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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
841

The Role of Uni- and Multivariate Bias Adjustment Methods for Future Hydrological Projections and Subsequent Decision-Making / Rollen av uni- och multivariata biasjusteringsmetoder för framtida hydrologiska projektioner och efterföljande beslutsfattande

Liebenehm-Axmann, Anna Merle January 2024 (has links)
Climate models are essential for generating future climate projections. However, due to simplifications, the models can produce systematic differences between output and reality, which is referred to as model bias. Bias adjustment methods aim to reduce this error, which is important for making future projections more reliable. Here, the suitability of four different bias adjustment methods was tested: distribution-based (Distribution Scaling (DS), Quantile Delta Mapping (QDM)) and non-distribution- based methods (Copula, Multivariate Bias Correction (MBCn)), of which each one univariate and one multivariate approach. The methods were assessed on climate future projections together with a non bias adjusted data set, focusing on their impacts on hydrological modelling simulations. For this, 16 hydrological signatures were analysed and categorized into: 1) water balance and flow dynamics, 2) seasonal behaviour of the flow, 3) low flow characteristics and 4) high flow characteristics. The assessment was carried out based on 50 catchments in Sweden, 10 climate models and one hydrological model. Most noticeable differences were observed between distribution-based and non-distribution-based methods, rather than between univariate and multivariate methods. Bias adjustment methods introduce half as much variation as climate models, catchments contribute substantially more to the projected signatures. Specific hydrological signatures differed regionally, such as changes in the average spring streamflow magnitude and greater bias adjustment variations in low- and high-flow frequencies, compared to varia- tions among catchments, suggesting a shift in the frequency of extreme streamflow events in the future. The choice of bias adjustment method impacted ’High flow characteristics’ the strongest. The Copula method deviated in the trend analysis by utilizing an existing trend. This research prompts further exploration of variation between current and projected future climate, or the inclusion of other variables that might impact projections, to determine the necessity of the methods. / Vi befinner oss i en tid av klimatförändringar. Det blir mer och mer synligt och klimatet kommer förändras i närtid och långt fram i tiden. Men hur exakt kommer det vara i slutet av detta århundrade? För att förutspå det, används klimatmodeller. Dock kan klimatmodeller bara ge en uppskattning om hur det kommer se ut, eftersom de måste förenkla jordsystem och klimat genom simplifieringar och antaganden, för att kunna beräkna projektionen. Det betyder att klimatprojektioner är ingen särskilt exakt förutsägelse. För att projicera framtidens vattenföring i en förändrande klimat, behöver an först modellera framtidens klimat och ut ur det modellera framtidens hydrologiska processer genom hydrologiska modeller. Kombinationer av flera modelltyper kallas modellkedja. För att projicera framtidens klimat, behövs en hel modell-kedja som består av klimatmodeller och hydrologiska modeller. Ju fler delar en modell-kedjan består av, desto osäkrare blir projektionen. Osäkerheten kallas systematiskt och slumpmässigt fel, kort bias. För att förbättra projektionen kan man inkluderar en så kallat bias korrektions metod, vars syfte är att minska biasen med en massa ekvationer och underliggande algoritmer. Det finns flera olika metoder, baserade på olika algoritmer, som beroende på algoritmernas innehåll är mer eller mindre komplicerad.  Jag undersökte i det här projektet, om det gör en skillnad, vilket bias korrektur metod man använder för att förbättra sitt klimat projektion. Det kan, t.ex. vara intressant att veta, när man måste bestämma sig mellan olika bias korrektur metoder som innehåller olika nivåer av komplexitet som användaren måste förstå sig på för att beräkna och korrigerar dataset som är utdatan från klimatmodellerna. För att testa det, tog jag ett existerande stort dataset (bestående av 4 olika bias korrektur metoder och ett dataset som inte var bias korrigerad, med 10 stycken klimatprojektioner för 50 avrinningsområden jämt utspridda över hela Sverige). För att kunna ge en omfattande överblick av framtidens klimat, beräknade jag flera, så kallade hydrologiska signaturer av vattenföringens karakteristik. De signaturer testades statistiskt för att visar avvikande och liknande betedde.  Metoder som korrigerar systematiskt fel betog sig ganska lika varandra, dock introducerades ungefär hälften så mycket variation som hos de 10 testade klimatmodeller, däremot introducerade de 50 flodbäcken mycket mer variation än bias korrektur metoderna, förutom vissa undantag. Jämförelsen föreslår en förändring i vårflöde och ett betydligt skifte i extremflöden i framtiden, jämfört med dagens flöde i älvarna. Det syns att det som blivit påverkat mest av från valet av bias korrektur metoder är kategorin "hög flod drag".  Det här projektet är bara en liten del av en större forskning, och det finns mycket kvar att studera. I framtidens forskning skulle det vara intressant att jämföra skillnaden mellan dagens avloppet och i framtiden och hur stor skillnaden är, jämfört med styrkan av variationen mellan de testade bias korrektur metoder. Därmed kunde man minska forskningsgapet ytterligare, och göra ett noggrant konstaterande i samband med olika bias korrektur metoder och om valets betydelse.
842

Socio-Ecological Resilience: ‘Weaving’ to scale Nature-based Solutions

Hussain, Sally, Carolina, Obara, Seefeld, Leon, Tjoelker, Tijn January 2022 (has links)
The sustainability challenge is a complex interplay of interconnected challenges that requires an integrated and systemic approach. Nature-based Solutions (NbS) are seen as a key tool for addressing such challenges but are currently not mainstreaming and scaling to the landscape level. The emerging leadership practice of Weaving is believed to help cohere fragmented change-making efforts and increase the adaptive capacity and resilience of socio-ecological systems. However, scientific research on NbS and Weaving is scarce and studies on their intersection are non-existent.  To investigate how Weaving practices could foster the conditions for scaling NbS to the landscape level, rapid literature reviews and semi-structured interviews were conducted with academic experts, Weaving practitioners, and grass-root entrepreneurs. On this basis, two conceptual frameworks were iteratively developed that serve as a basis for two practical toolkits. They comprise (1) seven barriers and nine enablers for scaling NbS to the landscape level and (2) a Weaving working definition and five core Weaving practices.  There are indications that Weaving practices have the potential to address several of the barriers and enablers for scaling NbS if approached with a systematic lens. Ultimately, interconnected challenges, such as barriers and enablers to scaling NbS, require interwoven approaches as provided by Weaving.
843

Assessing the viability of methylene blue titration for quantifying Bentonite in till soils : A case study from the Blaiken mine complex in Sorsele municipality, Sweden / Utvärdering av metylenblå titreringsmetodens lämplighet för att kvantifiera bentonit i moränjordar : En fallstudie från Blaiken-gruvkomplexet i Sorsele kommun, Sverige

Magnusson, Noel January 2024 (has links)
Abandoned mines present considerable environmental risks through the release of toxic metals, particularly into adjacent water bodies. The implementation of reliable geotechnical cut-off walls containing bentonite stands as a crucial strategy in mitigating environmental groundwater contamination. This study evaluates the viability of employing the methylene blue titration method to quantify bentonite content in till samples, with the objective of verifying the assumed bentonite content (3.5%) and exploring the impact of sample preparation on bentonite content determined through titrations. Bentonite, known for its swelling properties and high cation exchange capacity, was introduced into till samples both in laboratory settings and on-site. The methylene blue titration method was utilized to measure bentonite content in these samples. Laboratory results indicated significant variations in bentonite content depending on the sample preparation method, with methods employing soil homogenization proving more effective in quantifying bentonite accurately. The study's findings support the hypothesis that the methylene blue method can reliably quantify bentonite in till soil samples with the correct preparation in a laboratory environment. On-site analysis exhibited larger variations and deviations in bentonite content quantifications compared to laboratory-based incorporations. Additionally, on-site incorporated samples demonstrated a statistically significant difference in bentonite content compared to laboratory-incorporated samples, highlighting the method's sensitivity and need for future research. This research contributes valuable insights into leveraging methylene blue titration for quantifying bentonite in till soils, crucial for establishing geotechnical barriers to control toxic metal output from mines.
844

Svenska högskolestudenters köpbeteenden : - en undersökning om klädkonsumtion på Generation Z

Delin, Jonna, Werner, Josefin January 2024 (has links)
Den här studien undersöker vad som påverkar beslutsfattandet för svenska högskolestudenter ur Generation Z när de gör inköp av kläder, samt vilka konsekvenser det leder till gällande konsumtionen av second hand och fast fashion. Studien undersöker även hur miljömedvetenhet påverkar dessa beslut. Studien är baserad på en enkätundersökning, där frågorna är baserade på teorierna Theory of Planned Behaviour och the Value-Action gap. Med hjälp av enkäten undersöks attityder till olika val samt hur deltagarna agerar. Studien utgår även från tillgänglig litteratur, bestående av vetenskapliga källor och rapporter. Resultaten visar att miljömedvetenhet har en stor inverkan på hur konsumenter agerar, samt att pris, tillgänglighet, kvalitet, storleksutbud och hållbarhet är avgörande när konsumenten fattar sina beslut. En jämförelse mot hållbarhetsmål 12 ur FN:s Agenda 2030, som anses aktuellt för studien, visar på att svenska högskolestudenter ur Generation Z konsumerar förhållandevis hållbart och ligger relativt bra i linje med de uppsatta målen. Resultaten visar även att den generella inställningen till fast fashion är negativ, och inställningen till second hand generellt är positiv. Detta ser lovande ut inför framtiden, och resultaten tyder även på att större medvetenhet kring miljöfrågor leder till mer hållbara val och konsumtionsmönster. / This study examines factors influencing decision-making among Swedish university students from Generation Z when purchasing clothing, as well as the consequences this has on the consumption of second hand and fast fashion. The study also explores how environmental awareness affects these decisions. The study is based on a survey, in which the questions are based on Theory of Planned Behaviour and Value-Action Gap. The survey explores attitudes towards different choices and how participants act. The study also draws from available literature, consisting of scientific sources and reports. The results show that environmental awareness has a significant impact on consumer behaviour, and that price, availability, quality, size range, and sustainability are crucial when consumers make their decisions. The results were compared with several sub-goals of Sustainable Development Goal 12 from the UN's Agenda 2030, which are considered relevant to the study. The results also indicate that the general attitude towards fast fashion is negative, and the attitude towards second hand is generally positive. This looks promising for the future, and the results also suggest that greater awareness of environmental issues leads to more sustainable choices and consumption patterns.
845

Reconnecting to Food: Can Sámi Indigenous Ontology help guide Sweden to a Sustainable Food System?

Kastner, Livia Lara January 2024 (has links)
Sustainable food systems are a crucial objective in the 2030 agenda as food security is under threat in large parts of the world, either currently or in the near future. Food systems connect many of the timely challenges the world faces today, touching upon various dimensions. This multidimensional character causes the search for adequate solutions to span a broad interdisciplinary field and to direct research towards new modes of knowledge, such as those carried by Indigenous peoples' traditional cultures and beliefs. Indigenous people’s food systems are considered to offer valuable insights into sustainable food practices and improve the understanding of the connection between nature and humans. In Sweden, the National Food Strategy is the guiding framework that aims for a transformation to a sustainable food system in line with the objectives of the 2030 agenda. The need for knowledge generation is recognised but refers to new and mainstream objectivist modes. Sámi Indigenous perspectives as a potential source are not recognised. Therefore, the aim of this thesis is to identify potential learnings from Sámi Indigenous perspectives to strengthen the Swedish idea of a sustainable food system. To reveal learnings, a policy analysis is carried out guided by Indigenous methodology. The analysis is rooted in two core documents, namely the Sámi environmental framework (Eallinbiras) and the Swedish National Food Strategy. Commonalities and differences between Sámi perspectives and Swedish food policy are identified and discussed. Additionally, in line with Indigenous methodology, two consultations with local Sámi experts were carried out to seek guidance on the interpretations and findings of the results. Overall, it is concluded that there are various touching points where Sámi ontology could facilitate a strengthening of the food strategy and help realise the desired goals. Mainly, such involvement could steer approaches from a regulatory- to a relationship-oriented character, facilitate a deepened holistic perspective, and assign greater value to the environment, resulting in improved resilience. To realise an integration of Sámi perspectives into Swedish food strategy requires respect and the safeguarding of Indigenous rights. Certainly, many political, ontological and epistemic challenges present themselves for such an endeavour. However, some interests appear to be shared, and the potential for valuable learning is found to exist. Further research is needed to derive more concrete, practical implications and carry out participatory models to realise an integration of Sámi ontology to strengthen Swedish food policy.
846

GIS-based MCDA for Integrated Risk Assessment and Prioritization of High-Risk Areas in the Göta River Valley

Forslund, Linda January 2024 (has links)
Climate change will bring more precipitation in Northern Europe and Sweden.Increasing precipitation will cause more floods, which will increase landslide risks. Inthe Göta river valley there are high landslide risks due to the thick layer of clay andquick clay present there. The river valley has been the home of numerous industriesfor a long time, which unfortunately have left large areas with contaminated soils alongthe river. The Göta river is the only outlet for Sweden's largest lake, called LakeVänern. With increasing precipitation, the water level of the lake will rise. This willlead to a larger tapping of the lake, to not cause floods around the lake. A largertapping will lead to higher flood and landslide risks in the river valley and thusincreasing the risk for contaminated soils entering the river.This study seeks to provide a comparison of two analyses where flood risk classes andheight above water level, functioning as flood uncertainties, as well as contaminatedsoil criteria are used in one of the analyses but not the other, to see if there is a difference.The study also seeks to show where along the river there are high risk areas inneed for climate adaptation measures to reduce risks.The method used was a multi-criteria decision analysis (MCDA) with the Analytichierarchy process (AHP) technique, to include several criteria in the analysis, pairwisecompare the criteria, and calculate their relative weights. The method was utilizedwith Geographic Information System software and AHP software. The robustness ofthe analyses were controlled by performing a One-Factor-at-a-Time sensitivityanalysis.The result of this study was the findings of four areas with high risk values along theGöta river. Three of those areas were found in both performed MCDA's. The fourtharea was only found in the second MCDA where the three additional criteria wereincluded in the analysis.The conclusion of this study is that the areas with the highest risks in relation to flood,landslide, and contamination risks are located in the localities of Lilla Edet, Älvängen,Sure, Göta, and in the city of Gothenburg. Also, there is a difference in the resultswhen including the three additional factors, another area is highlighted as having highrisks. The method used in this study makes it clear that the usage of five or eight criteriacan produce results that are similar to each other. However, by using eight criteriainstead of five and thus including additional risks that are connected with each other,there is an impact on the result, which becomes more precise.
847

Whose Voices: Environmental Justice in the Plastics Treaty Negotiations

Pattison, Anna January 2024 (has links)
Plastics pollution is a global planetary threat to both humans and the environment, leading to injustice throughout its lifecycle and disproportionately affecting the most vulnerable. The United Nations Environmental Assembly adopted Resolution 5/14 to create a legally binding instrument to end plastics pollution, known colloquially as the Plastics Treaty. The treaty is currently under negotiation, and the implicit understandings of justice that will be incorporated will significantly impact the outcome of the treaty. This thesis employs critical discourse analysis and key stakeholder interviews to examine the various justice narratives and framings of actors in the treaty through an environmental justice lens. Additionally, the role of power in shaping these narratives is examined from a critical and decolonial perspective. My research demonstrates the value of a critical approach in addressing power dynamics and normative concepts such as justice in social-ecological and sustainability research. This study identifies three distinct discourses, each offering different problematizations of plastics and justice framings. The analysis reveals competing definitions of just transition, a disconnect between the recognition of Indigenous Knowledge and the rights of Indigenous People, and underdeveloped gender and intersectional considerations. Furthermore, this thesis highlights the enduring influence of colonial dynamics on plastics pollution, potentially reinforcing waste colonial relations in the Plastics Treaty. Finally, this thesis contends that problematizing plastics as a human rights issue offers a valuable approach to address these shortcomings, thereby enhancing the treaty's potential for promoting justice by ensuring that the voices of those most affected are heard.
848

Climate Impact Resilience and Community Development : Adaptive Solutions and Challenges in Rural Southern Africa – Coastal Mozambique as an Example

Vincent, Judith January 2024 (has links)
Many African communities are significantly affected by climate change, despite being small contributors to the world's emissions. In Mozambique, the rural Southern region is more vulnerable to climate instability than other rural areas in the country. The purpose of this study is to look at factors that can be vital when deciding whether to stay or to migrate, such as resilience, social sustainability, and development opportunities and challenges. The data was collected through ethnographic fieldwork in a rural community on the Mozambican coast, with the villagers' perspective in the centre of what makes the place relevant to their daily lives. What makes the study village sustain and thrive are the development processes of weather-resistant buildings and developing ideas for more sufficient farming, health, and education. Even though some people migrate from the village to the cities, people often come back as challenges in the village are more familiar and simpler to deal with, development ideas represent a hopeful future for the village, and the villagers' want to live in their community simply because it is home.
849

Nitrogen Uptake by Vegetation in the Wakkerstroom Wetland, South Africa

Dufbäck, Emma January 2019 (has links)
The lack of proper wastewater treatment inhibits the social and economic development in many communities. The South African town Wakkerstroom is an example where wastewater is first treated before it is released. Due to the lack of technical expertise and funding to manage the sewage disposal system, a large part of the wastewater goes directly, without any treatment, into a stream feeding the Wakkerstroom wetland. The wetland purifies the wastewater and provides clean water downstream, thus is indispensable for its detoxification capacity. One relatively cheap method to determine the absorption capacity of a wetland with respect to nitrogen loading is to investigate the nitrogen uptake by the wetland vegetation. In this study, the nitrogen uptake of the vegetation in the Wakkerstroom wetland during the growing seasons between the years 2000-2018 was investigated by using harvested biomass and its nitrogen content as a proxy. The interannual variability of Net Primary Production (NPP) was calculated using a Light Use Efficiency (LUE) model for the period 2000-2018. The NPP derived with LUE-modelling was compared to NPP based on an end-of season harvest of biomass in March 2019. The nitrogen content and carbon and nitrogen (C:N) ratio were determined in the harvested biomass by carbon and nitrogen content analysis. The annual nitrogen uptake of the growing seasons between the years 2000-2018 was subsequently determined by multiplying the calculated NPP by the fraction of nitrogen found in the harvested material. The NPPtot based on harvested biomass (NPPharvest) towards the end of the growing season 2018/2019 was estimated to be 2.01 kg‧m-2‧season-1. The NPPtot calculated from LUE modelling (NPPLUE) varied between 0.49-1.64 kg‧m-2 for the growing seasons between 2000-2018. NPPharvest was between 1.2-4 times higher compared to NPPLUE, probably due to overestimation of NPPharvest because of biomass sampling of more than one-year production, or underestimation of NPPLUE due to a low maximum radiation conversion efficiency factor, εmax. The community mean nitrogen (N) content found in the biomass harvested aboveground was 1.29 % for the Phragmites community and 1.00 % for the Typha community. The nitrogen uptake of the vegetation was estimated to vary between 6.10-20.5 g N∙m-2 per growing season between the years 2000-2018. / Bristen på adekvata reningstekniker för att behandla avloppsvatten hämmar den sociala och ekonomiska utvecklingen i många samhällen. Den sydafrikanska staden Wakkerstroom är ett exempel där avloppsvatten först renas innan det släpps ut. På grund av brisen på teknisk kompetens och finansiering att hantera reningsverket som avlägsnar avloppsvatten så läcker en stor del av det orenade avloppsvattnet ut i en våtmark i Wakkerstroom via en närliggande å. Våtmarken är av regional betydelse för sin reningskapacitet då den renar avloppsvattnet och förser användare nedströms med rent vatten. En viktig aspekt för att bestämma en våtmarks reningskapacitet med avseende på kväve (N) är att undersöka växternas kväveupptag i våtmarken. Kväveupptaget hos växterna i våtmarken i Wakkerstroom under växtsäsongerna mellan år 2000–2018 undersöktes genom att använda skördad biomassa och dess kväveinnehåll som proxy. Den årliga variabiliteten hos nettoprimärproduktionen (NPP) beräknades genom att använda en LUE (Light Use Efficiency)-modell för perioden 2000-2018. NPP framtaget med LUE-modellering jämfördes med NPP baserat på biomassa skördad i slutet av växtsäsongen i mars 2019. Kväveinnehållet och kol-kväve (C:N) kvoten bestämdes hos den skördade biomassan genom en kol- och kväveanalys. Det årliga kväveupptaget under växtsäsongerna mellan 2000–2018 togs därefter fram genom att multiplicera beräknad NPP med kvävefraktionen erhållen från den skördade biomassan. NPPtot framtaget med biomassa skördad i slutet av växtsäsongen 2018/2019 (NPPbiomassa) uppskattades vara 2,01 kg‧m-2‧säsong-1. NPPtot beräknat med LUE-modellering (NPPLUE) varierade mellan 0,49–1,64 kg‧m-2 under växtsäsongerna mellan år 2000–2018. NPPbiomassa var 1,2–4 gånger högre i jämförelse med NPPLUE, vilket troligtvis berodde på att NPPbiomassa överskattades på grund av att mer än en årsproduktion av biomassa skördades, eller för att NPPLUE underskattades på grund av ett för lågt värde på den maximala effektivitetsfaktorn εmax valdes. Medelvärdet för kväveinnehållet erhållen i biomassan skördad ovanför vattennivån var 1,29 % för Phragmites-samhället och 1,00 % för Typha-samhället. Kväveupptaget hos växterna varierade mellan 6,10–20,5 g N∙m-2 per växtsäsong mellan år 2000–2018.
850

Skyddsinfiltrationens influensområde för en fallstudie : - modellering och osäkerheter

Sigfridson, Marcus January 2019 (has links)
För att uppskatta influensområdet till följd av skyddsinfiltartion finns ett antal analytiska modeller att tillämpa. Dessa modeller tar hänsyn till parametrar så som hydraulisk konduktivitet och magasinkoefficient, men de följer också med en rad antaganden som i praktiken inte kan uppfyllas. En alternativ tillvägagång för att bestämma influensområdet är därför med hjälp av numeriska modeller, som i större grad kan göras platsspecifika. Numeriska modeller är till följd av detta mer tidskrävande och behöver mer indata. I denna studie undersöktes vilken metod som är bäst lämpad för att bestämma skyddsinfiltrationens influensområden för en fallstudie i Bromstens industriområde, belägen cirka 15 km nordväst om Stockholm centrum. Två numeriska modeller med varierande underlag av platsspecifika data utvecklades över områdets geologi och grundvattenmagasin för att kunna simulera grundvattennivåer med och utan infiltration. Utöver detta beräknades influensområdet med fyra analytiska modeller. Modellerna testades sedan utifrån olika scenarion, där såväl dataupplösning som den platsspecifika kännedomen över området stegvis ökades. Platsspecifika data tillkom till följd av geotekniska undersökningar och hydrogeologiska tester. Studien ämnar även att besvara vilken data som är av störst vikt för att bestämma influensområdet med de analytiska respektive numeriska modellerna samt vilka skillnader som uppstår mellan analytiskt beräknade influensområden och numeriskt simulerade influensområden. Resultaten visar att de numeriska modellerna i huvudsak är känsligast med avseende på den hydrauliska konduktiviteten, samt att den enklare numeriska modellen är känslig för magasinkoefficienten, något som indikerar att denna modell inte uppnår jämvikt i enlighet med vad som observerats i fält. Utöver detta stod det klart att vattenavgivningstalet inte hade någon nämnvärd inverkan på resultaten. Bland de analytiska modellerna råder den största känsligheten i magasinkoefficienten, följt av konduktiviteten. För Sichardts formel, som inte tar hänsyn till magasinkoefficienten var konduktiviteten den känsligaste parametern. Akvifärens mäktighet, vilken reviderades mellan scenario 2 och 3, hade ingen betydande inverkan på de analytiska modellerna. Vidare visade infiltrationstestet på stora skillnader i skyddsinfiltrationens influensområde med avseende på de olika modellerna och dataunderlaget. Den minsta avvikelsen mätt i residualer observerades för den komplexa numeriska modellen under scenario 4, vilket motsvarar det scenario då dataunderlaget var som störst. Trots att detta scenario tillsammans med modell anses vara det dyraste fallet, anses detta vara det bästa och samtidigt mest tillförlitligt metoden för att uppskatta skyddsinfiltrationens influensområde. / To evaluate the area of influence due to artificial infiltration several analytical models are available. Some of the parameters taken into account by these models are the hydraulic conductivity and storage coefficient, but with these models some assumptions, which in reality cannot be fulfilled, are made. An alternative approach to evaluate the area of influence is therefore with numerical models, which in a greater extent account for the site-specific conditions. Due to this, numerical models are more time consuming and require more input data. This project aims to investigate the most effective approaches to evaluate the area of influence due to artificial infiltration for a case study in Bromsten, located 15 kilometers northwest of Stockholm. Two numerical models, with different background data due to the extent of site knowledge, were developed to represent the site's geological settings and groundwater properties to simulate the groundwaterlevels with and without infiltration. Moreover the area of influence were calculated with four analytical models. All of the models were then applied on four different scenarios, in which the data resolution and the site knowledge increased. Site-specific data was added as a result of geological surveys and hydrogeological tests. The study also aims to answer which data is most important in order to determine the area of influence with analytical and numerical models and what differences there are between the analytical solutions compared with the numerical solutions. Among the methods investigated, constructing a more complex model with data from scenario 4, the scenario with the greatest data supply, resulted in the most reliable results and was therefore the best method and the method to choose for this case-study. Other results indicated that the numerical models first of all are sensitive to the conductivity and that the more simpel numerical model is sensitive to the storage coefficient as well. The last result shows that this model does not reach the steady state conditions as observed in field, which highlights the importance of goetechnical investigation for the numerical models. Moreover none of the numerical models were sensitive to the specific yield. Among the analytical models the storage coefficient was the most important followed by the conductivity. For one of the analytical models (Sichardts formula) the conductivity was the most sensitive parameter. The thickness of the aquifer had no significant impact on the analytical models.

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