QC2 à séparer les flux préférentiels et matriciels, les développements futurs du modèle hydrologique devraient prendre en compte la nature dynamique de la connectivité des macropores, de même que les effets de l'humidité du sol sur l'écoulement préférentiel. Cette démarche appelle cependant à une meilleure caractérisation expérimentale de la variabilité spatio-temporelle des flux préférentiels en sols agricoles.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Desai, Ahmed Yacoob. "Development of a hydraulic sub-model as part of a desktop environmental flow assessment method." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1006200.

Повний текст джерела
Анотація:
Countries around the world have been developing ecological policies to protect their water resources and minimise the impacts of development on their river systems. The concept of ‘minimum flows’ was initially established as a solution but it did not provide sufficient protection as all elements of a flow regime were found to be important for the protection of the river ecosystem. “Environmental flows” were developed to determine these flow regimes to maintain a river in some defined ecological condition. Rapid, initial estimates of the quantity component of environmental flows may be determined using the Desktop Reserve Model in South Africa. However, the Desktop Reserve Model is dependent upon the characteristics of the reference natural hydrology used. The advancements in hydraulic and ecological relationships from the past decade have prompted the development of a Revised Desktop Reserve Model (RDRM) that would incorporate these relationships. The research in this thesis presents the development of the hydraulic sub-model for the RDRM. The hydraulic sub-model was designed to produce a realistic representation of the hydraulic conditions using hydraulic parameters/characteristics from readily available information for any part of South Africa. Hydraulic data from past EWR studies were used to estimate the hydraulic parameters. These estimated hydraulic parameters were used to develop hydraulic estimation relationships and these relationships were developed based on a combination of regression and rule-based procedures. The estimation relationships were incorporated into the hydraulic sub-model of the integrated RDRM and assessments of the hydraulic outputs and EWR results were undertaken to assess the ‘applicability’ of the hydraulic sub-model. The hydraulic sub-model was assessed to be at a stage where it can satisfactorily be incorporated in the RDRM and that it is adequately robust in many situations. Recommendations for future work include the refinement of estimation of the channel forming discharge or the use of spatial imagery to check the maximum channel width estimation. It is also proposed that a future version of the hydraulic sub-model could include flow regime change impacts on channel geomorphology and sedimentology so that flow management scenarios can be more effectively assessed.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Lundkvist, Markus. "Accident Risk and Environmental Assessment : Development of an Assessment Guideline with Examination in Northern Scandinavia." Doctoral thesis, Uppsala : Department of Social and Economic Geography, Uppsala University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5849.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Franzén, Linda. "Water flow analysis of Jästbolaget : An assessment of the yeast production’s environmental impact, caused by its water consumption." Thesis, KTH, Industriell ekologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147861.

Повний текст джерела
Анотація:
This bachelor thesis is carried out for the department of Industrial Ecology at the Royal Institute of Technology in Stockholm. Water in Sweden is a resource in abundance. Even so, it is an expensive one and may even become more expensive due to climate changes. Hence, there are for companies’ both economic and environmental benefits to induce minimization of the water flow. The aim of this report is to assess the sustainability of the water usage within the production of liquid, active dry and compressed fresh yeast which also goes under the common name of baking yeast. The assessment has been done through a water flow analysis in addition with a water footprint. The system borders for the water flow analysis comprises the outtake of water from Mälaren, the production at Jästbolaget and the final treatment at Käppala wastewater treatment plant. The water considered in the production is mainly the municipal-water flow within the production and to a less extent the water used for cooling. Substances contained in the water flow which are paid particular attention are the amount of total organic carbon, phosphorus and nitrogen. The method for gathering information and data has been through interviews and mail correspondence with employees at Jästbolaget and Käppala. Furthermore, a literature study has been conducted. The conclusion of this report is that the water flow has a low impact and that Jästbolaget has taken appropriate measures to minimize their impact and usage of water. However, improvements can always be made but it is rather a matter of the methods efficiency to further decrease the usage of water and emission of phosphorus and nitrogen.
Detta kandidatexamensarbete är utfört på institutionen för Industriell Ekologi på Kungliga Tekniska högskolan i Stockholm. Trots att Sveriges vattenresurser idag finns i överflöd är vatten en dyr resurs. I framtiden finns också risken att priset kommer att öka på grund av klimatförändringar. Detta beror på att kvalitén på våra vattentillgångar kan komma att minska vilket då leder till att vattnet behöver renas ytterligare. Det finns alltså redan idag men även kommande anledningar för företag att minska sin vattenkonsumtion. Utöver de ekonomiska fördelarna finns det även ett flertal med avseende på miljöpåverkan. Målet med denna rapport är att bedöma vattenflödets miljöpåverkan i produktionen av flytande, torr- och pressjäst, även kallade bakjäst. Bedömningen har utförts med hjälp av en vattenflödesanalys samt ett vattenfotavtryck. Systemgränserna innefattar uttaget av vatten från Mälaren, produktionen vid Jästbolaget och den slutgiltiga behandlingen vid Käppala reningsverk. De uppmärksammade ämnena i vattenflödet är totalt organiskt kol, fosfor och kväve. Information och data har blivit insamlat genom intervjuer och mejlkorrenspondens samt genom en litteraturstudie. Slutsatsen av detta projekt är att Jästbolagets vattenflöde har en låg miljöpåverkan och att Jästbolaget att vidtagit lämpliga åtgärder för att minska deras påverkan. Förbättringar kan dock alltid göras men i detta fall handlar det framförallt om att effektivisera de metoder de redan använder för att i största möjliga mån minska vattenanvändningen och utsläppen av fosfor och kväve.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Whitley, Annie R. "Method Development for Detecting and Characterizing Manufactured Silver Nanoparticles in Soil Pore Water Using Asymmetrical Flow Field-Flow Fractionation." UKnowledge, 2012. http://uknowledge.uky.edu/pss_etds/9.

Повний текст джерела
Анотація:
Recent advances in nanotechnology have led to the production of materials with nanoscale dimensions (nm) and properties distinctly different from their bulk (>100 nm) counterparts. With increased use, it is inevitable that nanomaterials will accumulate in the environment and there is concern that the novel properties of nanomaterials could result in detrimental environmental and human health effects. In particular, there has been concern recently regarding the use of silver (Ag) based nanomaterials as antimicrobial agents in consumer and medical products. Current regulations dealing with the discharge of metals into the environment are based on total concentrations with no consideration for the form (e.g., ionic, nanoparticle, colloid) which can largely determine toxicity. Methods for the identification and characterization of nanoparticulates within complex matrices are lacking and the development of robust methods for this purpose are considered a high priority research area. This research focuses on the development and application of a novel method for characterizing Ag manufactured nanoparticles (MNPs) within terrestrial environments, in particular in soil pore water, with applications relevant to other metal MNPs as well. The method was then applied to understand the dynamics and behavior of Ag MNPs in soil and soil amended with sewage sludge biosolids.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Assefa, Getachew. "On sustainability assessment of technical systems : experience from systems analysis with the ORWARE and EcoEffect tools /." Doctoral thesis, Stockholm : Division of Industrial Ecology, Deparment of Chemical Engineering, School of Chemical Science and Engineering, Royal Institute of Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-550.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
11

Kabiri, Reza. "Assessment of climate change impact on runoff and peak flow : a case study on Klang watershed in West Malaysia." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14149/.

Повний текст джерела
Анотація:
Climate change is a consequence of changing in climate on environment over the worldwide. The increase in developmental activities and Greenhouse Gases (GHGS) put a strain on environment, resulting in increased use of fuel resources. The consequence of such an emission to the atmosphere exacerbates climate pattern. There are numerous Climate Change Downscaling studies in coarse resolution, which have largely centred on employing the dynamic approaches, and in most of these investigations, the Regional Climate Model (RCM) has been reported to numerically predict the local climatic variables. The majority of previous investigations have failed to account for the spatial watershed scale, which could generate an average value of downscaled variables over the watershed scale. To address shortcomings of previous investigations, the work undertaken in this project has two main objectives. The study first aims to implement a spatially distributed Statistical Downscaling Model (SDSM) to downscale the predictands, and second to evaluate the impact of climate changes on the future discharge and peak flow. It is conducted based on the IPCC Scenarios A2 (Medium–High Emission scenario) and B2 (Medium–Low Emission scenario). The main objectives of the study are as follows: • To generate fine resolution climate change scenarios using Statistical Downscaling Model in the watershed scale, • To project the variability in temperature, precipitation and evaporation for the three time slices, 2020s (2010 to 2039), 2050s (2040 to 2069) and 2080s (2070 to 2099), based on A2 and B2 scenarios, • To calibrate and validate hydrological model using historical observed flow data to verify the performance of the hydrological model, • To evaluate the impact of climate changes on the future discharge and future peak flow for three timeslices: 2020s (2010 to 2039), 2050s (2040 to 2069) and 2080s (2070 to 2099). Thus, to meet the objectives of the study, projection of the future climate based on climate change scenarios from IPCC is carried out as the most important component in the research. The results of this research are presented as follows: • The study indicates that there will be an increase of mean monthly precipitation but with an intensified decrease in the number of consecutive wet-days and can be concluded as a possibility of more precipitation amount in fewer days. • The watershed is found to experience increased rainfall towards the end of the century. However, the analysis indicates that there will likely be a negative trend of mean precipitation in 2020s and with no difference in 2050s. The precipitation experiences a mean annual decrease by 7.9%, 0.6% in 2020s and 2050s and an increase by 12.4% in 2080s corresponding A2 scenario. • The maximum and minimum temperatures are likely to be increased toward the end of the century by 2.7oC and 0.8oC respectively when compared to the current observed temperature (1975-2001) at the Subang temperature station. • The average annual mean discharge is predicted to be decreasing by 9.4%, 4.9% and an increase of 3.4% for the A2 and a decrease of 17.3%, 13.6% and 5.1% for the B2 scenario, respectively in the 2020s, 2050s and 2080s. • The average annual maximum discharge is projected to decrease by 7.7% in 2020s and an increase by 4.2% and 29% in A2 scenario for 2050s and 2080s, respectively. But there will most likely be a decrease in the maximum discharge for all the future under B2 scenario. It is projected a decrease of 32.3%, 19.5% and 2.3% for 2020s, 2050s and 2080s, respectively. • The projected mean discharge indicates a decline in the months from January to April and also from July to August in all the three future periods for A2 and B2 scenarios. There is an increasing trend in the discharge of September and October in the 2020s according to the A2 and B2 scenarios. • The highest increase in precipitation frequency occurs in 2080s under A2 scenario in which the increase in the magnitude of 100 Return Year is found to be 88% greater than the one of the maximum observed. • The highest increase in flood frequency at Sulaiman streamflow station occurs in 2080s under A2 scenario. The increase in the magnitude of 100 Return Year is found to be 26.5% greater than the one of the maximum observed.
Стилі APA, Harvard, Vancouver, ISO та ін.
12

Patterson, Joanne Louise. "Urban scale modelling of traffic and cycling flow using spatial analysis and an assessment of factors that influence cyclist behaviour." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/66970/.

Повний текст джерела
Анотація:
To understand and facilitate modal shift to more sustainable modes of transport there is a need to model accessibility and connectivity at an urban scale using data collection and modelling procedures that require less data and specialist input than traditional transport models. This research has used spatial analysis modelling procedures based on space syntax to investigate the potential to model aggregate traffic flows at an urban scale, and to investigate the potential to apply the same methodology to model both aggregate and individual cycle flows. Cyclist behaviour has been investigated through a questionnaire to support modelling work. The research has demonstrated that spatial analysis modelling is an effective means of representing urban scale motor traffic network, however, modifications to the model were required to achieve a correlation between modelled and measured motor traffic flow comparable to other modelling procedures. Boundary weighting was found to be effective at representing traffic crossing the boundary of an isolated urban sub-area, but was not so effective at an urban scale. Road weighting was found to be effective in improving model performance by representing traffic flows along routes according to a national classification scheme. It was demonstrated that these modelling principles could be used to represent an urban bicycle network and that the impact of the modification of infrastructure on relative flows of both cyclists and motor traffic could be accommodated. The modelling approach has the potential to be extremely useful at an early planning stage to represent changes to flows across the network. A survey of behaviour identified that cyclists modify their journey to use cycling facilities such as on-road lanes and off-road paths, or to avoid particular areas perceived to be less favourable for cyclists and that analysis indicates that it is difficult to predict (25% from survey) individual route choice. Results indicate that there were more opportunities related to route characteristics that could be influenced by infrastructure changes for occasional cyclists than for frequent/everyday cyclists.
Стилі APA, Harvard, Vancouver, ISO та ін.
13

Garrido, Baserba Manel. "Development of an environmental decision support system for the selection and integrated assessment of process flow diagrams in wastewater treatment." Doctoral thesis, Universitat de Girona, 2013. http://hdl.handle.net/10803/108953.

Повний текст джерела
Анотація:
The wastewater treatment plays an important role in the maintenance of natural water resources. However, regardless of the technology used or the level of treatment required, the treatment plants of the XXI century are highly complex systems that not only need to meet technical requirements, but also environmental and economic criteria. In this context, decision support systems for environmental domains (English, Environmental Decision Support Systems or EDSS) are configured as an effective tool to support the selection and evaluation of integrated water treatment alternatives. The EDSS designed can be defined as interactive software, flexible and adaptable, which links the numerical models / algorithms, techniques and environmental ontologies, knowledge-based environment, and is capable of supporting decision making, either in choosing between different alternatives, improving potential solutions, or in the integrated assessment using methodologies ranging from environmental (Life Cycle Analysis) to economic
La depuració d’aigües residuals juga un paper fonamental en el manteniment dels recursos hídrics naturals. Tanmateix, sigui quina sigui la tecnologia emprada o el nivell de depuració requerit, les plantes de tractament del segle XXI són sistemes d’alta complexitat, que no només han de satisfer requeriments de tipus tècnic, sinó també de tipus ambiental i econòmic. En aquest context, els sistemes de suport a la decisió en dominis ambientals (en anglès, Environmental Decision Support Systems o EDSS) es configuren com una eina eficaç per donar suport a la selecció i a l’avaluació integrada de diferents alternatives de depuració d’aigües. El EDSS dissenyat pot definir-se com un programari interactiu, flexible i adaptable, que vincula els models numèrics/algoritmes amb tècniques basades en el coneixement i ontologies ambientals, i que és capaç de donar suport a la presa de decisió, ja sigui en l’elecció entre diferents alternatives, millorant una solució, o bé en l’avaluació integrada a través de metodologies ambientals (Anàlisi de Cicle de Vida) i econòmiques
Стилі APA, Harvard, Vancouver, ISO та ін.
14

Arvanitis, Konstantinos. "MACROALGAE IN THE BIOREFINERY : A SUBSTANCE FLOW ANALYSIS AND ENVIRONMENTAL ASSESSMENT OF AN EXTRACTION PROCESS OF THE MAJOR COMPONENTS IN SACCHARINA LATISSIMA." Thesis, KTH, Industriell ekologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183278.

Повний текст джерела
Анотація:
A turn to more sustainable resources has lead the research during the last decades to algae. Algae is a resource that has been utilized for thousands of years offering a variety of possibilities. Nevertheless modern technology were able to uncover algae’s great potential and pave the way for alternative uses such as biofuel and biomaterial production. Towards that direction, ‘Seafarm’ aims in utilizing algae in the most efficient and sustainable way. For that purpose various steps have been established, including the biorefinery step which entail among other the extraction of carbohydrates from brown algae. The current thesis is based on an extraction of carbohydrates from Saccharina latissima, a brown algae species, which was developed by Viktor Öberg during his master thesis at KTH. The aim of this work is to assist in the scaling up of that laboratory process by analyzing the basic steps and substances of the process, investigating its environmental performance and identifying improvement areas for theoretical optimization. The results of the aforementioned analysis include a substance flow analysis which reveals the basic steps of the process and constitute the basis for further analysis. The second step examines the environmental performance of the process based on the chemical selection. Hence the results are a risk assessment of chemicals with performance indicators for each chemical as well as the whole process. The final part provides a theoretical optimization of the process based on literature studies where the recommendations are divided in production optimization and environmental performance. The above results constitute the basis of the analysis of the process and sets the foundations for scaling up the process at an industrial level. The current analysis in combination with an energy and economic assessment could be used for the designing of the process and its integration in the biorefinery.
Стилі APA, Harvard, Vancouver, ISO та ін.
15

El-Geziry, Tarek Mohamed Ahmed. "Environmental impact assessment and process simulation of the tidal current energy resource in the Strait of Messina." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4779.

Повний текст джерела
Анотація:
Interest in exploring renewable energy resources has increased globally, especially with recent worldwide intentions to maintain the global climate. Looking at the oceans as a vast sustainable clean energy resource to satisfy present high humankind energy demands has been strongly recommended. Several types of renewable energy resources exist in the oceans: waves, tides, thermal and salinity variations, currents, and offshore winds. Exploiting tidal currents is considered one of the most effective approaches to the generation of electricity. Tidal turbines are deployed beneath the sea surface to transfer the kinetic energy in tidal currents to mechanical energy suitable for ongoing conversion to electricity and subsequent transmission. However, choosing a suitable site to deploy these turbines is not a trivial process. Various constraints must be satisfied subject to basic criteria dependent upon local factors, technology limitation and economic consideration. In addition, an important issue to consider is taking care to harness energy from tidal currents with minimum possible impact on the surrounding environment. The present study justifies the nomination of the Strait of Messina as an exceptional tidal current energy resource within the Mediterranean Sea basin. The maximum tidal current velocity at spring peak tide through the Strait may exceed 3 m/s. This mainly results from the tidal phase-difference (180°) between the northern (Tyrrhenian Sea) and southern (Ionian Sea) tips of the Strait, associated with a difference of 0.27 m in tidal wave amplitudes. In addition, the complex coastline configuration of the Strait plays an important role in enhancing tidal current velocities. Therefore, the Strait of Messina fulfils the basic criterion (2 m/s tidal current velocity) to be considered as a valid tidal current energy resource. This massive tidal current energy resource is assessed in the present study. A detailed full desk-based Environmental Impact Assessment (EIA) study is performed using the interactive matrix approach in order to investigate the anticipated environmental impacts on the marine ecosystem of the Strait of Messina resulting from the harnessing of energy from its tidal currents. Through the EIA study the different environmental components, both biotic and abiotic, which may be affected by the energy extraction process, are explained. In addition, the proposed key project activities are listed; the likelihood of occurrence and the magnitude of impact interaction with the environmental components are evaluated. The final judgment matrix guides to make a right decision on the proposed project. From the resulted matrix, the major impacts do not exceed 10% of the total anticipated effects. The positive point is that all the expected impacts, including the majors, can be controlled and minimised to the lowest possible limits by applying a good monitoring programme. The University of Edinburgh “Tidal Flow Development (TFD)” numerical model is used to mimic the tidal environment of the Strait of Messina in different cases. The model successfully simulates the tidal flow regime within the Strait under some exceptional conditions. Modifications to the main numerical code and coefficients were necessary in the present research to adjust the model according to each case study. In the three different cases of simulation, using these exceptional coefficients, the model simulates the main tidal characteristics of the tidal flow within the Strait. According to the results of the numerical simulation process, tidal currents are more intensive close to the eastern coast of the Strait of Messina near to Punta Pezzo. This area is far from any ferry route between Italy and Sicily. The best location to deploy tidal turbines for the energy extraction process is therefore recommended to be within these surroundings. Finally, a physical (laboratory) model is used to simulate the flow regime within the Strait of Messina. The Particle Image Velocimetry (PIV) technique was applied in the flow-table tank at the University of Edinburgh. The physical model simulates the flow behaviour within the Strait of Messina to a satisfactory degree. The cyclonic and anti-cyclonic motions observed at the southern extremity of the Strait are also very well simulated. The results of the present study assure confidence in the use of tidal currents within the Strait of Messina as a renewable energy resource. The safety of the environment must be ensured by following environmental guidelines, respecting the energy extraction limits and by applying an effective monitoring programme. The later is strongly recommended to be an adaptive one in which higher environmental authorities are able to watch, revise and control the environmental team within the project. These authorities are also able to postpone the project in case of any severe environmental case. The simulation processes emphasize the effect of morphometry and topography in enhancing tidal currents in the Strait of Messina. Moreover, numerical simulation assures that the complex morphometry and bathymetry, in addition to the open boundaries of the Strait of Messina, are challenging issues for modellers in order to mimic the real tidal current resource in the case of the Strait of Messina. The study also strongly recommends applying a more effective numerical model than TFD to assess the tidal hydrodynamical environment before and after any proposed energy extraction process. This will certainly, with the EIA of the marine ecosystem, help to make a right decision about the proposed project in order to achieve the goal of using clean and clear renewable energy resources while maintaining both natural and hydrodynamical environments to the most possible safest degree.
Стилі APA, Harvard, Vancouver, ISO та ін.
16

Longnell, Frida. "Environmental Performance from Circularity in Products : A Case Study on LED Lighting Fixtures." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-73604.

Повний текст джерела
Анотація:
The circular economy is promoted by the EU, governments, and businesses all over the world as a concept to reach a sustainable future. The concept is embedded into the UN Sustainable Development Goals for 2030 and aims to decouple economic growth and environmental pressure. Many studies have been conducted on the circular economy in recent years but the research on the actual environmental performance of the concept is limited. To move forward with the concept of the circular economy and reach a sustainable future, the environmental performance must be investigated. In this thesis, the environmental impact of circularity in products is investigated by comparing the environmental impact from one circular and one linear product case. To achieve this, the environmental impact and the degree of circularity is calculated with two different methods. The circularity is calculated with a circularity indicator called the Linear Flow Ratio and the environmental impact is assessed with the environmental evaluation technique Life Cycle Assessment (LCA). In the LCAs, the cases are compared for different environmental impact categories (e.g. global warming). The product that is investigated is an LED lighting fixture from the company 2P1. The circular case is based on a leasing business model and includes remanufacturing, reuse and recycling. The linear case includes production, sales, use, and disposal. The LCA results show that the environmental impact from the circular case is lower for all environmental impact categories. The environmental impact is almost exclusively from the manufacturing phase (including extraction and production of raw materials) and the use phase. The circularity results from the Linear Flow Ratio show contradicting results, presenting that the degree of circularity is higher for the linear case. By comparing the results to calculations from another circularity indicator (Material Circularity Indicator), it is concluded that a unified framework for circularity measurements is required.
Cirkulär ekonomi är introducerat av EU, länder och företag över hela världen som ett koncept för att nå en hållbar framtid. Den cirkulära ekonomin är en del av arbetet mot agenda 2030 för hållbar utveckling och strävar efter att frånkoppla ekonomisk tillväxt från miljöpåverkan. Det har forskats mycket på cirkulär ekonomi under de senaste åren men studier som undersöker det miljömässiga utförandet av konceptet saknas. För att fortsätta att utveckla konceptet och för att nå en hållbar framtid så måste den miljömässiga påverkan från cirkularitet undersökas. I denna studie undersöks miljöpåverkan från cirkularitet hos produkter genom att jämföra miljöpåverkan från ett cirkulärt och ett linjärt fall. Miljöpåverkan och cirkularitetsgraden beräknas med två olika metoder. Cirkulariteten beräknas med cirkularitetsindikatorn Linear Flow Ratio och miljöpåverkan analyseras men livscykelanalys. I livscykelanalyserna värderas miljöpåverkan för de två fallen för olika påverkanskategorier (t.ex. global uppvärmning). Produkten som undersökt är en LED-armatur från företaget 2P1. Det cirkulära fallet basers på uthyrning av armaturerna och innehåller renovering, återanvändning och återvinning. Det linjära fallet innehåller produktion, försäljning, användning och bortskaffande av produkten. Resultaten från livscykelanalyserna visar att det cirkulära fallet medför mindre miljöpåverkan för alla kategorier. Miljöpåverkan kommer nästan enbart från produktion (inklusive material) samt användning. Cirkularitetsresultaten från Linear Flow Ratio visar motsägelsefulla resultat då det linjära fallet har en högre cirkularitetsgrad än det cirkulära fallet. Genom att jämföra resultaten med beräkningar från en annan cirkularitetsindikator (Material Circularity Indicator) kan det fastställas att ett enhetligt ramverk för beräkning av cirkularitet är nödvändigt framöver.
Стилі APA, Harvard, Vancouver, ISO та ін.
17

Tarbet, Karl L. "Evaluation of Two-Dimensional Hydraulic Modeling in a Natural River and Implications in Instream Flow Assessment Methods." DigitalCommons@USU, 1997. https://digitalcommons.usu.edu/etd/4423.

Повний текст джерела
Анотація:
The Logan River was used as a study site to assess the capabilities of two-dimensional depth-averaged hydraulic modeling in the x-y plane of a natural river for use with instream flow studies. Data were collected to spatially represent the study reach with depth, velocity, northing, easting, elevation, and substrate values using a total station and electronic velocity meter. Computational finite element meshes were generated using four different density levels of geometry data to examine the relationship between field data density and computational mesh on geometry errors. Geometry errors were found to be related to smoothing effects, which removed complex channel geometries while overall mesh geometry errors were related to data density in homogeneous versus heterogeneous channel conditions. Results indicate that required field data can be optimized with lower data densities in homogenous sections of the river channel. Of the two hydraulic models examined, the U.S. Army Corps of Engineers RMA2 model could not be adequately calibrated given the high slope within the study reach and therefore all subsequent evaluations were made utilizing the CDG2D model. CDG2D model performance was best in the lower gradient sections of the test section at both calibrated and simulated flows with increasing errors for water surface and associated depth and velocity errors as channel gradient increased. These results suggest that additional research is needed to define limiting gradients under which application of this class of hydrodynamic model can be expected for practical instream flow assessments.
Стилі APA, Harvard, Vancouver, ISO та ін.
18

Sam, Frederick. "The assessment of potential impacts of open cast gold mining on the regional groundwater flow system in hard rock environments : with special reference to Ghana." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4486/.

Повний текст джерела
Анотація:
We consider a simple semi-empirical scoping calculation in conjunction with mathematical models to estimate the radius of impact (Ri) and to determine the circumstances under which gold mines in Ghana are likely to have adverse effect on water levels and volumes in surrounding villages/farms. The approach involves the assessment of local mine geometries, collation and examination of hydraulic conductivity data and the assessment of recharge infiltration rate. Most of the models used with the entire conductivity dataset (Group A) predicted very close radius of impacts to mine with less than few 100m with a median distance of 400m from the mine’s edge. Although it is expected that 25% of cases could reach up to 2km and further if the system was anisotropic. Derogation of water level and volume is more of a problem for Group B and C aquifer systems of higher conductivity values. Model results show that 50% of cases could reach up to 3.6km with a range of 2.7km to 5.1km, and 3km with a range of 2km to 4.6km from mine centre respectively. Nevertheless, Ri could reach 7.6km and further in extreme cases if the system was anisotropic. With regards to Ghana, by constraining conductivity values using water volumes produced by mines in Ghana, and comparing with the model output, it is tentatively suggested that the most likely Ri values are those calculated with the Group B dataset. It should, however, be noted that this results are very sensitive to hydraulic conductivity, and therefore there is the need in Ghana to publish conductivity and volume data to enable suggestions from this work to be confirmed.
Стилі APA, Harvard, Vancouver, ISO та ін.
19

Torabi, Haghighi A. (Ali). "Analysis of lake and river flow regime alteration to assess impacts of hydraulic structures." Doctoral thesis, Oulun yliopisto, 2014. http://urn.fi/urn:isbn:9789526206684.

Повний текст джерела
Анотація:
Abstract A key challenge in Integrated Water Resources Management (IWRM) is determination of environmental flow (EF). This is relevant in all water use scenarios and river regulation work. Water use and management alter water availability for ecosystems and the timing and distribution of runoff. Increased water consumption and allocation of water to different types of consumption impose pressures on aquatic ecosystems, affecting their status and ability to deliver important services, well–known examples being the Aral Sea in Asia and Lake Chad in Africa. This thesis presents new methods to determine the impacts of hydraulic structures on the flow regime of lakes and rivers. Methods to quantify different characteristics of flow in a non–dimensionless way are also presented. These tools allow more environment–based regulation of flow regimes. By using three main flow characteristics of river regime (magnitude, timing and intra–annual), three impact factors, MIF (magnitude impact factor), TIF (timing impact factor) and VIF (variation impact factor), were developed. Combining these impact factors produced a new river impact (RI) index to assess the impacts of hydraulic structure using monthly flow data. Based on RI variations, a classification was developed rating impacts along a scale from ‘Low’ to ‘Drastic’. The importance of climate patterns and river flow regime in controlling lake levels was examined. The lake simulation results were compared using a new index, Degree of Lake Wetness (DLW) and lake response time to changes in hydrology or climate was evaluated. Environmental flow allocation and optimisation of annual EF distribution are critical for ecosystem health. Flow release from reservoirs can be partly supplemented or compensated for by natural runoff from downstream (residual) catchment areas. In a new hydrological approach, optimal intra–annual flow regime for EF can be estimated while considering water inflow from the downstream residual sub-catchment. This thesis provides methods and indices to help quantify river and lake regimes, better understand the possible impacts of changes and manage these impacts optimally. This knowledge is crucial for decision making about EF regimes and achieving water release patterns from dams and hydropower that minimise the hydrological, morphological and biological impacts
Tiivistelmä Integroidun vesivarojen suunnittelun ja hallinnan (IWRM) yhtenä haasteena on ympäristövirtaaman määrittäminen valuma–alue-tasolla. Tämä on tärkeää arvioitaessa säännöstelyn ja vesirakentamisen ympäristövaikutuksia. Vedenkäyttö ja hallinta muuttavat veden saatavuutta jokiekosysteemissä ja virtaaman vuosittaista ajoittumista sekä jakautumista eri kuukausien välillä. Vesivarojen lisääntyvä käyttö eri tarkoituksiin voi vaikuttaa vesiekosysteemeihin ja niiden tuottamiin ekosysteemipalveluihin. Aral–järvi Aasiassa ja Chad–järvi Afrikassa ovat hyviä esimerkkejä veden liiallisesta käytöstä ja ympäristönäkökulman huomiotta jättämisestä. Väitöstyön keskeisin tavoite oli kehittää menetelmiä, joilla voidaan arvioida miten vesirakentaminen vaikuttaa jokien virtaamiin ja järvien vedenpintoihin. Jotta vesistövaikutuksia voidaan yleistää, menetelmät kehitettiin dimensiottomiksi. Nämä menetelmät luovat perustan ympäristöystävällisemmällä vesistöjen virtaamien säännöstelylle. Käyttäen kuukausittaista keskivirtaamaa ja kolmea tyypillisintä virtaamaluokkaa (suuruus, ajoittuminen ja vuodenaikainen vaihtelu), määritettiin uusi yhdistetty jokivaikutusindeksi (RI). Tämän indeksin avulla voitiin lopulta arvioida vesirakentamisen vaikutusta. Perustuen RI-indeksiin, usean joen vesirakentamisen vaikutuksia arvioitiin luokittelemalla vaikutukset vähäisiksi tai merkittäviksi. Työssä tarkasteltiin ilmaston vaihtelun ja jokien virtaamaolosuhteiden vaikutusta järvien vedenpintoihin. Järvisimuloinnin tuloksia verrattiin puolestaan käyttäen indeksiä, joka kuvaa järvessä tapahtuvia muutoksia suhteessa hydrologisiin ja ilmastollisiin olosuhteisiin. Väitöskirja käsittelee myös ympäristövirtaamien (EF) keskeisiä kysymyksiä: vedenkäytön jakautumista ja vuosittaisen virtaaman optimointia ympäristövirtaaman näkökulmasta. Työssä käytetään uutta hydrologista lähestymistapaa arvioimaan ympäristövirtaaman optimoitua kausivirtaamavaihtelua. Tässä lähestymistavassa vesivarastoaltaista lähtevää virtaamaa voidaan osittain täydentää tai kompensoida alapuoliselta valuma–alueelta tulevalla virtaamalla. Väitöstyön tulokset lisäävät ymmärrystä vesivarojen kestävästä käytöstä. Lisäksi työssä kehitetyillä menetelmillä voidaan määrittää ja optimoida jokien ja järvien virtaamaolosuhteita erilaisissa tilanteissa. Väitöstyö tarjoaa uusia käytäntöjä päätöksentekoon liittyen ympäristövirtaamaolosuhteisiin ja -jakaumiin vesivoima- ja vedenkäyttökysymyksissä ottaen huomioon hydrologiset, morfologiset ja biologiset rajoitteet
Стилі APA, Harvard, Vancouver, ISO та ін.
20

Marx, Conrad. "Prediction of antibiotic mass flows in urban catchments and their environmental prioritization." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-211581.

Повний текст джерела
Анотація:
Urban emissions of antibiotics into the environment have the potential to adversely affect terrestrial and aquatic organisms. Developed standardized test methods allow the quantification of the resulting ecotoxicological risk, which strongly relies on a comprehensive situation analysis by predicting or measuring a representative antibiotic concentration of interest. Predicting the input loads of antibiotics to wastewater treatment plants using secondary input data (e.g. prescriptions) is a reasonable method if no analytical data is available. The absence of such data poses the question of an aquired reasonable sample quantity to capture local seasonal differences in prescriptions as well as flow conditions within the catchment area. Both, the theoretical and measurement based determination of environmental concentrations have been scarcely verified in practice. Hence, high resolution prescription data in combination with an extensive monitoring campaign at the wastewater treatment plant Dresden-Kaditz (WWTP) were used as a basis to evaluate the reliability of predicting and measuring urban antibiotic emissions. As expected, the recovery of antibiotic input loads strongly varies among substances. The group of macrolides as well as sulfamethoxazole and trimethoprim were almost fully recovered whereas nearly all substances of the beta-lactam family exhibit high elimination rates during the wastewater transport in the sewer system. Yet other antibiotics (e.g. fluoroquinolones) show distinct fluctuations through the year, which was not obvious from relatively constant prescriptions. The latter substances are an example that available data are not per se sufficient to predict the actual release into the environment which, in certain cases, emphasizes the necessity of adequate measuring campaings. The extensive data pool of this study was hence used to calculate the necessary number of samples to determine a representative annual mean load to the WWTP. Based on the applied approach, a minimum number of 20 to 40 samples per year is proposed to reasonably estimate a representative annual input load of antibiotics and other micropollutants. Regarding the WWTP, the mass flow analysis revealed that macrolides, clindamycin/ clindamycin-sulfoxide and trimethoprim were mainly released with the effluent, while penicillins, cephalosporins as well as sulfamethoxazole were partly degraded in the studied WWTP. Levofloxacin and ciprofloxacin are the only antibiotics under investigation with a significant mass fraction bound to primary, excess and digested sludge. In this context, the sludge concentrations are considered to be highly inconsistent which leads to questionable results. It remains unclear whether the inconsistencies are due to insufficiencies in sampling and/or analytical determination or if the fluctuations can be considered reasonable for digesters. Subsequently, verified antibiotic loads were evaluated regarding their ecotoxicological effects in the aquatic environment. Two approaches were applied (1) to address the ecological impact on individual trophic levels algae, daphnia and fish, and (2) to assess the possible synergistic potential of antibiotic combinations. Ciprofloxacin, levofloxacin and the group of cephalosporins showed to significantly affect the aquatic environment. They either have the highest impact on (one of) the lowest trophic level(s) or disproportionately increase the ecotoxicological risk due to their synergistic characteristics. In this regard, the deficiencies regarding the input prediction of these antibiotics is of particular concern. The underestimation of such critical mass flow conditions weakens the approach of assessing environmental risks on the basis of secondary data like prescriptions. Hence, efforts must be made to further develop the projection model by improving the quality of secondary data, identifying additional emitters and understanding possible retention and degradation dynamics of antibiotics within the sewer system
In der Humanmedizin eingesetzte Antibiotika werden im menschlichen Körper nicht vollständig metabolisiert und gelangen über die Ausscheidungen in das kommunale Abwasser. In der Kläranlage erfolgt nur eine unvollständige Elimination dieser Stoffe, so dass der Kläranlagenablauf einen Hot Spot für Antibiotikaemissionen in die Umwelt darstellt. Das induzierte ökotoxikologische Risiko kann anhand standardisierter Testverfahren und allgemein anerkannter Bewertungsansätze für Einzelsubstanzen abgeschätzt werden. Erfolgt jedoch die Betrachtung von Antibiotikagemischen, wie es für den gereinigten Ablauf einer Kläranlage sinnvoll ist, sind aufgrund zumeist unspezifischer Wirkmechanismen und dem Mangel an repräsentativen Daten eine Reihe von Vereinfachungen und Annahmen zu treffen. Es besteht in der Folge die Gefahr einer Unterschätzung des durch Substanzgemische hervorgerufenen ökotoxikologischen Risikos. Eine vielversprechende Möglichkeit den Entscheidungsprozess über mögliche Vermeidungs- und Eliminationsmaßnahmen zu unterstützen besteht in der Priorisierung von Antibiotika entsprechend ihres Effektpotentials. Hierbei sind Substanzen zu identifizieren, die den größten Einfluss auf die Nahrungskette im Gewässer bzw. das höchste (negative) Synergiepotential mit anderen Substanzen aufweisen. Die Verringerung dieser Substanzen führt zu einer hohen ökologischen Effektivität und Effizienz der eingesetzten Mittel. Wie im Fall des klassischen Bewertungsansatzes, ist auch für den Priorisierungsansatz eine umfängliche und zuverlässige Situationsanalyse die Grundvoraussetzung für verwertbare Ergebnisse. Die Situationsanalyse beruht auf der analytischen Bestimmung bzw. der Abschätzung von emittierten Antibiotikafrachten zur Berechnung von repräsentativen Umweltkonzentrationen. Analytisch ermittelte Umweltkonzentrationen vieler Antibiotika weisen aufgrund saisonaler Verschreibungsmuster eine hohe zeitliche und räumliche Variabilität auf. Die für eine adäquate Erfassung der Situation notwendigen Messkampagnen sind kostenintensiv, wobei die tatsächlich notwendige Häufigkeit der Probenahme von zumeist nicht hinreichend bekannten substanzspezifischen Informationen, wie der chemischen Stabilität im Rohabwasser und der saisonal beeinflussten Applikation, abhängt. Alternativ können Antibiotikaeinträge in die Kanalisation anhand von Verschreibungsdaten abgeschätzt und mit Hilfe von Stoffflussanalysen (SFA) zur ökotoxikologischen Bewertung herangezogen werden. Eine vom Umfang befriedigende, direkte Gegenüberstellung von prognostizierten und analytisch ermittelten Frachten ist bisher jedoch nicht erfolgt, so dass die Verifizierung dieses Ansatzes noch aussteht. Für den Fall einer bestehenden Verschreibungspflicht für Antibiotika besitzen Verschreibungsdaten eine vergleichsweise hohe zeitliche und räumliche Informationsgüte. In Verbindung mit einer an diese Datenqualität angepassten Messkampagne, ergibt sich die Möglichkeit einer detaillierten SFA mit substanzspezifischer Bewertung der Eignung des Prognoseansatzes. Die am Beispiel der Stadt Dresden durchgeführte Bewertung des Prognoseansatzes fußt auf einer 15-monatigen Messkampagne und den für das Einzugsgebiet der Zentralkläranlage Dresden-Kaditz verfügbaren Verschreibungsdaten der AOK PLUS. Erwartungsgemäß ergibt der Abgleich von erwarteten und analytisch ermittelten Frachten eine starke Variation der für den Zulauf der Kläranlage ermittelten Wiederfindungsdaten verschiedener Substanzen. Die analytisch ermittelten Frachten von Sulfamethoxazol, Trimethoprim sowie der Gruppe der Makrolid-Antibiotika entsprechen nahezu den prognostizierten Mengen. Die Beta-Laktam-Antibiotika unterliegen bereits während des Abwassertransports einer umfänglichen, zumeist biologisch bedingten, Elimination, was zu hohen Unterbefunden im Zulauf der Kläranlage führt. Andere Substanzen hingegen (z.B. Fluorchinolone) weisen messtechnisch eine signifikante Jahresdynamik auf, die aufgrund der weitgehend konstanten Verschreibung in dieser Ausprägung nicht zu erwarten ist. Die Auswertung zuletzt genannter Substanzen zeigt deutlich, dass die Nutzung von Verschreibungsdaten nicht per se ausreicht, um die Emission von Antibiotika (und anderer Pharmazeutika) sowie die sich daraus ergebenden Umweltkonzentrationen mit ausreichender Sicherheit prognostizieren zu können. Für eine nachgelagerte ökotoxikologische Bewertung ist in diesen Fällen die Durchführung von Messungen unumgänglich. Zur effizienten Planung derartiger Kampagnen wurde der umfassende Datenpool dieser Studie hinsichtlich der erforderlichen Probenanzahl zur Bestimmung einer repräsentativen mittleren Jahresfracht ausgewertet. Es ergibt sich ein Minimum von 20 bis 40 homogen über das Jahr verteilten Proben, um die jährlich in die Kläranlage eingetragene Fracht an Antibiotika bzw. anderer Mikroschadstoffe mit ausreichender Sicherheit abschätzen zu können. Im Rahmen der SFA in der Kläranlage Dresden-Kaditz wird deutlich, dass Makrolide, Clindamycin und dessen Humanmetabolit Clindamycin-Sulfoxid sowie Trimethoprim in der nahezu keiner Elimination unterliegen, wohingegen Penizilline, Cefalosporine und auch Sulfamethoxazol teilweise bis vollständig abgebaut werden. Mit Levofloxacin und Ciprofloxacin handelt es sich um die einzigen untersuchten Antibiotika, welche zu einem signifikanten Massenanteil an Primär-, Überschuss- und Faulschlamm gebunden vorgefunden werden. Aufgrund der hohen Relevanz dieses Eliminationspfades für die zuvor genannten Antibiotika bedarf die Beobachtung von z. T. widersprüchlichen Schwankungen einer kritischen Betrachtung der Ergebnisse. Es ist nicht abschließend geklärt, ob die beobachteten Fluktuationen auf eine unzureichende Qualität der Probenahme und/oder der Analytik zurückzuführen sind oder sich die Schwankungen in einem für Faulbehälter tolerierbaren Bereich befinden. Im Anschluss an die verifizierten Antibiotikaemissionen erfolgte die Priorisierung der betrachteten Antibiotika nach ihrem ökotoxikologischen Effektpotential. Zum einen wurde der ökologische Einfluss auf verschiedene, die Nahrungskette bildende trophische Ebenen (Alge, Daphnie, Fisch) untersucht. In Anlehnung an die humanmedizinische Kombinationstherapie erfolgte im zweiten Ansatz die Beurteilung der Antibiotika hinsichtlich ihres möglichen Potentials zur Verstärkung von negativen Effekten durch das gleichzeitige Auftreten mit anderen Substanzen. Für Ciprofloxacin, Levofloxacin und die Gruppen der Makrolide und Cefalosporine konnten signifikante Beeinträchtigungen der aquatischen Umwelt nachgewiesen werden. Diese Stoffe und Stoffgruppen führten im Rahmen der untersuchten Substanzen entweder zur höchsten Schadwirkung gegenüber der niedrigsten trophischen Ebene oder besitzen das höchste Synergiepotential in Kombination mit anderen Substanzen. Die Auswertung der SFA bestätigt die grundsätzliche Eignung der Verschreibungsdaten sowie des entwickelten Prognosemodells zur Vorhersage von Antibiotikaemissionen im urbanen Raum. Die Stoffflussanalyse stellt somit ein strategisches, im Vergleich zur Messung kostengünstiges Instrument zur Identifikation von Hot Spots der Antibiotikaemission dar und erleichtert die Entscheidungsfindung für monetär aufwendige Reduktionsmaßnahmen am Ort der Entstehung oder in der Kläranlage (z.B. 4. Reinigungsstufe). Die Vorgehensweise zur Priorisierung von Substanzen hinsichtlich ihres ökotoxikologischen Effektpotentials eignet sich sehr gut, Antibiotika mit dem höchsten Schadpotential zu identifizieren. Die Verschneidung der Kenntnis dieser Substanzen mit den Ergebnissen der SFA macht deutlich, dass mit Ausnahme der Makrolide, alle ökotoxikologisch priorisierten Antibiotika eine mangelhafte Prognosefähigkeit aufweisen. Die unvollständige Abbildung kritischer Stoffströme, wie z.B. Frachtspitzen, führt insbesondere im Fall der ökotoxikologisch priorisierten Substanzen zu einer Minderung der Aussagekraft des auf Verschreibungsdaten beruhenden Prognoseansatzes. An diesem Punkt ist in zukünftigen Betrachtungen anzusetzen, um die Qualität von Verschreibungsdaten zu verbessern, potentiell nicht erfasste Emittenten in die Betrachtungen einzubeziehen, sowie die Dynamik der Rückhalte- und Eliminationsprozesse in der Kanalisation adäquat beschreiben zu können. Die ergänzende Betrachtung weiterer Anlagentechnologien (z.B. Festbettreaktoren) kann zur Bestätigung der am Beispiel der Kläranlage Dresden-Kaditz gewonnenen Ergebnisse beitragen bzw. Unterschiede bei der Elimination von Antibiotika das Potential, die Problematik der Antibiotika und anderer Mikroschadstoffe bereits während der Planung von Abwasseranlagen berücksichtigen zu können
Стилі APA, Harvard, Vancouver, ISO та ін.
21

Srivastav, Abhishek, and Spyridon Xenos. "Environmental Assessment of Kayak using MFA & LCA : A case study at Melker of Sweden." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285895.

Повний текст джерела
Анотація:
Kayaking is a watersport activity that involves paddling performed within leisure purposes. Although kayaking provides pleasure to the practitioners, there are some adverse environmental issues concerning the site used to perform kayaking due to the equipment. This paper identifies and analyzes the lifecycle stages in which negative environmental impacts are generated. Melker of Sweden is an outdoor company specialized in delivering high-quality kayaks. This study aims to present an overview of the current environmental performance of Melker of Sweden’s kayaks. For this purpose, two environmental assessment tools are applied: material flow analysis and life cycle assessment. The Material Flow Analysis (MFA) results show that the transport of material to the manufacturing unit generates a considerable amount of emissions. Additionally, hull manufacturing and assembling accessories were found to be the least resource-efficient operation among all. The Life Cycle Assessment (LCA) results identify the transport of material and the manufacturing phase as the primary sources responsible for environmental impacts. On the one hand, the use of epoxy resin and gel coat is the root cause of high contribution of the manufacturing phase. On the other hand, the use of flax fiber found to be the least contributing material to adverse environmental impacts. This report also presents a list of recommendations regarding the import of material, the efficacy of the manufacturing operations, the type of raw material, and waste treatment alternatives.
Fysisk aktivitet kan innefatta olika fritidsaktiviteter, däribland friluftsliv. Kajakpaddling är en sådan friluftslivaktivitet, alltefter utövares syfte. I denna rapport är kajakpaddling en fritidsaktivitet där där utövarens naturupplevelse främjas. Oaktat fördelarna vid utövandet av denna aktivitet kan ej förbises faktum att det också kan medföras vissa negativa konsekvenser. Denna masteruppsats har som mål att identifiera och analysera den miljöpåverkan och dennes efterspel som orsakats av en kajaks tillverkning. Melker of Sweden är ett utomhusföretag specialiserat på att leverera kajaker av hög kvalitet. I linje med företagets vision syftar denna studie till att undersöka den nuvarande miljöprestandan samt kvantifiera den potentiella miljöpåverkan från en kajaks livscykel. För detta ändamål tillämpas det två miljöbedömningsverktyg, nämligen en materialflödesanalys och livscykelanalys. Materialflödesanalysen visar att mängden av utsläpp som genereras från transporten av material till tillverkningsenheten är enorm. Utöver detta var den hulltillverkning samt den montering av tillbehörsverksamheter bland de minst resurseffektiva tillverkningssteg. Livscykelanalysen identifierar import av material och tillverkningsfas som de viktigaste källorna till miljöpåverkan. Å ena sidan är användningen av epoxiharts och gelbeläggning i tillverkningen grundorsaken till huvudbidraget. Å andra sidan är användningen av linfiber det minst bidragande material då det gäller negativa miljöeffekter. I denna studie ges rekommendationer rörande import av vissa material och materialval, sätt att öka tillverkningseffektiviteten, typ av råmaterial samt avfallsbehandlingsalternativ.
Стилі APA, Harvard, Vancouver, ISO та ін.
22

Björklund, Anna. "Environmental System Analysis of Waste Management : Experiences from Applications of the ORWARE Model." Doctoral thesis, KTH, Kemiteknik, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3055.

Повний текст джерела
Анотація:
Waste management has gone through a history of shiftingproblems, demands, and strategies over the years. In contrastto the long prevailing view that the problem could be solved byhiding or moving it, waste is now viewed as a problem rangingfrom local to global concern, and as being an integral part ofseveral sectors in society. Decisive for this view has beensociety’s increasing complexity and thus the increasingcomplexity of waste, together with a general development ofenvironmental consciousness, moving from local focus on pointemission sources, to regional and global issues of more complexnature. This thesis is about the development and application orware;a model for computer aided environmental systems analysis ofmunicipal waste management. Its origin is the hypothesis thatwidened perspectives are needed in waste managementdecision-making to avoid severe sub-optimisation ofenvironmental performance. With a strong foundation in lifecycle assessment (LCA), orware aims to cover the environmentalimpacts over the entire life cycle of waste management. It alsoperforms substance flow analysis (SFA) calculations at a ratherdetailed level of the system. Applying orware has confirmed the importance of applyingsystems perspective and of taking into account site specificdifferences in analysis and planning of waste manage-ment,rather than relying on overly simplified solutions. Somefindings can be general-ised and used as guidelines to reduceenvironmental impact of waste management. Recovery of materialand energy resources from waste generally leads to netreductions in energy use and environmental impact, because ofthe savings this brings about in other sectors. Waste treatmentwith low rate of energy and materials recovery should thereforebe avoided. The exact choice of technology however depends onwhat products can be recovered andhow they are used. Despite the complexity of the model and a certain degree ofuser unfriendliness, involved stakeholders have expressed thevalue of participating in orware case studies. It providesimproved decision-basis, but also wider understanding of thecomplexity of waste management and of environmental issues ingeneral. The thesis also contains a first suggestion of a frameworkto handle uncertainty in orware, based on a review of types ofuncertainty in LCA and tools to handle it.
QC 20100413
Стилі APA, Harvard, Vancouver, ISO та ін.
23

Stafne, Brice E. "Development and application of a two-dimensional hydrodynamic model for assessment of modern and historical flow conditions of Upper Mississippi River Pool 8 near La Crosse, Wisconsin." Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/3537.

Повний текст джерела
Анотація:
The Upper Mississippi River System (UMRS) is a diverse and dynamic ecosystem that includes the main stem river channel, side channels, backwater floodplains and lakes, islands, wetlands, grasslands, and floodplain forests. The hydrology of this rich ecosystem is one of the key drivers for physical, chemical and biological processes. However, the hydrology and hydraulics of the UMRS has been drastically altered from its natural state as a result of the construction of the locks and dams in the 1930s. Beginning with the Water Resources Development Act of 1986, biologists, ecologists, and engineers have been working to restore the river to a more natural state within the current constraints imposed by the lock and dam system. In an effort to restore rivers to a more natural state, the determination of a hydraulic reference condition is essential to understanding the "why and how" of historical river system function. Understanding the fundamental processes of historical conditions will help prioritize resources and better quantify possible outcomes for riverine restoration. The main goal of this study was to construct a hydrodynamic reference condition for Pool 8 of the Upper Mississippi River System using hydrodynamic computational fluid dynamic (CFD) modeling. The CFD model will provide a better understanding of pre-impoundment flow conditions as compared to post-impoundment conditions today. The numerical model was constructed and developed primarily from a pre-impoundment 1890s topographic map with bathymetric cross-sections in the channels. The 1890s map and other sources from the U.S. Army Corps of Engineers provided historic elevation and hydraulic reference data for model calibration. The calibrated historic model was then compared with a current model of similar scale representing post-impoundment conditions, allowing for quantitative analysis of the differences between the two conditions. Model results indicated large changes in average depth and average velocity between historic and current conditions in certain parts of the pool, while others remained relatively unchanged. For example, velocities decreased in main channel aquatic areas in the lower part of Pool 8 from an average of 0.6 m/s (2.0 ft/s) under historic conditions to 0.1 m/s (0.3 ft/s) under current conditions. In the same part of the pool, however, velocities in contiguous backwater areas remained relatively constant, with most remaining less than 0.25 m/s (0.82 ft/s). Additionally, in the lower part of the pool, discharge distribution between the floodplain areas and the main channel was historically much more dynamic, with flow concentrated in the main and secondary channels at discharges less than 2265 m3/s and in the floodplains at greater than 2265 m3/s. Under current conditions, discharge distribution is much less dynamic, with approximately 2/3 of the total discharge conveyed on the floodplain for all discharges modeled (283 m3/s to 2832 m3/s or 10,000 ft3/s to 100,000 ft3/s).
Стилі APA, Harvard, Vancouver, ISO та ін.
24

Nixdorf, Erik. "Combining measurements, remote sensing and numerical modelling to assess multi-scale flow dynamics in groundwater-dependent environmental systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-236485.

Повний текст джерела
Анотація:
Groundwater flow modelling provides an important quantitative instrument for addressing issues related to the quantity and quality of groundwater and the connected water resources. Consequently, groundwater flow models have been developed and used ubiquitously in science to deepen the understanding of subsurface processes and their drivers as well as management and planning tools. The present work investigates how numerical models can be linked to field investigations and public databases to quantitatively approach questions in the area of groundwater research. The primary goal is to develop new, efficient ways to overcome limitations of the individual hydrological concepts for solving specific hydrological problems and to increase the understanding of practical applicability of different methods. For this purpose, tailor-made approaches were developed for different study areas covering diverse spatial scales: the hydrology of a small mining lake, the riparian aquifer at the scale of a single meander as well as the aquifer systems of a large-scale river basin in China. The first part of the work deals with the physical and mathematical modelling of water constituents balance in a meromictic mining lake in Lusatia. The capability of using a rather simple mass-balance model based on a sufficient dataset of field data to evaluate lake stratification and lake-groundwater interaction were shown. In the second part, a transient numerical groundwater flow model was developed for the riparian aquifer of a stream meander and was calibrated by three different salt tracer tests. The model was used to proof the reliability of subsurface travel times derived from time series analysis and to give insights in the riparian zone dynamics during changing hydraulic gradients. The third part of the work describes the methodology to conduct risk assessment of groundwater contamination on the large catchment scale of the Songhua River in China. A comprehensive literature study was conducted to get an overview about measurement data on water quality data in China. A three-dimensional numerical flow and mass transport model was applied to access the flow and matter transport dynamics in the aquifer system of a sub-basin considering changing groundwater exploitation scenarios. Consequently, numerical groundwater modelling was combined with processed remote sensing and web mapping service data to overcome field data limitations and to derive groundwater vulnerability, groundwater hazard and groundwater risk maps for the entire Songhua River Basin. Summarizing, this doctoral thesis could develop new methods of combining field measurements, data assimilation and aggregation from various sources and groundwater modelling strategies and successfully apply these methods to find solutions on problems of multiple scales and across water systems
Die Grundwassermodellierung stellt eine wichtige wissenschaftliche Methode zur quantitativen Analyse von Fragestellungen zum Schutz der Menge und Güte der Grundwasserressourcen sowie der angeschlossenen Wasserkörper dar. Dementsprechend werden Grundwassermodelle sowohl für Planungs- und Bewertungszwecke im Wasserressourcenmanagement als auch zur wissenschaftlichen Erforschung der Prozesse im Untergrund entwickelt und angewendet. Die vorliegende Arbeit untersucht in diesem Rahmen, wie numerische Modelle, Feldmessungen und Daten generiert aus Fernerkundungsdaten und Webplattformen systematisch verknüpft werden können, um Fragestellungen im Bereich der Grundwasserforschung quantitativ zu beantworten. Das Ziel der Arbeit ist es neue effiziente Abläufe zu entwickeln, die die Limitierung der einzelnen Methoden überwinden und diese auf deren Anwendbarkeit für die Lösung spezifischer hydrologischer Probleme zu analysieren. Zu diesem Zweck wurden in dieser Doktorarbeit fallspezifische Lösungen für verschiedene Untersuchungsgebiete entwickelt, die sowohl in der räumlichen Skale als auch in den zu untersuchenden hydrologischen Fragestellungen eine große Diversität aufweisen. Im ersten Teil der Arbeit wurde die Massenbilanz von Wasserinhaltsstoffen in einem meromiktischen Tagebaurestsee im Lausitzer Revier durch physikalische und mathematische Modellierungsmethoden untersucht. Dabei konnte gezeigt werden, dass auf Basis einer gewonnenen mehrjährigen Zeitreihe von Messdaten ein einfaches Massenbilanzmodell in der Lage ist, sowohl Seeschichtungs- als auch Grundwasseraustauschdynamiken quantitativ zu beschreiben. Der zweite Teil der Arbeit umfasst die Entwicklung eines transienten numerischen Grundwassermodells für den quartären Uferaquifer im Bereich eines Flussmäanders der Selke welches anhand von Daten aus mehreren Salztracertests kalibriert wurde. Das Modell wurde dafür verwendet die transienten Verweilzeiten in der gesättigten Zone des Mäanderbogens unter dem Einfluss dynamischer hydraulischer Bedingungen zu untersuchen. Die Ergebnisse wurden im Anschluss mit Verweilzeiten verglichen, die aus der Analyse der zeitlichen Verschiebung von gemessenen elektrischen Leitfähigkeitszeitreihen zwischen Fluss und Grundwassermessstellen gewonnen wurden. Durch dieses kombinierte Verfahren konnten sowohl die Beschränkungen der zeitreihenbasierten Verweilzeitberechnung aufgezeigt als auch ein tieferes Systemverständnis für die Interaktionsdynamiken zwischen Grund- und Flusswasser auf der Mäanderskala gewonnen werden. Der dritte Teil der Arbeit beschreibt die Vorgehensweise für die Bewertung des Grundwasserkontaminationsrisikos im Einzugsgebiet des Songhua Flusses in China. Eine umfassende Literaturstudie wurde durchgeführt, um einen Überblick über die Verfügbarkeit von Messdaten zur Belastung der Wasserressourcen Chinas mit organischen Schadstoffen zu erhalten. Danach wurde für ein Teileinzugsgebiet ein dreidimensionales numerisches Grundwassermodell auf Basis der vorhandenen hydrogeologischen Daten aufgebaut. Dieses wurde dazu verwendet die Änderungen im Stofftransports und den Schadstoffkonzentrationen innerhalb des Aquifersystems unter steigenden Entnahmeraten zu analysieren. Basierend auf diesen Studien wurden auf der Skale des Gesamteinzugsgebiets, um die beschränkte Verfügbarkeit von Felddaten auszugleichen, die Ergebnisse der numerischen Grundwassermodellierung mit Fernerkundungsdaten und Webdatenbanken in einem Indexsystem kombiniert mit dem für die oberflächennahen Aquifere Vulnerabilität, Gefährdungspotential und Verschmutzungsrisiko in einer räumlichen Auflösung von 1 km² bestimmt wurden. Zusammenfassend konnten durch die vorliegende Doktorarbeit neue passgenaue Methoden zur effektiven Kombination von in-situ Messungen, der Datenerhebung und Datenintegration aus vielfältigen Datenquellen sowie numerischen Grundwassermodellierungsstrategien entwickelt und zur Lösung der untersuchten hydrologischer Fragestellen auf den verschiedenen Skalen und über die Grenzen der einzelnen hydrologischen Teilsysteme hinaus erfolgreich angewandt werden
Стилі APA, Harvard, Vancouver, ISO та ін.
25

Mollenkamp, Lorinda Larae. "Demonstrating an approach for modeling crop growth and hydrology using SWAT 2009 in Kanopolis Lake Watershed, Kansas." Kansas State University, 2013. http://hdl.handle.net/2097/16307.

Повний текст джерела
Анотація:
Master of Science
Department of Biological and Agricultural Engineering
Kyle R. Douglas-Mankin
Aleksey Y. Sheshukov
According the U.S. Environmental Protection Agency’s (EPA) website, our planet is at risk of global warming due to greenhouse gas emissions. The earth’s average temperature has been reported to have risen by 1.4°F over the last century. This seemingly small increase in average planetary temperature has been linked to devastating floods, severe heat waves, and dangerous and unpredictable shifts in our climate (US EPA, 2013a). In the 2012 report, the Intergovernmental Panel on Climate Change states that bioenergy has the potential to significantly mitigate greenhouse gases as long as this is produced in a sustainable manner (Chum, et al., 2011). In light of these facts, research into the sustainable production of bioenergy sources in the United States is currently underway. To ensure that the correct biofuel crop is selected for a given region and to investigate any secondary effects of changing our nation’s agricultural practices to include biofuels, computer models can be very useful. The Soil Water Assessment Tool (SWAT) is a robust, continuous time step model that was developed by the USDA Agricultural Resource Service that can simulate changes in land use and land management and the effect this has on erosion, water quality, and other important factors. This paper describes the preliminary work to create a model of the Kanopolis Lake Watershed that is part of the Kansas River Basin using SWAT 2009. Data pertaining to weather, topography, land use, management, stream flow, and reservoirs was gathered and incorporated into the SWAT model. This was then simulated to obtain the uncalibrated data. SWAT produced unacceptable statistics for both crop yields and for stream flow using the Nash-Sutcliffe Efficiency equation and using percent bias. This suggests that the model must be calibrated to be of use in understanding both the current and future land use scenarios. Once the model is calibrated and validated, it can be used to simulate different biofuel cropping scenarios.
Стилі APA, Harvard, Vancouver, ISO та ін.
26

Rodrigues, Dulce Buchala Bicca. "Assessment of water security using conceptual, deterministic and stochastic frameworks." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-18122014-094354/.

Повний текст джерела
Анотація:
A comprehensive assessment of water security incorporates a range of water-related concepts, since water policy issues to specific technical aspects of hydrological conditions and their interactions with societal needs and ecosystem functioning. This doctoral thesis is organized into three chapters that address such range of water security-related topics, aiming to establish a conceptual baseline and propose deterministic and stochastic accounting frameworks for a river basin water security evaluation. Specific assumptions and research questions are defined in each chapter, and are related to the management of \'Cantareira water supply system\' (located in Southeastern Brazil), focusing on different scales and on its political and hydrological aspects as well. The first chapter acts as a conceptual baseline for water security assessment, by examining general aspects of the Brazilian water policy and water allocation system. This study contrasts Brazilian and American water management systems applied to water transfer projects, discussing experiences from the \'Cantareira system\' and Colorado river basin. A deterministic accounting framework is presented in the second chapter, which is based on management of blue and green water kinds (defined in accordance with hydrological processes and storage types), and demonstrates how a quantitative analysis of provisioning and use (abstraction and consumption) of both water kinds can be conducted. An agricultural basin (291 km²) within the Cantareira water supply system (located upstream of the Cachoeira reservoir) was used to illustrate this approach. The impact of blue and green water use on median water resources conditions is accounted by the scarcity indicator, while the vulnerability indicator considers the probability of low availability of water resources. In the third chapter quantifies and discusses the impacts of uncertainties on water security indicators (proposed in the chapter 2), based on a multi-model and resampling framework, that considers several uncertainty sources including those related to: i) observed streamflow data; ii) hydrological model structure; iii) residual analysis; iv) Environmental Flow Requirement methods; v) the definition of critical conditions for water provision; and vi) the critical demand imposed by human activities. Then, the uncertainty is propagated through different methodological arrangements applied to the same study basin of chapter 2. In brief, the first chapter indicates that both Brazilian and American water management system can potentially contribute to each other. In the second chapter, the Blue/Green water-based accounting framework reveal clear spatial and temporal patterns of water scarcity and vulnerability levels within the basin, thereby improving our understanding of how and where water-related threats to human and aquatic ecosystem security can arise (so called hot-spots). The third chapter provide a general method that can form basis for meaningful support to end-users facing water resource challenges by enabling them to incorporate a viable uncertainty analysis into a robust decision making process. Further investigation are proposed in each research step of this doctoral thesis.
A avaliação da segurança hídrica pode incorporar vários conceitos relacionados à água, desde aspectos da política de recursos hídricos até questões hidrológicas específicas e suas interações com a sociedade e ecossistemas. Esta tese de doutorado busca estabelecer uma base conceitual e propor esquemas metodológicos com base determinística e estocástica para avaliação da segurança hídrica de bacias hidrográficas. Objetivos específicos são definidos em cada capítulo e relacionam-se à gestão do \'Sistema Cantareira de abastecimento de água\' (localizado no Sudeste do Brasil), com foco em diferentes escalas, bem como aspectos políticos e hidrológicos. O primeiro capítulo é apresentado como baseline conceitual, examinando aspectos gerais da política de recursos hídricos e sistemas alocação de água. Este estudo compara sistemas de gestão aplicados a projetos de transposição de água inter/intra-bacias no Brasil e Estados Unidos, discutindo experiências do Sistema Cantareira e da bacia do rio Colorado. O segundo capítulo, por sua vez, propõe e analisa um esquema metodológico determinístico baseado na gestão das águas azul e verde (definidas de acordo com processos hidrológicos e unidades de armazenamento). Este estudo demonstra como uma análise quantitativa da provisão e utilização de ambos os tipos de água pode ser conduzida, propondo indicadores de escassez e vulnerabilidade hídrica. Esta abordagem foi aplicada em uma bacia agrícola (291 km²), localizada a montante do reservatório Cachoeira, que é integrante do Sistema Cantareira. O terceiro capítulo quantifica e analisa os impactos das incertezas sobre os indicadores de segurança hídrica propostos no capítulo 2, utilizando um esquema metodológico estocástico baseado em múltiplos modelos e reamostragem, que incorpora variadas fontes de incerteza, tais como: i) dados observados de vazão; ii) estrutura do modelo hidrológico; iii) análise de resíduos do modelo hidrológico; iv) estimativa de vazão ambiental; v) definição de condições críticas de provisão e vi) demanda hídrica. Em seguida, as incertezas são propagadas através de diferentes arranjos metodológicos aplicados na mesma bacia estudo do capítulo 2. Em conclusão, o primeiro capítulo sugere uma potencial troca de contribuições provenientes de ambos os sistemas de gestão brasileiro e americano. O segundo capítulo revela padrões espaciais e temporais dos resultados dos indicadores de escassez e vulnerabilidade, melhorando assim a compreensão de como e onde ameaças à segurança hídrica podem surgir. Por sua vez, a análise de incertezas desenvolvida no terceiro capítulo é capaz de gerar suporte a gestores de recursos hídricos e processo de tomada de decisões robustas. Recomendações específicas são geradas em cada capítulo da presente tese de doutorado.
Стилі APA, Harvard, Vancouver, ISO та ін.
27

Iwalewa, Tajudeen. "Coupling source term, mineral reactivity and flow in radionuclide transport." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/265633.

Повний текст джерела
Анотація:
The focus of this work is to investigate the dissolution of MW25, a non-radioactive simulant of UK high-level nuclear waste borosilicate glass, and to predict its performance in the near field of a geological repository. A single-pass flow-through (SPFT) experimental system was used to measure the forward dissolution rates of MW25. Experiments were conducted in two parts. Experiment Part 1 considers the dissolution of the waste glass in deionised water at 40 and 90 oC and circum-neutral pH. Experiment Part 2 considers the dissolution of the waste glass in simulant groundwaters, with similar compositions to groundwaters of Callovo-Oxfordian clay (lower-strength sedimentary rock (LSSR)) and Borrowdale Volcanic Group rocks (higher-strength rock (HSR)), at 40 oC and pH 7. The forward dissolution rate measured in deionised water was found to be approximately one order of magnitude higher at 90 oC than at 40 oC. A similar release was observed for Si, Mg and Al at 40 oC and 90 oC, whereas the B, Cs, Na, Li and Mo showed an order of magnitude increase when the temperature was increased from 40 to 90 oC for low q/S values. The activation energy (Ea) of the reactions shows that the dissolution process is a surface phenomenon. At 90 oC the net effect of the processes governing MW25 dissolution led to the preferential release of boron and alkali metals relative to the release of Si during the transient dissolution stage, accompanied by an increase in the concentration of silicic acid. This suggests that the solution activity of silicic acid at a higher temperature has a weak influence on the release of the mobile elements. The forward dissolution rate measured in LSSR simulant groundwater was found to be slightly higher than that measured in HSR simulant groundwater. The dissolution behaviour of MW25 in both groundwaters is consistent with its behaviour in deionised water at 40 oC, with the dissolution rates of elements increasing as flow rates were increased. However, forward dissolution rates measured in the simulant groundwaters were lower than the forward dissolution rates measured in deionised water under these experimental conditions. This is attributable to the interaction of the components of the simulant groundwaters with the glass, as revealed by post-reaction surface analyses, and a consequential lower alkalinity of the leachates collected in the experiments with simulant groundwater than in deionised water. Reactive chemical transport simulations of waste glass dissolution and radionuclide release in a hypothetical near field were conducted over a time span of a million years with GoldSim. The results showed that enclosing the waste glass in a steel canister covered by a copper canister and emplacing the waste package in a granite host rock is optimal for the long-term isolation of the radionuclides. The waste glass was found to play a significant role in the overall performance of the near field. This study features a new method for estimating the surface area of reacted glass powder more accurately than the geometric surface area estimate, which is the preferred standard method among researchers.
Стилі APA, Harvard, Vancouver, ISO та ін.
28

Papageorgiou, Asterios. "Emerging technologies for climate-neutral urban areas : An Industrial Ecology perspective." Licentiate thesis, KTH, Resurser, energi och infrastruktur, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292648.

Повний текст джерела
Анотація:
The ever-increasing concentration of human activity in urban areas induces environmental problems beyond their boundaries on scales ranging from local to regional to global, such as resource depletion, land degradation, air and water pollution and climate change. Human-induced climate change is widely acknowledged as one of the greatest sustainability challenges of the present century and it is inextricably linked to urbanization. As a response to climate change, urban areas around the world have committed to reach climate neutrality within the next decades. In this context, the deployment of new technologies can have a key role in achieving carbon neutrality in urban areas. As new technologies emerge, it is essential to assess their environmental performance considering the broader systems context in order to ensure that they can indeed contribute to achieving climate neutrality without compromising environmental sustainability. This thesis aims is to provide insight on the environmental performance of emerging technologies that can be deployed in urban areas in order to contribute to achieving climate neutrality. The two technologies in focus are grid-connected solar microgrids and biochar-based systems for treatment of biomass waste and remediation of contaminated soil. The methods applied to conduct the environmental assessments and fulfil the aim of the thesis are: case studies, Life Cycle Assessment (LCA), Material and Energy Flow Analysis and Substance Flow Analysis. Moreover, as part of the research efforts, a spreadsheet model based on LCA data was developed. The assessment of the solar microgrid highlighted the importance of using explicit spatial and temporal boundaries when analyzing the environmental performance of energy systems, as it can increase the accuracy of the results. It also revealed that the choice of modeling approach can influence the results of the assessment, which motivates the application of different methodological approaches. Within this context, the assessment showed that in a short-term perspective the integration of a grid-connected urban solar microgrid into the Swedish electricity grid would not contribute to climate change mitigation, as solar electricity from the microgrid would displace grid electricity with lower carbon intensity. The assessment also indicated that operational and structural changes in the microgrid could reduce its climate change impact, albeit not to the extent to generate GHG emission abatements. The assessment of the biochar-based systems showed that these systems have many environmental benefits compared to incineration of waste and landfilling of contaminated soil. They have great potential to contribute to achieving climate neutrality, as they can provide net negative GHG emissions, owing mainly to carbon sequestration in the biochar. Between the two biochar-based systems, a system for on-site remediation can provide additional environmental benefits, as it can lead to more efficient use of resources. However, these systems also entail environmental trade-offs due to increased consumption of auxiliary electricity, while the extent of ecological and human health risks associated with the reuse of biochar-remediated soils is for the moment unknown.
Den ständigt ökande koncentrationen av mänsklig aktivitet i urbana områden orsakar miljöproblem utanför deras gränser på skalor som sträcker sig från lokal till regional till global, såsom utarmning av resurser, markförstöring, luft- och vattenföroreningar och klimatförändring. Mänskligt driven klimatförändring är allmänt erkänd som en av de största hållbarhetsutmaningarna under nuvarande seklet och den är nära kopplad till urbanisering. Som ett svar på klimatförändringen har urbana områden runt om i världen åtagit sig att nå klimatneutralitet inom de närmaste decennierna. I detta sammanhang kommer införandet av ny teknik ha en nyckelroll för att uppnå klimatneutralitet i stadsområden. När ny teknik dyker upp är det viktigt att bedöma dess miljöprestanda med hänsyn till den bredare systemkontexten för att säkerställa att tekniken verkligen kan bidra till att uppnå klimatneutralitet utan att kompromissa med miljömässig hållbarhet. Denna avhandling syftar till att ge insikt om miljöprestanda för framväxande teknik som kan användas i urbana områden för att bidra till att uppnå klimatneutralitet. De två teknikerna i fokus är nätanslutna solmikronät och biokolbaserade system för behandling av biomassavfall och sanering av förorenad mark. Metoderna för att genomföra miljöbedömningarna och uppfylla avhandlingens syfte är: fallstudier, livscykelanalys (LCA), material- och energiflödesanalys och substansflödesanalys. Som en del av forskningsinsatserna utvecklades dessutom en kalkylmodell baserad på LCA-data. Analysen av solmikronätet visade att det är viktigt att använda explicita rums- och tidsgränser vid analys av energisystemens miljöprestanda, eftersom det kan öka resultatens noggrannhet. Analysen visade också att valet av modelleringsmetod kan påverka resultatet, vilket motiverar en användning  av flera olika metoder. Inom detta sammanhang visade bedömningen att i ett kortsiktigt perspektiv skulle integrationen av ett nätanslutet urbant solmikronät i det svenska elnätet inte bidra till att begränsa klimatförändringen, eftersom solenergi från mikronätet skulle ersätta el med lägre klimatpåverkan. Bedömningen indikerade också att operativa och strukturella förändringar i mikronätet kunde minska mikronätets klimatförändrings påverkan, om än inte i sådan utsträckning att det skulle ge växthusgasutsläppsbesparingar. Bedömningen av de biokolbaserade systemen visade att dessa system har många miljöfördelar jämfört med förbränning av avfall och deponering av förorenad mark. De har stor potential att bidra till att uppnå klimatneutralitet, eftersom de kan ge nettonegativa utsläpp av växthusgaser, främst på grund av kolbindning i biokol. Vi jämförelse av de två biokolbaserade systemen så kan ett system för sanering på plats ge ytterligare miljöfördelar, eftersom det kan leda till en mer effektiv resursanvändning. Dessa system medför emellertid också miljöavvägningar på grund av ökad förbrukning av elektricitet, medan omfattningen av ekologiska och människors hälsorisker förknippade med återanvändning av biokolbehandlad jord ännu är okända.

QC 20210419

Стилі APA, Harvard, Vancouver, ISO та ін.
29

Abbatelli, Daniele. "Material flows in the waterjet industry : an environmental perspective." Thesis, Linköpings universitet, Industriell miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-111003.

Повний текст джерела
Анотація:
Abrasive Waterjet cutting (AWJ) presents many advantages over competing machining techniques, but several issues are related to the high volume of materials (and in particular of abrasive) used in the process. In this study, the environmental impact of the material flows in the abrasive waterjet industry has been analyzed adopting a life cycle perspective in order to individuate which phases place the largest burden on the environment. Moreover, three alternative abrasives (crushed rock, recycled glass and synthetic abrasive) and three disposal practices (in-site recycling, off-site recycling and recycling as construction material) have been also evaluated to estimate the benefits that can be achieved if these could be used in place of garnet abrasives and landfilling. The transportation of the abrasive resulted to be the phase that has the largest influence in every case and thus should be reduced as much as possible. For what concerns the alternative options, the usage of recycled glass and the in-site recycling of the abrasive were the two alternatives with the best environmental performances. However, crushed rock could be the best option for what concerns the global warming potential if carbon sequestration due to carbonation of silicate rocks is taken into account. Off-site recycling and recycling as construction material are good options only if the transportation to the recycling site can be reduced. Synthetic abrasive are instead found to have a much larger impact compared to every other alternative examined.
Стилі APA, Harvard, Vancouver, ISO та ін.
30

Kvapilová, Jana. "Sledování environmentálních nákladů v Kovohutích Příbram nástupnická, a.s." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2009. http://www.nusl.cz/ntk/nusl-222334.

Повний текст джерела
Анотація:
Environmental managerial accounting is one of voluntary tools of environmental policy. It helps company to recognize its influence on environment and it is a base for environmental management decision-making, which brings environmental and economical results. EMA consists from two parts. The first is input/output balance of materials and energies and the second is a statement of environmental costs and revenues. Environmental accounting evaluates financial and physical information. Statements show in which domain there is the biggest influence on environment. Target of this work has been to implement this accounting in the company Kovohutě Příbram nástupnická, a.s. It is a long process, which needs cooperation of many employees of company. In the process of identification of environmental costs there were defined facilities, which protect or injure environment. Costs with influence on environment were described as environmental costs. On the base of environmental statements company is able to make decisions, which will lead to cleaner production
Стилі APA, Harvard, Vancouver, ISO та ін.
31

Grimaud, Guilhem. "conception des scénarios de recyclage pilotée par l’évaluation des performances des procédés." Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0005/document.

Повний текст джерела
Анотація:
La planète se trouve dans un état de dégradation des écosystèmes, d’épuisement des ressources, de tension démographique et d’urgence climatique particulièrement préoccupant. Le découplage de la consommation de matières premières avec l’activité économique est indispensable. En réduisant la pression sur la raréfaction des matières premières, l’économie circulaire peut participer à la lutte contre le dérèglement climatique. Bien que le recyclage ne puisse solutionner seul l’épuisement des ressources, il est indispensable de mettre en œuvre des solutions pour régénérer les matières présentes dans nos déchets. Or l’organisation actuelle de la filière de fin de vie ne semble pas répondre aux besoins de l’économie-monde.Le premier challenge pour déployer des solutions de recyclage en économie circulaire repose sur l’évaluation de la performance des scénarios de recyclage. La méthodologie proposée repose sur plusieurs outils d’analyse : analyse de flux de matières (MFA), Analyse de Cycle de Vie (ACV) et Analyse de coûts (LCC) dans un cadre technique de référence basé sur l’évaluation des écotechnologies (ETV). Ce travail s’applique en partenariat avec la société MTB. Trois axes de performances ont été retenus : technique, économique et environnemental.Cette évaluation multicritères, intégrés dans la démarche de conception de MTB, permet une communication sous la forme d’indicateurs clés de performances (KPI). Ces indicateurs supplémentaires permettent de quantifier rapidement l’éco-efficience d’un scénario, pour accompagner la prise de décisions des concepteurs lors de la construction de l'offre et du développement des solutions scénarios de recyclage
The planet is in a particularly worrying state of degradation of ecosystems, depletion of resources, demographic tension and a climate emergency. The decoupling of the consumption of raw materials with economic activity is a relevant action lever. By reducing the pressure on the scarcity of raw materials, the circular economy can participate in the fight against climate change. Although recycling alone cannot solve resource depletion, it is essential to implement solutions to regenerate the materials present in our waste. However, the current organization of the end-of-life sector does not seem to meet the needs of the world economy.The first challenge in deploying recycling solutions in the circular economy is based on evaluating the performance of recycling scenarios. The proposed methodology is based on several analytical tools: Material Flow Analysis (MFA), Life Cycle Assessment (LCA) and Life Cost Costing (LCC) in a technical reference framework based on the evaluation of environmental technologies (ETV). This work applies in partnership with the company MTB. Three performance axes were chosen: technical, economic and environmental.This multi-criterion assessment, integrated into the MTB design process, allows communication in the form of key performance indicators (KPI). By providing additional performance indicators it is possible to quickly quantify the eco-efficiency, to support decision-making by designers during the development of the recycling pathway
Стилі APA, Harvard, Vancouver, ISO та ін.
32

Youhanan, Lena. "Environmental Assessment of Textile Material Recovery Techniques : Examining Textile Flows in Sweden." Thesis, KTH, Industriell ekologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-123770.

Повний текст джерела
Анотація:
The production of textiles, focusing on cotton and polyester, carries with it major environmental concerns such as significant water and chemical use as well as the use of non-renewable resources. Measures need to be taken to decrease those environmental burdens. The present study investigates four different recovery techniques in terms of specific environmental factors. The investigated recovery methods are the Re:newcell method, polyester recycling, textile to insulation material and biogas production from the digestion of textile waste. Incineration is also included as a reference alternative. Waste flows in Sweden are estimated through a literature review of conducted waste analyses and estimations as to the amount of secondary product that can be produced from that input are duly made. Further, the environmental implications of three potential locations for a sorting facility are investigated. Converting cotton into biogas was found to be an unrealistic approach since it is economically inviable and little or no energy is actually gained when transportation costs are taken into consideration. Further studies on the benefits and costs of recycling cotton into insulation material are needed. The unavoidable transportation related to collection, sorting and recycling are not to be underestimated and could in some cases hinder future environmental improvements.  Finally, the study found that fiber material recycling is the only treatment method that has the potential to decrease the environmental burdens related to primary production although, despite the fact it requires the most water and chemicals. However, the data reliability in the current study is a matter of concern and further research in the form of standardized data collection and the use of analytical and strategic tools in further assessments is recommended. Although the recovery of textile material is crucial for decreasing the environmental burdens from primary production of textiles, the work in preventing textile waste is even more vital. In the long run, the prevention of waste is far more important as recovery processes demands their own share of resources.
Den primära produktionen av textilier för med sig enorma miljömässiga påfrestningar. Omfattande mängder kemikalier och vatten samt icke-förnybara resurser används vid tillverkningen av bomull och polyester. Det är nödvändigt att vidta åtgärder för att minska dessa negativa effekter på miljön. Denna studie syftar till att undersöka fyra olika återvinningstekniker för textilt avfall med fokus på bomull och polyester. Förbränning med energiutvinning inkluderas som ett referensfall och återvinningsteknikerna jämförs med hjälp av utvalda miljöfaktorer. De återvinningstekniker som jämförs är Re:newcells metod för återvinning av bomull (och andra cellulosa material) till viskosfiber, kemisk polyesteråtervinning, återvinning av bomull till isoleringsmaterial för byggnader samt rötning av bomullstextilier för utvinning av biogas. Avfallsströmmarna i Sverige uppskattas med hjälp av litteraturstudier av framförallt genomförda plockanalyser. Alla faktorer jämförs med avseende på 1 ton blandat textilavfall från hushåll i Sverige och hur mycket av det som kan användas som potentiell råvara i återvinningsprocesserna. Vidare undersöks även de miljömässiga effekterna som uppstår vid transport av det textila avfallet till en sorteringsanläggning och till återvinnigsanläggningar. Tre potentiella placeringar av sorteringsanläggningen undersöks: Stockholm, Vänersborg och Wolfen, Tyskland. Studien fann att endast fibermaterialåtervinning har möjlighet att motverka de miljömässiga påfrestningarna från primärproduktionen även om de också innebär den största användningen av resurser såsom vatten och kemikalier. Rötning av bomull till biogas anses vara ett orealistiskt alternativ då metoden är ekonomiskt oförsvarbar och lite eller ingen energi egentligen utvinns när man inkluderar de nödvändiga transporterna. Vidare studier behövs för att uppskatta nyttan och kostnaderna för återvinning av bomull till isoleringsmaterial. De transporter som oundvikligt behövs vid återvinning pga. insamling, sortering och återvinning bör inte underskattas och kan i vissa fall förhindra att miljönyttan ökar. Resultaten i studien bör däremot användas kritiskt då tillförlitligheten i det data som har använts i vissa fall kan ifrågasättas. Detta beror på att många antaganden och uppskattningar har gjorts pga. brist på data av sekretesskäl. Mer forskning och undersökningar rekommenderas i form av standardiserade metoder för plockanalyser av textilt avfall. Användningen av analytiska och strategiska verktyg såsom LCA och EIA/SEA rekommenderas för att ta hänsyn till alla intressenter vad gäller end-of-life för textilt avfall. Fastän återvinning är en nödvändig del i arbetet att minska på de miljömässiga påfrestningarna som primärproduktion bidrar till är det ännu viktigare att arbeta med åtgärder för att minska avfallet. Återvinning kräver sin andel resurser i from av energi, vatten och kemikalier bland annat.
Стилі APA, Harvard, Vancouver, ISO та ін.
33

Quinteiro, Paula Sofia Gil Neto. "Environmental impacts of freshwater use and suspended solids in life cycle assessment." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15734.

Повний текст джерела
Анотація:
Doutoramento em Ciências e Engenharia do Ambiente
Perturbation of natural ecosystems, namely by increasing freshwater use and its degradative use, as well as topsoil erosion by water of land-use production systems, have been emerging as topics of high environmental concern. Freshwater use has become a focus of attention in the last few years for all stakeholders involved in the production of goods, mainly agro-industrial and forest-based products, which are freshwater-intensive consumers, requiring large inputs of green and blue water. This thesis presents a global review on the available Water Footprint Assessment and Life Cycle Assessment (LCA)-based methods for measuring and assessing the environmental relevance of freshwater resources use, based on a life cycle perspective. Using some of the available midpoint LCA-based methods, the freshwater use-related impacts of a Portuguese wine (white ‘vinho verde’) were assessed. However, the relevance of environmental green water has been neglected because of the absence of a comprehensive impact assessment method associated with green water flows. To overcome this constraint, this thesis helps to improve and enhance the LCA-based methods by providing a midpoint and spatially explicit Life Cycle Impact Assessment (LCIA) method for assessing impacts on terrestrial green water flow and addressing reductions in surface blue water production caused by reductions in surface runoff due to land-use production systems. The applicability of the proposed method is illustrated by a case study on Eucalyptus globulus conducted in Portugal, as the growth of short rotation forestry is largely dependent on local precipitation. Topsoil erosion by water has been characterised as one of the most upsetting problems for rivers. Because of this, this thesis also focuses on the ecosystem impacts caused by suspended solids (SS) from topsoil erosion that reach freshwater systems. A framework to conduct a spatially distributed SS delivery to freshwater streams and a fate and effect LCIA method to derive site-specific characterisation factors (CFs) for endpoint damage on aquatic ecosystem diversity, namely on algae, macrophyte, and macroinvertebrates organisms, were developed. The applicability of this framework, combined with the derived site-specific CFs, is shown by conducting a case study on E. globulus stands located in Portugal as an example of a land use based system. A spatially explicit LCA assessment was shown to be necessary, since the impacts associated with both green water flows and SS vary greatly as a function of spatial location.
As perturbações no equilíbrio dos ecossistemas devido ao aumento do uso de água doce, do aumento da sua poluição, e da erosão do solo pela água, são temas emergentes e de elevada significância na avaliação da sustentabilidade. Na presente tese é efetuada uma revisão de literatura dos métodos desenvolvidos para contabilizar e avaliar os impactes do uso de água doce, numa perspetiva de ciclo de vida. O método da pegada de água desenvolvido pela Water Footprint Network, e os vários métodos desenvolvidos com base na metodologia de Avaliação de Ciclo de Vida (ACV) foram analisados. Os impactes decorrentes do uso de água para a produção do vinho verde branco produzido em Portugal, foram contabilizados e avaliados, por aplicação de alguns destes métodos de ACV. A relevância da água verde na regulação dos serviços do ecossistema tem sido ‘esquecida’ devido à ausência de um método capaz de avaliar os impactes ambientais decorrentes de alterações dos fluxos de água verde. Para superar esta lacuna, na presente tese é apresentado um método de Avaliação de impacte do Ciclo de (AICV) midpoint que permite uma avaliação espacialmente diferenciada dos impactes decorrentes das alterações dos fluxos de água verde que retornam à atmosfera em resultado de atividades de uso de solo. Este método permite também uma avaliação da redução de produção de água azul devido a reduções no escoamento superficial. A aplicabilidade deste método é demonstrada num caso de estudo de povoamentos de Eucalyptus globulus localizados em Portugal, os quais dependem fortemente da precipitação local. A erosão do solo pela água afeta os ecossistemas aquáticos, nomeadamente quando os sólidos suspensos (SS) atingem os rios. Na presente tese foi desenvolvida uma abordagem para estabelecer inventários de SS espacialmente diferenciados, e um método de AICV endpoint que permite obter fatores de caracterização específicos para avaliar os impactes ambientais diretos dos SS em algas, macrófitas e macroinvertebrados. A aplicabilidade da abordagem de inventário e do método endpoint foi demonstrada num caso de estudo de povoamentos de E. globulus localizados em Portugal. Tanto os impactes associados aos fluxos de água verde como os impactes relativos aos SS variam significativamente em função da localização do sistema de uso de solo em análise, pelo que se conclui que a inclusão da variabilidade espacial deve ser considerada em métodos de ACV.
Стилі APA, Harvard, Vancouver, ISO та ін.
34

Damons, Matthew. "An assessment of the contribution of surface and subsurface flows to river flows of the Sandspruit in the Berg River Catchment, South Africa." University of the Western Cape, 2018. http://hdl.handle.net/11394/6415.

Повний текст джерела
Анотація:
Magister Scientiae - MSc (Environ & Water Science)
Studies have shown that the primary origin of salinity in river flows of the Sandspruit in the Berg Catchment located in the Western Cape Province of South Africa was mainly a result of atmospheric deposition of salts. The salts are transported to rivers through surface runoff and subsurface flow (i.e. through flow and groundwater flow). The purpose of this study was to determine the contributions of subsurface and surface flows to the total flows in the Sandspruit, Berg Catchment. Three rain events were studied. Water samples for two rain events were analysed for environmental tracers ?18O, Silica or Silicon dioxide (SiO2), Calcium (Ca2+) and Magnesium (Mg2+). Tracers used for two component hydrograph separation were ?18O and SiO2. The tracers, Ca2+ and Mg2+, revealed inconsistent contributions of both subsurface flow and surface flow. Two component hydrograph separations indicated is that groundwater is the dominant contributor to flow, while surface runoff mainly contributes during the onset of the storm event. Groundwater response to precipitation input indicated that boreholes near the river have a quicker response than boreholes further away from the river. Boreholes nearer to the river also indicate higher water levels in response to precipitation, in comparison to boreholes further from the river.
Стилі APA, Harvard, Vancouver, ISO та ін.
35

Papafragrou, Anastasios. "Urban carbon and energy analysis : calculation of energy flows and emissions from residential housing clusters and assessment of sustainable energy options." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/210375/.

Повний текст джерела
Анотація:
In the UK, the domestic sector accounts for around 30% of fuel-use and energy related carbon emissions, and therefore has the potential to deliver significant reductions in carbon dioxide emissions. The purpose of this work is to form and examine various heat and electricity supply scenarios at the street-level and identify which of these scenarios offer the most potential to reduce consumption of resources and carbon dioxide emissions. The path to realisation of a reduction in carbon emissions from the domestic sector incorporates three consecutive steps: (1) saving energy, (2) use of renewables and (3) use energy as efficiently as possible, including fossil fuels. In reality, there is a strong interaction between all three steps and often they take place simultaneously. The first two steps tend to minimise the use of fossil fuels, but not to eliminate them. In this work it is recognised that in mature urban regions fossil fuels cannot be readily displaced completely, but can be used in a more efficient way. This research considers what can be achieved by applying at or near to market technologies at the street level microgrid scale, such as Combined Heat and Power (CHP). The renewable energy technologies considered were photovoltaics (PV) for electricity generation, solar thermal for domestic hot water heating and ground source heat pumps (GSHP) for space heating. For the development of the models, the transient simulation package TRNSYS was used and a residential area in Southampton that represents a typical UK area, was chosen as a case study. The notion of combining a number of houses to form a local microgrid proved to be beneficial for all the technologies examined in this research. It was shown that renewable energy microtechnologies can improve their carbon performance up to 10% when operating as a microgrid, whilst estimated benefits were even greater for CHP systems. Parallel operation strategies were also investigated and it was shown that they have the potential to deliver further savings from microgrid schemes. Microgrids, although their high capital costs, were estimated to have better financial performance compared with the single house level for many of the cases examined. Increased generation and lower heating demand were the key outcomes due to the impact of change in climate
Стилі APA, Harvard, Vancouver, ISO та ін.
36

He, Ding. "Application of Biomarkers and Compound Specific Stable Isotopes for the Assessment of Hydrology as a Driver of Organic Matter Dynamics in the Everglades Ecosystem." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1569.

Повний текст джерела
Анотація:
The Everglades is a sub-tropical coastal wetland characterized among others by its hydrological features and deposits of peat. Formation and preservation of organic matter in soils and sediments in this wetland ecosystem is critical for its sustainability and hydrological processes are important divers in the origin, transport and fate of organic matter. With this in mind, organic matter dynamics in the greater Florida Everglades was studied though various organic geochemistry techniques, especially biomarkers, bulk and compound specific δ13C and δD isotope analysis. The main objectives were focused on how different hydrological regimes in this ecosystem control organic matter dynamics, such as the mobilization of particulate organic matter (POM) in freshwater marshes and estuaries, and how organic geochemistry techniques can be applied to reconstruct Everglades paleo-hydrology. For this purpose organic matter in typical vegetation, floc, surface soils, soil cores, and estuarine suspended particulates were characterized in samples selected along hydrological gradients in the Water Conservation Area 3, Shark River Slough and Taylor Slough. This research focused on three general themes: (1) Assessment of the environmental dynamics and source-specific particulate organic carbon export in a mangrove-dominated estuary. (2) Assessment of the origin, transport and fate of organic matter in freshwater marsh. (3) Assessment of historical changes in hydrological conditions in the Everglades (paleo-hydrology) though biomarkes and compound specific isotope analyses. This study reports the first estimate of particulate organic carbon loss from mangrove ecosystems in the Everglades, provides evidence for particulate organic matter transport with regards to the formation of ridge and slough landscapes in the Everglades, and demonstrates the applicability of the combined biomarker and compound-specific stable isotope approach as a means to generate paleohydrological data in wetlands. The data suggests that: (1) Carbon loss from mangrove estuaries is roughly split 50/50 between dissolved and particulate carbon; (2) hydrological remobilization of particulate organic matter from slough to ridge environments may play an important role in the maintenance of the Everglades freshwater landscape; and (3) Historical changes in hydrology have resulted in significant vegetation shifts from historical slough type vegetation to present ridge type vegetation.
Стилі APA, Harvard, Vancouver, ISO та ін.
37

FERRONATO, GIULIA. "Valutazione dell'impatto ambientale a diversi livelli di scala del settore zootecnico." Doctoral thesis, Università Cattolica del Sacro Cuore, 2020. http://hdl.handle.net/10280/72497.

Повний текст джерела
Анотація:
Negli ultimi tre decenni la domanda globale di cibo, in particolare di proteine animali (carne, latte, uova), è aumentata in base alla crescita della popolazione che dovrebbe arrivare a 9 miliardi di persone entro il 2050. Questi alimenti rappresentano infatti un'importante fonte di energia, proteine di alta qualità, micronutrienti e vitamine. Pertanto, questo miglioramento potrebbe contribuire all'aumento della durata della vita e della domanda di cibo. Ciò ha costretto il settore agricolo ad un'ulteriore intensificazione che ha interessato anche la coltivazione di colture per l'alimentazione animale. Le produzioni agricole e zootecniche hanno un impatto ambientale rilevante, e questo argomento è oggetto di critiche e di indagini scientifiche anche per definire più accuratamente il loro contributo e le relative potenziali strategie di mitigazione, considerando anche che la fase agricola è il principale contributore dell'impatto ambientale della catena di produzione alimentare. Si riconosce infatti che il settore agricolo contribuisce direttamente al 21% delle emissioni totali di gas serra di origine antropica a livello mondiale e consiste per lo più di metano seguito da protossido di azoto e anidride carbonica. Queste emissioni sono per lo più associate alla produzione zootecnica, in particolare all'allevamento di ruminanti che contribuisce con le emissioni dirette di metano dovute alla fermentazione dei ruminanti e alla fermentazione del letame; la restante parte è composta da emissioni indirette dovute alla deforestazione, all'uso di energia e alla produzione di mangimi. Lo scopo di questa tesi è stato la valutazione dell'impronta ambientale nel settore zootecnico a diversi livelli di scala tematica. La filiera italiana della carne, gli allevamenti lattiero-caseari, un caseificio per la produzione di Grana Padano DOP e i singoli animali sono stati studiati per quantificare l'impronta ambientale. Nel primo lavoro è stata valutata la filiera italiana della carne con un approccio di analisi dei flussi di massa e di valutazione del ciclo di vita. In primo luogo, la quantificazione della carne è stata effettuata dalla macellazione al consumo domestico, partendo dal peso della carcassa fino alla carne realmente consumata. A questo livello si è tenuto conto della carne di bovini, suini, ovini e caprini, equidi e conigli. Durante la catena sono state quantificate anche le perdite di carne e i rifiuti. In particolare, i sottoprodotti di origine animale (SOA) sono stati quantificati per singole specie e classificati in base al rischio a livello sanitario secondo il regolamento (CE) 1069/2009. Secondo la categoria (Cat 1, Cat 2 o Cat 3), supponendo che tutti i SOA fossero destinati al processo di rendering, l'uso e lo smaltimento dei prodotti dopo rendering è stato identificato. L'analisi dei flussi di massa ha confermato come l'Italia sia un importatore netto di carne bovina e suina, mentre è autosufficiente per quanto la carne avicola. L'analisi dei flussi di massa rivela che nel 2013 sono stati consumati in Italia 2,86 Mt di carne. Questo valore equivale a 131 g/giorno/pro-capite e a 47,91 kg/anno/pro-capite di carne consumata. In percentuale la quantità totale di carne consumata è rappresentata dal 46% da carne suina, dal 28% di carne avicola, dal 23% di carne bovina e dal 3% di altre carni (coniglio, equini, ovini e caprini). Questo approccio ha permesso di quantificare anche sottoprodotti di origine animale (SOA) prodotti durante la fase di macellazione e gli scarti alimentari a livello di vendita al dettaglio e fase di consumo. La fase di macellazione è risultata essere la principale fonte di rifiuti, producendo il 48% di rifiuti originati nella filiera della carne. I risultati hanno evidenziato come i SOA siano già quasi completamente riutilizzati, compatibilmente con il loro rischio a livello sanitario, dimostrando la circolarità del sistema e permettendo di quantificare anche i prodotti evitati grazie al loro riutilizzo e le relative emissioni di gas serra evitate. Per quanto riguarda gli altri rifiuti alimentari, i risultati della presente valutazione possono essere considerati solo una stima per la mancanza di specifici coefficienti nazionali. Dopo la fase di quantificazione, è stato applicato l'approccio del Life Cycle Assessment (LCA) per valutare l'impronta ambientale, considerando anche il prodotto evitato grazie al riutilizzo dei sottoprodotti del rendering. I risultati dell'LCA rivelano che il consumo giornaliero di carne pro-capite emette 4,0 kg di CO2eq, con un contributo della care bovina pari al 30%, della carne suina pari al 9.6% e della carne avicola pari all’8%. Le emissioni relative ai SOA sono risultate essere pari al 60% di quelle totali e il loro riutilizzo ha permesso una riduzione di queste del 10%. Il secondo ed il terzo lavoro sono stati invece relativi al potenziale di riscaldamento globale (GWP) di latte bovino e Grana Padano DOP. Complessivamente sono stati valutate ventisette aziende zootecniche con bovine da latte, con latte destinato al formaggio Grana Padano DOP, e un caseificio, situato nella provincia di Piacenza. I dati primari sono stati raccolti utilizzando un questionario appositamente redatto. Questo ha incluso per le aziende agricole la richiesta di dati relativi alla composizione della mandria, la gestione dell'alimentazione, la produzione di latte e performance riproduttive, piani colturali e l'utilizzo delle risorse energetiche e dei materiali di lettime, mentre per il caseificio sono stati richiesti dati relativi all'utilizzo delle risorse energetiche e gli input richiesti dal processo di caseificazione. Nel secondo lavoro sono state valutate 10 aziende lattiere per valutare l'impronta di carbonio del latte (CF) e individuare le principali fonti di emissioni. Lo studio ha utilizzato un approccio dalla culla alla tomba considerando come unità funzionale un 1 kg di latte corretto per contenuto di grasso e proteine (FPCM). Il valore medio di CF di 1 kg di FPCM è risultato essere pari a 1,33 kg di CO2eq/kg FPCM con però un ampio range di variazione, da 1,02 a 1,62 kg di CO2eq/kg FPCM. Le emissioni dovute alle fermentazioni enteriche e alle fermentazioni da reflui rappresentano il 52% del totale, mentre le emissioni relative agli alimenti acquistati il 36%. L'autoproduzione e il consumo energetico rappresentano invece rispettivamente il 6% e il 6%. Nel terzo lavoro invece è stata presa in considerazione la produzione di Grana Padano DOP. In questo caso è stato utilizzato un approccio dalla culla al cancello del caseificio considerando come unità funzionali 1 kg di FPCM e 1 kg di Grana Padano DOP stagionato 9 mesi. Il latte destinato alla produzione del formaggio ha mostrato un valore medio di CF pari a 1,38 kg CO2eq/kg FPCM, con un valore minimo di 1,02 e uno massimo di 1,94 kg CO2eq/kg FPCM. Il valore medio di CF di 1 kg di formaggio Grana Padano DOP è stato invece pari a 9,99 kg di CO2eq, con un contributo della fase agricola pari al 94%. I risultati di questi lavori si sono mostrati in accordo con studi simili riportati in bibliografia e hanno inoltre permesso di evidenziare come gli allevamenti da latte mostrassero un maggior livello di sostenibilità ambientale ma con possibilità di miglioramento principalmente attraverso il miglioramento della gestione delle mandrie (prestazioni produttive e riproduttive). Il quarto lavoro ha riguardato invece lo sviluppo di proxy in grado di prevedere le emissioni di metano da singole bovine da latte. Questo focus è un punto caldo di ricerca, soprattutto perché di fondamentale importanza per individuare strategie di mitigazione efficaci per la riduzione delle emissioni di metano dovute a fermentazioni ruminali, gas ad effetto serra riconosciuto avere il maggior contributo sul totale delle emissioni. Le emissioni di metano dipendono principalmente dal quantitativo di concentrato assunto e dalla composizione generale della dieta, ma tuttavia nelle aziende agricole commerciali risulta difficile quantificare con precisione l’ingestione di alimenti. Lo studio ha quindi mirato a verificare la possibilità di utilizzare la tecnologia del vicino infrarosso (NIRS) utilizzando lo spettro di campioni di feci (NIRSf) e/o in combinazione con altri parametri fenotipici disponibili a livello aziendale per prevedere la produzione di metano (MP, g/giorno) dalle singole vacche da latte in lattazione. Il NIRSf da solo ha permesso una stima abbastanza buona della produzione di metano e le stime sono state migliorate in misura simile quando sono stati considerati il peso vivo o la produzione di latte tal quale o la produzione di latte corretta per il contenuto energetico, mentre la combinazione del NIRSf con più di un altro parametro ha migliorato le stime solo in misura molto limitata. Il metano può essere previsto utilizzando modelli che considerano l’ingestione di sostanza sezza, il peso vivo o la produzione di latte ma il limite principale è rappresentato dalla disponibilità dei dati a livello aziendale. La tecnica del vicino infrarosso applicata ai campioni fecali, in particolare se combinata con altri parametri fenotipici, può rappresentare una valida alternativa per misurazioni su larga scala in allevamenti da latte commerciali, quando l’ingestione di sostanza secca di solito non è disponibile, per la selezione genetica di vacche da latte a bassa emissione.
In the last three decades global demand of food, in particular animal proteins (meat, milk, and eggs), has increased according to the population growth, that is expected to go up to 9 billion by the 2050. These, in fact, represent an important source of energy, high-quality protein, micronutrients and vitamins. Therefore, this improvement could contribute to the lifespan increase and food demand. The latter forced the agricultural sector to a further intensification that affected also the cultivation of crops for animal feeding. Agricultural and livestock productions have a relevant environmental impact, and this topic is object of criticism and scientific investigation also to more accurately define its contribution and potential mitigation strategies, considering also that agricultural stage is the main contributor to the environmental impact of the food production chain. It is recognized, in fact, that agricultural sector directly contribute to the 21% of total global anthropogenic greenhouse gas emissions, mostly consisting of methane followed by nitrous oxide and carbon dioxide. These emissions are mainly associated with the livestock production, in particular with ruminants breeding that contributes directly to methane emissions due to ruminal and manure fermentation; the remaining part is composed by indirect emissions from deforestation, energy use and animal feed production. The scope of this thesis was the evaluation of environmental footprint in the livestock sector at different subject scale level. Italian meat supply chain, dairy farms, Grana Padano PDO cheese factory and single animals was investigated in order to quantify environmental footprint. In the first work, the Italian meat supply chain has been evaluated whit a mass flow analysis (MFA) approach and life cycle assessment (LCA) approach. Firstly, the quantification of meat had been made from slaughter to household consumption, starting form carcass weight to real meat consumed. At these levels, meat form cattle, pig, sheep and goat, equidae, and rabbit was taken in account. During the chain also meat losses and waste were quantified. In particular animal by-products (ABPs) were quantified for single species and categorized into heath level risk according to the Regulation (EC) 1069/2009. According to the category (Cat 1, Cat 2 or Cat3), assuming that all ABPs were destinated to rendering process, use and disposal of rendered products was identified. The MFA confirmed how Italy is a net importer of cattle and pork meat while it is self-sustaining for poultry meat. Mass flow analysis revealed that in 2013, 2.86 Mt of meat were consumed in Italy. It is equivalent to 131 g/day/pro-capita and to 47.91 kg/year/pro-capita of meat consumed. In percentage the total amount of consumed meat is represented by 46% of pig, 28% of poultry and 23% of cattle and 3% of other meat (rabbit, equidae, and sheep and goat). This approach quantified the ABPs produced at slaughtering level and food wastes at retail and consumer levels. Slaughter phase was the main source of waste, producing 0.80 Mt of ABPs, 48% of the total amount of waste originated in the meat supply chain. Results highlighted how the ABPs are already almost completely reused, compatibly with their health level risk, demonstrating the circularity of the system through the quantification of the avoided products and relative GHGs emissions. Concerning other food wastes, the results of the present evaluation could be considered only an estimate due to the lack of specific national coefficients. After quantification LCA was applied in order to evaluate environmental footprint, considering also avoided product due to the re-use of rendered ABPs. LCA results reveal that daily meat consumption pro-capita emits 4.0 kg CO2eq represented by 30% of cattle meat, 9.6% of pig meat and 8% of poultry meat. Emissions allocated to ABPs are the 60% and their re-use decrease the emissions about 10%. Second and third works focused the milk and PDO Grana Padano global warming potential (GWP). Overall, twenty-seven dairy farms, producing milk destinated to Grana Padano PDO cheese and one cheese factory, situated in the Piacenza province were evaluated. Primary data were collected by using a specific survey. This included for the farms the request of data regarding herd composition, feeding management, milk production, herd management and performace, crops cultivation and resource use, whereas for the cheese factory, the survey included energy resource use and input requested by cheese making process. In the second work, 10 dairy farms were evaluated in order to assess the milk Carbon Footprint (CF) and the main source of emissions. The system boundary was a cradle-to-farm-gate and functional unit is 1 kg of FPCM (Fat and Protein corrected milk). The CF of 1 kg of FPCM resulted equal to 1.33 kg CO2eq/kg FPCM with a wide range of variation from 1.02 to 1.62 kg CO2eq/kg FPCM. Emissions due to enteric fermentation and manure fermentation represented the 52% of the total, while acquired feed the 36%. Self-production and energetic consumption represented 6% and 6% respectively. In the third, Grana Padano PDO production was considered. The milk destinated to cheese processing showed an average value of CF equal to 1.38 kg CO2eq/kg FPCM, with a minimum value of 1.02 and a maximum one of 1.94 kg CO2eq/kg FPCM. Instead, the CF average value of 1 kg of PDO Grana Padano cheese was equal to 9.99 kg CO2eq, showing an agricultural stage contribution of 94%. Results of these works were in accord with similar studies reported in literature and had pointed out how dairy farms showed a greater level of environmental sustainability but with possibilities for improvement, mainly through herd management enhancement (productive and reproductive performances). Fourth work was about the development of proxies able to predict the methane emissions from individual cows. This focus is a hot research point in order to improve the mitigation strategies to reduce methane emissions because of the main GHG contributor. Methane emission is mainly driven by feed intake and diet composition, but it is difficult to measure intake in commercial farms. The study aimed to verify the possibility of using NIRS of faeces (NIRSf) alone and in combination with other phenotypic parameters available at a farm level to predict methane production (MP, g/d) from individual lactating dairy cows. NIRSf alone allowed a fairly good estimation of methane yield and the estimations were improved to a similar degree when BW, MY or ECM were considered, whereas combining NIRSf with more than one other parameters improved the estimations with a very little extent only. Methane can be predicted using models that consider the DMI, BW or MY but the main limitation is represented by the data availability. Near Infrared technique applied to faecal samples, in particular when combined with other phenotypic parameters, can represent a valid alternative for large-scale measurements in commercial dairy farms for genetic selection of low emitters dairy cows, when DMI measurement is usually not available.
Стилі APA, Harvard, Vancouver, ISO та ін.
38

Piñero, P. (Pablo). "The metabolism of socio-economic systems:combination of input-output analysis and material flow accounting for footprint-type indicators." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526224848.

Повний текст джерела
Анотація:
Abstract This thesis explored innovative ways to improve estimation of material footprint-type indicators in application of Input-Output (IO) analysis to Material Flow Accounting. The following six research questions were addressed: 1) What is the potential impact of sector aggregation in IO modelling of raw material flows? Modelling errors due to aggregation of industries with dissimilar material requirements and trade structures into a single sector in IO models when calculating the material footprint were empirically analysed relative to greenhouse gas emissions. Significant biases emerged for raw material flows, which suggests that care should be taken when aggregating extractive sectors in IO models. 2) Can bottom-up approaches, such as LCA (Life Cycle Assessment), improve estimation of the raw materials embodied in trade products? and 3) What are the implications of integration of country-specific information from high geographical coverage IO models into LCA approaches for calculation of raw material embodied in trade products? An approach for combining country-specific production blueprints with LCA based on regional averages was developed. This approach proved useful in refining estimates of upstream raw materials embodied in trade products, although care is needed during its application since new biases may arise. 4) Can further perspectives be gained with a new allocation method, the ‘value added-based material footprint’, which assigns supply chain-wide raw material extractions to each participating economic actor according to its added value generation, contributing to discussions on the distribution of mitigation costs? Certain countries and sectors were found to be more material-intensive with this new accounting approach than in other widely known allocation methods, e.g. consumer footprint. 5) Are there unequal exchanges between high-income economies and middle- and lower-income countries when measured in terms of raw material and value added flows? and 6) Could integration of local and global IO data provide useful insights to study presence/absence of unequal material exchange at sub-national level? A study of material flows at inter- and intra-national level demonstrated that a regional economy can play a twofold role, both as sink or source of raw materials and in value added, depending on its position in the global economic hierarchy
Tiivistelmä Tässä työssä tutkittiin innovatiivisia tapoja, joilla voitaisiin parantaa materiaalijalanjälki -tyyppisten indikaattoreiden käytettävyyttä panos-tuotos (Input-Output, IO) -analyysissa, kun niitä sovelletaan Materiaalivirta-analyysi (Material Flow Accounting, MFA) -metodiin. Seuraaviin tutkimuskysymyksiin haettiin vastauksia: 1) Mikä on sektorien yhdistämisen potentiaalinen vaikutus raaka-ainevirtojen IO-mallintamisessa ja miten poikkeamia voidaan estää? Tämän puitteissa tarkasteltiin mallinnusvirheitä, jotka johtuvat erilaisten toimialojen yhdistämisistä yhdeksi sektoriksi. 2) Voivatko alhaalta ylöspäin suuntautuvat lähestymistavat, kuten elinkaariarviointi parantaa tuotteisiin sisältyvien raaka-ainevirtojen arviointia? ja 3) Mitä vaikutuksia on laajan maantieteellisen kattavuuden IO-malleihin sisältyvien maakohtaisten tietojen yhdistämisestä LCA-pohjaisiin lähestymistapoihin, kun tavoitteena on laskea tuotteisiin sisältyviä raaka-ainemääriä? Tämän tutkimista varten kehitettiin lähestymistapa, joka yhdisti maakohtaiset tuotantosuunnitelmat ja elinkaariarvioinnin. Tämä lähestymistapa osoittautui hyödylliseksi tarkentamalla arvioita tuotteissa olevista raaka-aineista, vaikkakin sen soveltaminen edellyttää varovaisuutta, koska uusia vääristymiä voi syntyä. 4) Voidaanko uusia näkökulmia löytää uudella arvonlisäykseen perustuvalla allokointimenetelmällä, joka jakaa raaka-aineen louhinnan kullekin toimintaketjun osallistuvalle taloudelliselle toimijalle lisäarvon tuotannon mukaan? Tämän uuden kirjanpitomenetelmän mukaan jotkut maat ja alat ovat materiaali-intensiivisempiä kuin niitä on pidetty kulutuksen jalanjälkiallokointimenetelmien perusteella. 5) Onko korkean tulotason talouksien ja keskitasoiselle ja alhaiselle tulotasolle asettuvien maiden välillä epätasaisia vaihtoja, kun raaka-ainekulutusta ja arvonlisäystä mitataan? ja 6) Voisiko paikallisten ja globaalien IO-tietojen integrointi antaa hyödyllisiä näkökulmia tutkimukseen, joka tarkastelee epätasaisen aineenvaihdon esiintymistä tai puuttumista alueellisella tasolla? Materiaalivirtojen tutkiminen kansainvälisellä ja kansallisella tasolla, jossa yhdistettiin IO-tietokannat erilaisella maantieteellisellä resoluutiolla osoitti, että alueellisella taloudella voi olla kaksoisrooli sekä raaka-aineiden että arvonlisäyksen lähteenä tai nieluna riippuen sen asemasta globaalissa taloushierarkiassa
Стилі APA, Harvard, Vancouver, ISO та ін.
39

Bergquist, Daniel A. "Colonised Coasts : Aquaculture and Emergy Flows in the World System: Cases from Sri Lanka and the Philippines." Doctoral thesis, Uppsala : Department of Social and Economic Geography, Uppsala University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8412.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
40

Lin, Shiou-Wei, and 林修緯. "Environmental Flow Assessment Considering Flow Regime-The Case Study of Dahan River." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/yws8m6.

Повний текст джерела
Анотація:
碩士
國立交通大學
土木工程系所
104
Water is the necessary resource for living creatures. Human beings usually build hydraulic structures to satisfy human’s water needs. Excessive water usage impacts the natural environment of rivers. The key factor to protect the river ecology is the reserved discharge in the river. Traditionally, this reserved discharge is determined for single objective or is determined as a minimal discharge rate which did not consider the complexity of the river ecology. In addition to ecology, the reserved discharge also affects the water usage for human beings. Therefore, the influence analysis for different scenarios is necessary for balancing both side of water needs. The main purpose of this study is developing a systematic way to propose alternative scenarios for trade off analysis among river ecology, human activities, and natural environment. For these alternative scenarios, this study not only considers water quantity, water quality, and duration time, but also evaluates the corresponding impact related to human water usage and ecological environment.   This study applies the proposed method to Dahan River. Current Dahan River is under the situation of excessive use. The ecological environment at the downstream river is seriously damaged. This study collects the ecology, hydrology, and geology data to assist the determination of the environmental discharge management targets. Each management target is quantified using different evaluation methods. Eight alternative scenarios are proposed based on the combination of these quantified indices. These alternative scenarios are then compared with the current system, as defined the based case or Case 0. The Shortage Index (SI) and the integrated hydrology changes are used to evaluate the impact of human water usage and ecological environment.   The study found that the lowest impact scenarios for human water usage and ecological environment are Case 3 and Case 4 respectively. In Case 3, with comparison of Case 0 for Taoyuan area, the SI value increases 0.136 which indicates a slightly negative influence for human water usage. For river sections 1, 2, and 4, the integrated hydrology is reduced by 1.7%, 1%, and 0.1% respectively. This reduction refers slightly improvement for these river sections. In Case 4, with comparison of Case 0 for Taoyuan area, the SI value increases 13.3 which indicates a severely negative influence for human water usage due to high reserved discharge rate. On the other hand, the river ecology is improved according to the integrated hydrology is reduced by 10.3%, 13.8%, 10.5% and 10.4% for river sections 1 through 4 respectively.   In this study, the environmental discharge is represented by river status. In addition, multiple quantitative management objectives are considered to evaluate the impacts for human beings and ecology using alternative scenarios. The results can be a decision reference for government and interested parties.
Стилі APA, Harvard, Vancouver, ISO та ін.
41

Chang, Chi-Hui, and 張琪惠. "Material Flow Analysis and Environmental Impact Assessment of Lead in Taiwan." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/02763352593584318348.

Повний текст джерела
Анотація:
碩士
國立臺灣大學
環境工程學研究所
98
Lead is one of the most widely used heavy metals in Taiwan, but it’s toxic. In this study, material flow analysis (MFA) is used to quantify the mass flow of lead in Taiwan to understand the use of lead and find out the hot spots of lead emission. With the combination of MFA and life cycle impact assessment (LCIA), the emission of lead is associated with impact of human health and freshwater ecotoxicity as the basis for the environmental management of lead. There is no lead mineral production in Taiwan; all lead resource rely on imports and there are about 148,518 tons of lead imported in 2008. The main lead products are lead acid battery (43.8%), lead metal and alloy product (22.5%) and electronic components (8.1%). The highest lead demand industries are other metal, electrical equipment and chemical material. For the production of lead metal, lead alloy and lead compound, the demand of lead material is quite high in other metal industry and chemical material industry. And the lead material demand of electrical equipments is for the production of lead acid battery and the addictive in PVC cable as stabilizer. Since lead acid battery is the main product flow in Taiwan, the lead demand of electrical equipment is higher than that of other industries. Lead emission includes air, effluent and solid waste. There are about 3,396 tons of lead emitted as gas, 16 tons lead emitted as effluent and 30,042 tons lead disposal as solid waste. And lead recycled amount is about 111,397 tons. Combustion of coal, incineration of lead-containing waste and the use of lead as solder are main air pollution sources. Waste water from electronic components, metal products, wholesale and retail, chemical materials and electrical equipment industries are the major lead effluent. And most lead solid waste is disposal by electronic components industry and pollution remediation industry. USEtox is used to evaluate the characteristic factor (CF) of human toxic impact and freshwater ecotoxic impact. The CF of emission to continental agriculture soil is highest for human toxic impact and CF of emission to freshwater is highest for ecotoxic impact. However, the lead emission variation among different forms is high. Thus, air emission results in highest toxic impact. To minimize the toxic impact caused by lead in Taiwan, the reduction of lead air emission is necessary.
Стилі APA, Harvard, Vancouver, ISO та ін.
42

SINGH, ANURAG. "ENVIRONMENTAL FLOW ASSESSMENT FOR ECOSYSTEM HEALTH IN A REACH OF BAITARANI RIVER." Thesis, 2018. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16376.

Повний текст джерела
Анотація:
Rivers have always been vital to mankind as well as for other living beings infact, most civilizations started from the bank of Rivers. Since Rivers have been a source of food and home for variety of aquatic plants and animals and sustains an ecosystem, the alteration of the water flow is one of the most stressful factors influencing the aquatic and riverine ecosystem. Salubrious ecosystems help preserving the food, maintain the cycle of symbiotic relationship and keeps water quality healthy, therefore the condition of aquatic ecosystem is a measure for environment which depends on the flow in the stream. This essential flow is termed as Environmental Flow. Rivers need Environmental Flow to maintain the ecology of the systems and also sometimes rivers have to face water related challenges including increasing issue of the water scarcity and distribution for water among different sectors and states are being faced presently at global level. The present study aims to estimate the Environmental Flow of Baitarani River upto Anandapur, Odisha from its origin and analysis of eco-hydro relationships in time by environmental flow assessment. WMS, HMS, DSSvue and EFM software were used for assessing the Environmental Flow employing the DEM (Digital Elevation Model), precipitation, soil, Land use land cover (LULC), discharge, gauge and ecosystem data for the aquatic species in the present study. The environmental indicators employed for the research are Small Fishes, Maggar, Benthic Macro-Invertebrate Biodiversity, Wetland, Catla-Catla, Rohu, Hilsa and their corresponding assessed E-flow are 148, 6, 7, 122, 267, 254 and 272 cumecs respectively for observed flow of 17 years viz. 2000 to 2016. Through confiscate such as dams, barrages and weirs which are constructed for irrigation, drinking water, hydro-project and for other industrial demand. This does not only make restriction on the flow of water but also degrade the water quality. An attempt has also been made to estimate the E-flow which could only be provided upto certain values in case of climate change and future development flow regime for the above mentioned species and their corresponding values are 129, 5, 6, 106, 232, 221, 236 and 52, 2, 3, 43, 93, 89, 95 cumecs respectively.
Стилі APA, Harvard, Vancouver, ISO та ін.
43

Chuang, Chi-Yang, and 莊志揚. "Assessment of the Status about Home Kitchens - Environmental Airflow Interference and Flow Field Correlation." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/hx6r85.

Повний текст джерела
Анотація:
碩士
國立臺灣大學
職業醫學與工業衛生研究所
107
We conducted a survey of the home kitchen in Taipei area and discovered the inhalation distance, curved hood and crosswind in the current home kitchen. We divided the kitchen into the three types: independent kitchen, peninsula kitchen and open kitchen respectively. We found the problems of range hood, distance, and curved hood at home and had already affected the exhaust effect of the range hood. In the study, we studied the flow, velocity, temperature, and concentration fields of the three kitchens in a crosswind. The results from the study show that all the three types of kitchens have problems with the leakage of cooking oil fume (COF), and we found the concentration and temperature diffusion in the environment where was affected by crosswind are more extensive than non-crosswind environment. In the open kitchen with cross draft, the cooking fumes will escape the effective capture area of the range hood in ten seconds. After simulating different distance between the air supply and the range hood, 1.8 m, 3 m and 3.5 m respectively. We found that the kitchen with a distance of 3 m from the air inlet and the range hood has better flow field characteristics. The other two leak due to the vortex generated above the hood. Based on the distance between air supply and the range hood is 3 m, we simulated three different flow rate, 10 CMM, 15 CMM, 20 CMM respectively. When the flow rate was greater than 15 CMM, the COF under the range hood was captured. Compared to the flow rate in 10 CMM, the effect capture velocity near the stove was not enough to exhust the cooking fumes.
Стилі APA, Harvard, Vancouver, ISO та ін.
44

Kwonpongsagoon, Suphaphat Civil &amp Environmental Engineering Faculty of Engineering UNSW. "Integration of substance flow analysis, transport and fate of materials in the environment, and environmental risk assessment for provision of information for regional environmental management: cadmium as a case study in Australia." 2006. http://handle.unsw.edu.au/1959.4/40655.

Повний текст джерела
Анотація:
Extraction, production, utilization and disposal of material resources have been undertaken continuously for much of human histories. Unavoidably, all of these activities have disturbed our environment, and subsequently have been harmful to humans and ecosystems in this and future generations. Due to time lag associated with both environment impact and the effects of measures taken to reduce this impact, existing approaches (i.e. monitoring and reacting) do not give sufficiently rapid feedback for effective environmental management. With regard to the complexity and concern related to environment-health chain effects, there is currently no environmental tool or approach that can provide comprehensive information and indicators covering all major environment and health themes, to enable decision makers to make informed judgements about regional policies and plans, relating to the sustainable use and disposal of material resources. Consequently, there is a need for developing a new approach by taking account of a multidisciplinary concept used in this thesis. Substance Flow Analysis (SFA) has been mainly applied in order to provide input information for Health Risk Assessment (HRA). The SFA approach provides the quantity of the substance that is transported (flows) and stored in the system (stock), and of which sub-system, flow, and process is the greatest concern. The HRA approach provides estimates of human health risk associated with site, activity and facility. An environmental fate and transport model is another key knowledge area incorporated into the HRA process. An integrating method of SFA, environmental fate and transport, and HRA is developed and illustrated by a case study of cadmium in Australia. This thesis shows that this new integration of existing stand-alone methods can provide holistic information and useful indicators covering all significant economic activities, environment, flows, and health risk assessment for selected substances. This enables better decision making on the use and disposal of substances at a range of levels in the economy, from corporations to regions and nations.
Стилі APA, Harvard, Vancouver, ISO та ін.
45

Szemis, Joanna Margaret. "An adaptive multi-objective framework for the scheduling of environmental flow management alternatives using ant colony optimization." Thesis, 2014. http://hdl.handle.net/2440/99032.

Повний текст джерела
Анотація:
Rivers and their adjacent wetlands and floodplains worldwide have been altered or have vanished as a result of river regulation and development (such as dams, locks and weirs), as well as water over-allocation. In recent years, environmental flow management has been suggested as a means to mitigate these negative impacts. One approach in order to do this is through the scheduling of environmental flow management alternatives (EFMAs), such as reservoir releases and the operation of wetland regulators. However, this is not an easy task for the following reasons: (i) there are generally many wetlands and floodplains in any particular river system, all containing a wide range of biota that have different flow requirements; (ii) there is generally limited water allocated for environmental purposes, since there are multiple users (e.g. irrigation, domestic), all competing for the same water source; (iii) the schedules are generally developed over multiple years; and (iv) there are multiple competing objectives and constraints that need to be considered. This problem therefore lends itself to be formulated as an optimization problem, where the aim is to maximise the ecological integrity of the system, while also considering humans needs and the constraints of the system. In this thesis, a generic adaptive multi-objective optimization framework for determining the optimal schedule of EFMAs for rivers and their associated wetlands and floodplains is developed and tested. In order to achieve this, ant colony optimization algorithms are selected, since they can take into account the conditional dependencies and sequential nature of the scheduling problem explicitly. This is possible, as the solution space can be represented by a graph structure that can be adjusted dynamically based on the choices made at previous points in the decision graph, thereby reducing the size of the decision space and increasing the proportion of feasible solutions. This is not possible when most other metaheuristics are used. In addition to this, the framework is adaptive and able to incorporate forecasts of environmental water allocation, such that the environmental water can be used most efficiently in order to maximize ecological response. The major research contributions are presented in three journal publications. Firstly, the initial single-objective formulation of the optimisation framework, which incorporates the temporal dependencies associated with the scheduling of EFMAs is presented and validated using a hypothetical case study. The framework is then extended to incorporate multiple objectives and applied to a river section in the South Australian River Murray, so that the trade-off between the ecological response and environmental water allocation can be examined. Finally the framework is further extended to incorporate adaptive features by using forecasts of environmental water allocation in the development of EFMA schedules, as well as an additional objective which aims to minimise the number of differences of EFMA schedules developed at subsequent time steps. Thus the framework provides valuable insight to managers into the EFMA scheduling problem, as it can be applied to investigate a wide variety of problems, such as investigating the likely ecological benefit gained from an increase in environmental allocation, the impact of system constraints on ecological response and the potential advantages of investment in additional infrastructure.
Thesis (Ph.D.) -- University of Adelaide, School of Civil, Environmental and Mining Engineering, 2014
Стилі APA, Harvard, Vancouver, ISO та ін.
46

Karanovic, Nikola. "Environmental analysis of construction and demolition waste in urban areas using LCA tools: case study of Portugal (Aveiro)." Doctoral thesis, 2021. http://hdl.handle.net/10773/32259.

Повний текст джерела
Анотація:
Construction and demolition (C&D) waste derives from activities such as the construction, renovation and demolition of infrastructures. The goal of this research is to improve understanding of the impacts of C&D waste management and to promote better C&D waste management planning. This thesis descrbies environmental analysis of C&D waste management in Aveiro (Portugal) and application of materials flow analysis (MFA) by analysing two scenarios (MFA scenario I, which describes current situation of C&D waste management system, and MFA scenario II, which follows the EU waste framework directive that encourage the reuse of construction materials and products. Analysing C&D waste fractions through the processes of recovery (R1- R13) and disposal, by applying impact methods ReCiPe (midpoint) and IPCC 2013 (Climate Change GWP100a), it is concluded that parameter “Waste C&D inert fraction” has the highest contribution in terms of impacts to the environment in all the analysed impact categories. Cadmium, chromium, copper, mercury, lead and zinc are substances of environmental concern and those elements are analysed throughout C&D system of Aveiro by applying substance flow analysis approach (MFA/SFA). During the processing of C&D waste, analysed heavy metals dissipate to the air, soil and water. In the analysed processes, zinc has highest constribution (in the context of dissipation) to the air, soil and water. Theoretical approach for the relationship of MFA/SFA and dissipation of analysed heavy metals is suggested. The obtained results can be used to define future strategies for C&D waste management, while the developed method can be applied for development and evaluation of new scenarios and different municipalities, with the aim of improving C&D waste management systems at all levels.
O resíduo de construção e demolição (RCD) provém da atividade de construção que inclui as obras de construção, ampliação, alteração, renovação e demolição de edificações. O objetivo do presente estudo é dar um contributo no sentido de melhorar a compreensão dos impactes ambientais da gestão RCD e assim promover a sua boa gestão. Nesse sentido é realizada a análise ambiental da gestão de RCD, tendo por base o caso de estudo da cidade de Aveiro - Portugal, e aplicando ferramentas de avaliação ambiental. A análise de fluxo de materiais (MFA) é aplicada a dois cenários (cenário MFA I, que descreve a situação atual do sistema de gestão de RCD, e cenário MFA II, que segue as orientações da Comunidade Europeia). Foi avaliado o impacte ambiental associado à gestão das diferentes frações de RCD, através dos processos de valorização (R1-R13) e de eliminação, aplicando os métodos de avaliação de impacte ambiental de ciclo de vida ReCiPe (midpoint) e IPCC 2013 (Alterações Climáticas, GWP100a), verificandose que a fração inerte de RCD tem a maior contribuição em todas as categorias de impacte analisadas. Os elementos cádmio, crómio, cobre, mercúrio, chumbo e zinco, são substâncias de preocupação ambiental que foram analisados nas operações de gestão de RCD, aplicando a metodologia de análise de fluxo de substâncias (MFA/SFA). Durante o processamento dos RCD, os metais pesados analisados são dissipados no ar, no solo e na água. Nos processos analisados, o zinco é o elemento que maior dissipação apresenta para o ar, solo e água. É sugerida uma abordagem teórica para a relação de MFA/SFA e de dissipação dos metais pesados analisados. Os resultados obtidos no presente estudo, podem ser utilizados para definir estratégias futuras para a gestão de RCD, a abordagem desenvolvida pode ser aplicada para o desenvolvimento e avaliação de novos cenários e para diferentes municípios, com o objetivo de melhorar os sistemas de gestão de RCD, a todos os níveis.
Programa Doutoral em Ciências e Engenharia do Ambiente
Стилі APA, Harvard, Vancouver, ISO та ін.
47

Feng, Kuo-Lun, and 馮國倫. "Integrating Material Flow Analysis with Life Cycle Assessment to Analyze Environmental Impacts of Water-Energy-Food Nexus System in Taiwan." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/uqvj5j.

Повний текст джерела
Анотація:
碩士
國立臺灣大學
環境工程學研究所
107
As water, energy and food resource demands and interdependencies continue to increase, the WEF resource management strategies of a single problem-oriented thinking mode have been gradually replaced bythe nexus thinking mode attaching importance to the relationship between different resources. By this way, it is considered to avoid problem transfer and bring co-benefits. However, although the WEF Nexus concept has been widely accepted, most of the current literature on WEF Nexus only provides guidelines for resource management. There is no standard method for decision making. On account of complex relationship between WEF resources, if quantitative assessment tools are used to provide numerical result for the issue, decision makers can have better decision-making basis. This study intends to use quantitative assessment tools to analyze the correlation of environmental impacts between water, energy and food resources systems on large scales from the perspective of urban metabolism. This study integrates material flow analysis (MFA) with life cycle assessment (LCA) as the tool. MFA is used to clarify the process of water, energy and food from production to consumption to understand the role of various socio-economic sectors and WEF sectors. LCA is used to quantify environmental impact as an evaluation indicator. In the overall impact calculation, the two calculation methods of the WEF subsystem and the total system are distinguished. At the same time, in order to observe the influence of resource nexus relationship on the result, the nexus coefficient matrix established on the basis of the current scenario material flow analysis is used to locate the most influential process in the nexus system regarding environmental impact by a sensitivity analysis. Then, based on the current government''s management strategy for the future WEF resources, the nexus coefficient is adjusted as the future scenarios, and the multi-sector strategic scenario are compared with the single-sector strategic scenario. From the results of sensitivity analysis and scenarios analysis, the influences of changes in nexus relationships on the environment impactd of the different system is evaluated under the same resource requirements. By the current scenario MFA, it is found that water treatment, oil refining, steam and electricity symbiosis, thermoelectric power plant, irrigation, livestock, and aquaculture processes require WEF resources which are in the boundary. Among them, the water supply plant, the public power plant, the steam and electricity co-generation plant, and the refinery have bidirectional relationship with each other''s final products as needed, so the environmental impact is affected by each other. The midpoint indicators displayed ReCiPe methodology is applied to evaluate the environmental impact. From the current scenario environmental impact result of the total system, the public power contributes the most on seven impact categories such as climate change; the oil product contributes the most on fossil depletion ozone depletion, ionising radiation; the tap water contributes the most on metal depletion; the livestock products contributes the most on terrestrial ecotoxicity. Among them, the public power is the most demanded by the industrial sector; the tap water and the livestock products is the most demanded by residential sector; the oil product is the most demanded by the export. From the current scenario environmental impact result of the subsystem, excluding human toxicity, marine ecotoxicity, water depletion, and metal depletion, the energy system has a main contribution on the rest of the impact in the water system. By contrast, the main contribution of energy system impacts comes from itself, and only on water depletion, the water system is influential. When it come to the food system, ozone depletion, ionising radiation, and fossil depletion energy systems is influential. The sensitivity of the 16 nexus coefficients to the current scenario impact results is analyzed. It is found that the coefficient of water leakage is the first to influence the total, water and energy systems on climate change, water depletion and metal depletion. The future scenarios analysis shows that the water-energy bi-strategy scenario has more impact than the single-strategy scenario on terrestrial ecotoxicity and freshwater ecotoxicity; and more improvement on water depletion and metal depletion for total system. In contrast with total system, for water system, on seven impact categories such as climate change, the impact of the water resources development plan has slowed down under the non-nuclear home power generation structure, but it is still higher than the basic scenario. It is mainly necessary to improve the water energy nexus coefficient by itself. In conclusion, this study uses material flow analysis combined with life cycle assessment methods to convert a variety of products from resource quantities to environmental impact indicators as a unified comparison standard, and assess the environment impact relationship between WEF systems under different scenarios of water-energy technologies. Through this study, we improve the understanding of the metabolism of WEF nexus systems, with a view to promoting cross-sectoral synergy benefit.
Стилі APA, Harvard, Vancouver, ISO та ін.
48

Marx, Conrad. "Prediction of antibiotic mass flows in urban catchments and their environmental prioritization." Doctoral thesis, 2015. https://tud.qucosa.de/id/qucosa%3A28838.

Повний текст джерела
Анотація:
Urban emissions of antibiotics into the environment have the potential to adversely affect terrestrial and aquatic organisms. Developed standardized test methods allow the quantification of the resulting ecotoxicological risk, which strongly relies on a comprehensive situation analysis by predicting or measuring a representative antibiotic concentration of interest. Predicting the input loads of antibiotics to wastewater treatment plants using secondary input data (e.g. prescriptions) is a reasonable method if no analytical data is available. The absence of such data poses the question of an aquired reasonable sample quantity to capture local seasonal differences in prescriptions as well as flow conditions within the catchment area. Both, the theoretical and measurement based determination of environmental concentrations have been scarcely verified in practice. Hence, high resolution prescription data in combination with an extensive monitoring campaign at the wastewater treatment plant Dresden-Kaditz (WWTP) were used as a basis to evaluate the reliability of predicting and measuring urban antibiotic emissions. As expected, the recovery of antibiotic input loads strongly varies among substances. The group of macrolides as well as sulfamethoxazole and trimethoprim were almost fully recovered whereas nearly all substances of the beta-lactam family exhibit high elimination rates during the wastewater transport in the sewer system. Yet other antibiotics (e.g. fluoroquinolones) show distinct fluctuations through the year, which was not obvious from relatively constant prescriptions. The latter substances are an example that available data are not per se sufficient to predict the actual release into the environment which, in certain cases, emphasizes the necessity of adequate measuring campaings. The extensive data pool of this study was hence used to calculate the necessary number of samples to determine a representative annual mean load to the WWTP. Based on the applied approach, a minimum number of 20 to 40 samples per year is proposed to reasonably estimate a representative annual input load of antibiotics and other micropollutants. Regarding the WWTP, the mass flow analysis revealed that macrolides, clindamycin/ clindamycin-sulfoxide and trimethoprim were mainly released with the effluent, while penicillins, cephalosporins as well as sulfamethoxazole were partly degraded in the studied WWTP. Levofloxacin and ciprofloxacin are the only antibiotics under investigation with a significant mass fraction bound to primary, excess and digested sludge. In this context, the sludge concentrations are considered to be highly inconsistent which leads to questionable results. It remains unclear whether the inconsistencies are due to insufficiencies in sampling and/or analytical determination or if the fluctuations can be considered reasonable for digesters. Subsequently, verified antibiotic loads were evaluated regarding their ecotoxicological effects in the aquatic environment. Two approaches were applied (1) to address the ecological impact on individual trophic levels algae, daphnia and fish, and (2) to assess the possible synergistic potential of antibiotic combinations. Ciprofloxacin, levofloxacin and the group of cephalosporins showed to significantly affect the aquatic environment. They either have the highest impact on (one of) the lowest trophic level(s) or disproportionately increase the ecotoxicological risk due to their synergistic characteristics. In this regard, the deficiencies regarding the input prediction of these antibiotics is of particular concern. The underestimation of such critical mass flow conditions weakens the approach of assessing environmental risks on the basis of secondary data like prescriptions. Hence, efforts must be made to further develop the projection model by improving the quality of secondary data, identifying additional emitters and understanding possible retention and degradation dynamics of antibiotics within the sewer system.:Abstract 2 Danksagung 1 Table of Contents 1 Chapter 1 – Introduction 1 Scope 1 Goals and structure 3 Approach and Methods 5 Chapter 2 – Representative input load of antibiotics to WWTPs: Predictive accuracy and determination of a required sampling quantity 11 Introduction 14 Materials and Methods 16 Results and discussion 24 Conclusion 38 References 39 Chapter 3 – Mass flow of antibiotics in a wastewater treatment plant focusing on removal variations due to operational parameters 41 Introduction 45 Materials and Methods 47 Results and discussion 52 Conclusions 65 References 66 Chapter 4 – Species-related risk assessment of antibiotics using the probability distribution of long-term toxicity data as weighting function – a case study 71 Introduction 74 Materials and Methods 75 Results and discussion 86 Conclusions and summary 93 References 95 Chapter 5 – Environmental risk assessment of antibiotics including synergistic and antagonistic combination effects 99 Materials and Methods 104 Results 113 Discussion 120 Conclusions and summary . 125 References 126 Chapter 6 – Results and conclusions 129 Individual results 131 Aggregation of results 133 Final conclusions 134 References 139 Annex 1 – Supplementary material Chapter 2 141 Annex 2 – Supplementary material Chapter 3 147 Annex 3 – Supplementary material Chapter 4 159 Annex 4 – Supplementary material Chapter 5 177
In der Humanmedizin eingesetzte Antibiotika werden im menschlichen Körper nicht vollständig metabolisiert und gelangen über die Ausscheidungen in das kommunale Abwasser. In der Kläranlage erfolgt nur eine unvollständige Elimination dieser Stoffe, so dass der Kläranlagenablauf einen Hot Spot für Antibiotikaemissionen in die Umwelt darstellt. Das induzierte ökotoxikologische Risiko kann anhand standardisierter Testverfahren und allgemein anerkannter Bewertungsansätze für Einzelsubstanzen abgeschätzt werden. Erfolgt jedoch die Betrachtung von Antibiotikagemischen, wie es für den gereinigten Ablauf einer Kläranlage sinnvoll ist, sind aufgrund zumeist unspezifischer Wirkmechanismen und dem Mangel an repräsentativen Daten eine Reihe von Vereinfachungen und Annahmen zu treffen. Es besteht in der Folge die Gefahr einer Unterschätzung des durch Substanzgemische hervorgerufenen ökotoxikologischen Risikos. Eine vielversprechende Möglichkeit den Entscheidungsprozess über mögliche Vermeidungs- und Eliminationsmaßnahmen zu unterstützen besteht in der Priorisierung von Antibiotika entsprechend ihres Effektpotentials. Hierbei sind Substanzen zu identifizieren, die den größten Einfluss auf die Nahrungskette im Gewässer bzw. das höchste (negative) Synergiepotential mit anderen Substanzen aufweisen. Die Verringerung dieser Substanzen führt zu einer hohen ökologischen Effektivität und Effizienz der eingesetzten Mittel. Wie im Fall des klassischen Bewertungsansatzes, ist auch für den Priorisierungsansatz eine umfängliche und zuverlässige Situationsanalyse die Grundvoraussetzung für verwertbare Ergebnisse. Die Situationsanalyse beruht auf der analytischen Bestimmung bzw. der Abschätzung von emittierten Antibiotikafrachten zur Berechnung von repräsentativen Umweltkonzentrationen. Analytisch ermittelte Umweltkonzentrationen vieler Antibiotika weisen aufgrund saisonaler Verschreibungsmuster eine hohe zeitliche und räumliche Variabilität auf. Die für eine adäquate Erfassung der Situation notwendigen Messkampagnen sind kostenintensiv, wobei die tatsächlich notwendige Häufigkeit der Probenahme von zumeist nicht hinreichend bekannten substanzspezifischen Informationen, wie der chemischen Stabilität im Rohabwasser und der saisonal beeinflussten Applikation, abhängt. Alternativ können Antibiotikaeinträge in die Kanalisation anhand von Verschreibungsdaten abgeschätzt und mit Hilfe von Stoffflussanalysen (SFA) zur ökotoxikologischen Bewertung herangezogen werden. Eine vom Umfang befriedigende, direkte Gegenüberstellung von prognostizierten und analytisch ermittelten Frachten ist bisher jedoch nicht erfolgt, so dass die Verifizierung dieses Ansatzes noch aussteht. Für den Fall einer bestehenden Verschreibungspflicht für Antibiotika besitzen Verschreibungsdaten eine vergleichsweise hohe zeitliche und räumliche Informationsgüte. In Verbindung mit einer an diese Datenqualität angepassten Messkampagne, ergibt sich die Möglichkeit einer detaillierten SFA mit substanzspezifischer Bewertung der Eignung des Prognoseansatzes. Die am Beispiel der Stadt Dresden durchgeführte Bewertung des Prognoseansatzes fußt auf einer 15-monatigen Messkampagne und den für das Einzugsgebiet der Zentralkläranlage Dresden-Kaditz verfügbaren Verschreibungsdaten der AOK PLUS. Erwartungsgemäß ergibt der Abgleich von erwarteten und analytisch ermittelten Frachten eine starke Variation der für den Zulauf der Kläranlage ermittelten Wiederfindungsdaten verschiedener Substanzen. Die analytisch ermittelten Frachten von Sulfamethoxazol, Trimethoprim sowie der Gruppe der Makrolid-Antibiotika entsprechen nahezu den prognostizierten Mengen. Die Beta-Laktam-Antibiotika unterliegen bereits während des Abwassertransports einer umfänglichen, zumeist biologisch bedingten, Elimination, was zu hohen Unterbefunden im Zulauf der Kläranlage führt. Andere Substanzen hingegen (z.B. Fluorchinolone) weisen messtechnisch eine signifikante Jahresdynamik auf, die aufgrund der weitgehend konstanten Verschreibung in dieser Ausprägung nicht zu erwarten ist. Die Auswertung zuletzt genannter Substanzen zeigt deutlich, dass die Nutzung von Verschreibungsdaten nicht per se ausreicht, um die Emission von Antibiotika (und anderer Pharmazeutika) sowie die sich daraus ergebenden Umweltkonzentrationen mit ausreichender Sicherheit prognostizieren zu können. Für eine nachgelagerte ökotoxikologische Bewertung ist in diesen Fällen die Durchführung von Messungen unumgänglich. Zur effizienten Planung derartiger Kampagnen wurde der umfassende Datenpool dieser Studie hinsichtlich der erforderlichen Probenanzahl zur Bestimmung einer repräsentativen mittleren Jahresfracht ausgewertet. Es ergibt sich ein Minimum von 20 bis 40 homogen über das Jahr verteilten Proben, um die jährlich in die Kläranlage eingetragene Fracht an Antibiotika bzw. anderer Mikroschadstoffe mit ausreichender Sicherheit abschätzen zu können. Im Rahmen der SFA in der Kläranlage Dresden-Kaditz wird deutlich, dass Makrolide, Clindamycin und dessen Humanmetabolit Clindamycin-Sulfoxid sowie Trimethoprim in der nahezu keiner Elimination unterliegen, wohingegen Penizilline, Cefalosporine und auch Sulfamethoxazol teilweise bis vollständig abgebaut werden. Mit Levofloxacin und Ciprofloxacin handelt es sich um die einzigen untersuchten Antibiotika, welche zu einem signifikanten Massenanteil an Primär-, Überschuss- und Faulschlamm gebunden vorgefunden werden. Aufgrund der hohen Relevanz dieses Eliminationspfades für die zuvor genannten Antibiotika bedarf die Beobachtung von z. T. widersprüchlichen Schwankungen einer kritischen Betrachtung der Ergebnisse. Es ist nicht abschließend geklärt, ob die beobachteten Fluktuationen auf eine unzureichende Qualität der Probenahme und/oder der Analytik zurückzuführen sind oder sich die Schwankungen in einem für Faulbehälter tolerierbaren Bereich befinden. Im Anschluss an die verifizierten Antibiotikaemissionen erfolgte die Priorisierung der betrachteten Antibiotika nach ihrem ökotoxikologischen Effektpotential. Zum einen wurde der ökologische Einfluss auf verschiedene, die Nahrungskette bildende trophische Ebenen (Alge, Daphnie, Fisch) untersucht. In Anlehnung an die humanmedizinische Kombinationstherapie erfolgte im zweiten Ansatz die Beurteilung der Antibiotika hinsichtlich ihres möglichen Potentials zur Verstärkung von negativen Effekten durch das gleichzeitige Auftreten mit anderen Substanzen. Für Ciprofloxacin, Levofloxacin und die Gruppen der Makrolide und Cefalosporine konnten signifikante Beeinträchtigungen der aquatischen Umwelt nachgewiesen werden. Diese Stoffe und Stoffgruppen führten im Rahmen der untersuchten Substanzen entweder zur höchsten Schadwirkung gegenüber der niedrigsten trophischen Ebene oder besitzen das höchste Synergiepotential in Kombination mit anderen Substanzen. Die Auswertung der SFA bestätigt die grundsätzliche Eignung der Verschreibungsdaten sowie des entwickelten Prognosemodells zur Vorhersage von Antibiotikaemissionen im urbanen Raum. Die Stoffflussanalyse stellt somit ein strategisches, im Vergleich zur Messung kostengünstiges Instrument zur Identifikation von Hot Spots der Antibiotikaemission dar und erleichtert die Entscheidungsfindung für monetär aufwendige Reduktionsmaßnahmen am Ort der Entstehung oder in der Kläranlage (z.B. 4. Reinigungsstufe). Die Vorgehensweise zur Priorisierung von Substanzen hinsichtlich ihres ökotoxikologischen Effektpotentials eignet sich sehr gut, Antibiotika mit dem höchsten Schadpotential zu identifizieren. Die Verschneidung der Kenntnis dieser Substanzen mit den Ergebnissen der SFA macht deutlich, dass mit Ausnahme der Makrolide, alle ökotoxikologisch priorisierten Antibiotika eine mangelhafte Prognosefähigkeit aufweisen. Die unvollständige Abbildung kritischer Stoffströme, wie z.B. Frachtspitzen, führt insbesondere im Fall der ökotoxikologisch priorisierten Substanzen zu einer Minderung der Aussagekraft des auf Verschreibungsdaten beruhenden Prognoseansatzes. An diesem Punkt ist in zukünftigen Betrachtungen anzusetzen, um die Qualität von Verschreibungsdaten zu verbessern, potentiell nicht erfasste Emittenten in die Betrachtungen einzubeziehen, sowie die Dynamik der Rückhalte- und Eliminationsprozesse in der Kanalisation adäquat beschreiben zu können. Die ergänzende Betrachtung weiterer Anlagentechnologien (z.B. Festbettreaktoren) kann zur Bestätigung der am Beispiel der Kläranlage Dresden-Kaditz gewonnenen Ergebnisse beitragen bzw. Unterschiede bei der Elimination von Antibiotika das Potential, die Problematik der Antibiotika und anderer Mikroschadstoffe bereits während der Planung von Abwasseranlagen berücksichtigen zu können.:Abstract 2 Danksagung 1 Table of Contents 1 Chapter 1 – Introduction 1 Scope 1 Goals and structure 3 Approach and Methods 5 Chapter 2 – Representative input load of antibiotics to WWTPs: Predictive accuracy and determination of a required sampling quantity 11 Introduction 14 Materials and Methods 16 Results and discussion 24 Conclusion 38 References 39 Chapter 3 – Mass flow of antibiotics in a wastewater treatment plant focusing on removal variations due to operational parameters 41 Introduction 45 Materials and Methods 47 Results and discussion 52 Conclusions 65 References 66 Chapter 4 – Species-related risk assessment of antibiotics using the probability distribution of long-term toxicity data as weighting function – a case study 71 Introduction 74 Materials and Methods 75 Results and discussion 86 Conclusions and summary 93 References 95 Chapter 5 – Environmental risk assessment of antibiotics including synergistic and antagonistic combination effects 99 Materials and Methods 104 Results 113 Discussion 120 Conclusions and summary . 125 References 126 Chapter 6 – Results and conclusions 129 Individual results 131 Aggregation of results 133 Final conclusions 134 References 139 Annex 1 – Supplementary material Chapter 2 141 Annex 2 – Supplementary material Chapter 3 147 Annex 3 – Supplementary material Chapter 4 159 Annex 4 – Supplementary material Chapter 5 177
Стилі APA, Harvard, Vancouver, ISO та ін.
49

Beyer, Christof [Verfasser]. "Applied numerical modeling of saturated, unsaturated flow and reactive contaminant transport : evaluation of site investigation strategies and assessment of environmental impact / vorgelegt von Christof Beyer." 2007. http://d-nb.info/984088210/34.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
50

Nixdorf, Erik. "Combining measurements, remote sensing and numerical modelling to assess multi-scale flow dynamics in groundwater-dependent environmental systems." Doctoral thesis, 2017. https://tud.qucosa.de/id/qucosa%3A31051.

Повний текст джерела
Анотація:
Groundwater flow modelling provides an important quantitative instrument for addressing issues related to the quantity and quality of groundwater and the connected water resources. Consequently, groundwater flow models have been developed and used ubiquitously in science to deepen the understanding of subsurface processes and their drivers as well as management and planning tools. The present work investigates how numerical models can be linked to field investigations and public databases to quantitatively approach questions in the area of groundwater research. The primary goal is to develop new, efficient ways to overcome limitations of the individual hydrological concepts for solving specific hydrological problems and to increase the understanding of practical applicability of different methods. For this purpose, tailor-made approaches were developed for different study areas covering diverse spatial scales: the hydrology of a small mining lake, the riparian aquifer at the scale of a single meander as well as the aquifer systems of a large-scale river basin in China. The first part of the work deals with the physical and mathematical modelling of water constituents balance in a meromictic mining lake in Lusatia. The capability of using a rather simple mass-balance model based on a sufficient dataset of field data to evaluate lake stratification and lake-groundwater interaction were shown. In the second part, a transient numerical groundwater flow model was developed for the riparian aquifer of a stream meander and was calibrated by three different salt tracer tests. The model was used to proof the reliability of subsurface travel times derived from time series analysis and to give insights in the riparian zone dynamics during changing hydraulic gradients. The third part of the work describes the methodology to conduct risk assessment of groundwater contamination on the large catchment scale of the Songhua River in China. A comprehensive literature study was conducted to get an overview about measurement data on water quality data in China. A three-dimensional numerical flow and mass transport model was applied to access the flow and matter transport dynamics in the aquifer system of a sub-basin considering changing groundwater exploitation scenarios. Consequently, numerical groundwater modelling was combined with processed remote sensing and web mapping service data to overcome field data limitations and to derive groundwater vulnerability, groundwater hazard and groundwater risk maps for the entire Songhua River Basin. Summarizing, this doctoral thesis could develop new methods of combining field measurements, data assimilation and aggregation from various sources and groundwater modelling strategies and successfully apply these methods to find solutions on problems of multiple scales and across water systems.
Die Grundwassermodellierung stellt eine wichtige wissenschaftliche Methode zur quantitativen Analyse von Fragestellungen zum Schutz der Menge und Güte der Grundwasserressourcen sowie der angeschlossenen Wasserkörper dar. Dementsprechend werden Grundwassermodelle sowohl für Planungs- und Bewertungszwecke im Wasserressourcenmanagement als auch zur wissenschaftlichen Erforschung der Prozesse im Untergrund entwickelt und angewendet. Die vorliegende Arbeit untersucht in diesem Rahmen, wie numerische Modelle, Feldmessungen und Daten generiert aus Fernerkundungsdaten und Webplattformen systematisch verknüpft werden können, um Fragestellungen im Bereich der Grundwasserforschung quantitativ zu beantworten. Das Ziel der Arbeit ist es neue effiziente Abläufe zu entwickeln, die die Limitierung der einzelnen Methoden überwinden und diese auf deren Anwendbarkeit für die Lösung spezifischer hydrologischer Probleme zu analysieren. Zu diesem Zweck wurden in dieser Doktorarbeit fallspezifische Lösungen für verschiedene Untersuchungsgebiete entwickelt, die sowohl in der räumlichen Skale als auch in den zu untersuchenden hydrologischen Fragestellungen eine große Diversität aufweisen. Im ersten Teil der Arbeit wurde die Massenbilanz von Wasserinhaltsstoffen in einem meromiktischen Tagebaurestsee im Lausitzer Revier durch physikalische und mathematische Modellierungsmethoden untersucht. Dabei konnte gezeigt werden, dass auf Basis einer gewonnenen mehrjährigen Zeitreihe von Messdaten ein einfaches Massenbilanzmodell in der Lage ist, sowohl Seeschichtungs- als auch Grundwasseraustauschdynamiken quantitativ zu beschreiben. Der zweite Teil der Arbeit umfasst die Entwicklung eines transienten numerischen Grundwassermodells für den quartären Uferaquifer im Bereich eines Flussmäanders der Selke welches anhand von Daten aus mehreren Salztracertests kalibriert wurde. Das Modell wurde dafür verwendet die transienten Verweilzeiten in der gesättigten Zone des Mäanderbogens unter dem Einfluss dynamischer hydraulischer Bedingungen zu untersuchen. Die Ergebnisse wurden im Anschluss mit Verweilzeiten verglichen, die aus der Analyse der zeitlichen Verschiebung von gemessenen elektrischen Leitfähigkeitszeitreihen zwischen Fluss und Grundwassermessstellen gewonnen wurden. Durch dieses kombinierte Verfahren konnten sowohl die Beschränkungen der zeitreihenbasierten Verweilzeitberechnung aufgezeigt als auch ein tieferes Systemverständnis für die Interaktionsdynamiken zwischen Grund- und Flusswasser auf der Mäanderskala gewonnen werden. Der dritte Teil der Arbeit beschreibt die Vorgehensweise für die Bewertung des Grundwasserkontaminationsrisikos im Einzugsgebiet des Songhua Flusses in China. Eine umfassende Literaturstudie wurde durchgeführt, um einen Überblick über die Verfügbarkeit von Messdaten zur Belastung der Wasserressourcen Chinas mit organischen Schadstoffen zu erhalten. Danach wurde für ein Teileinzugsgebiet ein dreidimensionales numerisches Grundwassermodell auf Basis der vorhandenen hydrogeologischen Daten aufgebaut. Dieses wurde dazu verwendet die Änderungen im Stofftransports und den Schadstoffkonzentrationen innerhalb des Aquifersystems unter steigenden Entnahmeraten zu analysieren. Basierend auf diesen Studien wurden auf der Skale des Gesamteinzugsgebiets, um die beschränkte Verfügbarkeit von Felddaten auszugleichen, die Ergebnisse der numerischen Grundwassermodellierung mit Fernerkundungsdaten und Webdatenbanken in einem Indexsystem kombiniert mit dem für die oberflächennahen Aquifere Vulnerabilität, Gefährdungspotential und Verschmutzungsrisiko in einer räumlichen Auflösung von 1 km² bestimmt wurden. Zusammenfassend konnten durch die vorliegende Doktorarbeit neue passgenaue Methoden zur effektiven Kombination von in-situ Messungen, der Datenerhebung und Datenintegration aus vielfältigen Datenquellen sowie numerischen Grundwassermodellierungsstrategien entwickelt und zur Lösung der untersuchten hydrologischer Fragestellen auf den verschiedenen Skalen und über die Grenzen der einzelnen hydrologischen Teilsysteme hinaus erfolgreich angewandt werden.
Стилі APA, Harvard, Vancouver, ISO та ін.
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії