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

Study on Assessment and Adaptation to Saltwater Intrusion under the Impacts of Tide, Sea-Level Rise, Flow and Morphological Changes in the Vietnamese Mekong Delta / ベトナム・メコンデルタにおける塩水遡上に及ぼす潮汐・海面上昇および流況・河道地形変化の影響評価および適応策に関する研究

Nguyen, Thi Phuong Mai 23 May 2022 (has links)
京都大学 / 新制・論文博士 / 博士(工学) / 乙第13491号 / 論工博第4200号 / 新制||工||1785(附属図書館) / (主査)教授 角 哲也, 准教授 Kantoush Sameh, 准教授 竹門 康弘 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
12

Saltwater Intrusion and Vegetation Shifts Drive Changes in Carbon Storage in Coastal Wetlands

Charles, Sean Patrick 27 June 2018 (has links)
Coastal wetlands protect coastlines through efficient storage of organic carbon (OC) that decreases wetland vulnerability to sea level rise (SLR). Accelerated SLR is driving saltwater intrusion and altering vegetation communities and biogeochemical conditions in coastal wetlands with uncertain implications. We quantified changes in OC stocks and fluxes driven by 1) saltwater and phosphorous intrusion on freshwater and brackish marshes, 2) vegetation along an experimental saltmarsh to mangrove gradient, 3) saltwater intrusion and vegetation change across a marsh to mangrove ecotone, and 4) vegetation change and mangrove forest development along a marsh to mangrove ecotone. Increasing salinity in freshwater marshes decreased root biomass and soil elevation within one year. In brackish marshes, increased salinity decreased root productivity and biomass and increased root breakdown rate (k), while added salinity did not increase elevation loss. In our experimental marsh-mangrove ecotone, mangrove vegetation promoted higher organic carbon (OC) storage by increasing above and belowground biomass and reducing organic matter k. However, mangroves also increased belowground k, and decreased allochthonous marine subsidies, indicating the potential for OC storage trade-offs. In the Southeast Everglades, we identified strong interior-coastal gradients in soil stoichiometry and mangrove cover. Interior freshwater soil conditions increased k, while total soil OC stocks decreased toward the coast indicating that saltwater intrusion is driving large scale soil OC loss. In the southeast Everglades, mangrove expansion increased root biomass and root productivity, but did not mitigate the overall loss of OC stocks toward the coast. Similarly, in the southwest Everglades, saltwater intrusion drove a decrease in soil OC. However, mangrove encroachment drove a rapid recovery and increased OC stocks. Mangrove encroachment doubled aboveground biomass within the last ten years, increased it 30 times in the last 30 years, and doubled belowground biomass after 20 years. Our research shows that 1) moderate saltwater intrusion without mangrove encroachment will lead to a loss in OC stocks and potentially lead to wetland elevation loss and submergence, 2) in the absence of a change in saltwater intrusion, mangrove expansion can enhance OC storage 3) mangrove expansion can mitigate OC loss during saltwater intrusion, but this pattern depends on mangrove recruitment and ecosystem productivity.
13

A Risk Assessment Analysis : The risk of saltwater intrusion into freshwater wells and the effects of a futuresea level rise on the Baltic Sea island of Öland

Eriksson, Marcus January 2017 (has links)
Freshwater is essential for a functional society and the human well-being. However, it should not be taken for granted. Freshwater aquifers in coastal are subject to current and future risk of becoming saltwater contaminated – reaching a tipping point. Freshwater security on islands is vulnerable. The aim of this empirical study is to identify the effects of a 2-meter sea level rise and the current risk of well salinization at the Baltic Sea island of Öland, Sweden. A Geographical Information System (GIS) was used to conduct a quantitative risk assessment analysis. Natural and physical parameters affect the risk of intrusion into wells including hydrology, geomorphology, and climatology. Anthropogenic causes and climate change also add to the risk of salinization. However, they are not included in the quantitative study. The spatial distribution of the current risk is mapped in this study and can be used as a tool to identify wells at risk. Moreover, a future sea level rise has been visualized and show that 3% of all wells on the island will get directly inundated along with 5% of the total land area. Important land such as urban areas, nature reserves, and animal protection areas will get inundated including the loss of environmental and socio-economic values. A precautionary approach needs to be implemented in future planning since many wells are already at risk of salinization. The complexity of the problem is vast, and this study aims to fill the gaps in literature and previous research in a more multi-criterion way. Nevertheless, the political discussion urgently needs to address the topic and a mitigation and adaptation strategy must be on the agenda.
14

Investigation of the origin of salt in coastal aquifers and assessment of metals in the aquatic environment : River Drin and River Vjosa, Albania

von Bahr, Maximilian, Gomez Bergström, Ida January 2018 (has links)
The preservation of freshwater aquifers is one important task of managing natural resources today. Intrusion of saltwater from the sea into the groundwater might occur in coastal-near areas and can affect the freshwater quality negatively. One such risk area is the Adriatic coast line of Albania, a country predominantly rich in freshwater resources due to the numerous rivers flowing from the mountains in the east towards the sea. The coastal areas are mainly used for agricultural activities were groundwater is an important resource for irrigation purposes. This study was therefore partly conducted in Albania where samples of groundwater and river waters were collected from the river deltas of Drin and Vjosa in order to investigate the origin of the salt and to assess the bioavailable metal concentrations of nickel and zinc. Both on-site tests and off-site tests, in laboratories, were conducted. In the laboratory, the samples were analysed for oxygen and deuterium isotope data. The results were used to assess the origin of the oxygen content as the method of investigating the origin of the salt uses the oxygen isotope as a tracer. Anion and cation concentrations were analysed as well as the concentrations of metals. These were used as input data to Visual Minteq, a model used to calculate the metal speciation of waters, and a Biotic Ligand Model used to calculate the bioavailable concentrations and the HC5 concentrations. The isotope analysis yielded results similar to previous studies conducted in the nearby area indicating that the salt does not have oceanic origin but meteorological. The bioavailable concentrations were in most sample sites lower than the calculated HC5 concentrations indicating that there is a sufficient buffering system present even though there are several mining activities upstream of the sample sites that could have affected the water quality. This study concludes that the origin of salt is of meteoric origin and not from seawater intrusion. The bioavailable concentrations do not pose a threat as the concentrations are under the HC5 concentrations for all sites but one. In order to deepen the understanding and knowledge of the water qualities in these areas, future studies should focus on a continuous measuring period lasting for example over the whole year minimizing any seasonal variations of the sampled data. Other methods such as geophysical measures could also contribute to a wider analysis of the groundwater condition. / Grundvatten är en av de viktigaste naturresurserna vilket innebär att för att säkerställa en långvarig försörjning krävs en god förvaltning av befintliga akvifärer. I kustnära områden kan intrång av saltvatten från havet till grundvattnet påverka sötvattenkvaliteten negativt. Ett sådant riskområde är den Adriatiska kustlinjen i Albanien, ett land som är övervägande rikt på sötvattenresurser tack vare de många floder som rinner från bergen i öst mot havet i väst. Kustområdena används huvudsakligen för jordbruksverksamhet, där grundvatten är en viktig resurs vid bevattning. Denna studie genomfördes därför delvis i Albanien där prov av grundvatten och flodvatten hämtades från Drins och Vjosas floddeltan för att undersöka saltets ursprung och för att bedöma de biotillgängliga metalkoncentrationerna av nickel och zink. Vattenprover togs på ett urval av platser och testades direkt för omgivningsberoende parametrar samt analyserades vidare i laboratorier. I laboratoriet analyserades proverna med avseende på fördelning av syre- och deuteriumisotoper. Resultaten användes för att bedöma syreinnehållets ursprung, eftersom metoden för att undersöka saltets ursprung använder syreisotopen som spårämne. Anjon- och katjonkoncentrationer analyserades såväl som koncentrationerna av metaller. Dessa användes som inmatningsdata till Visual Minteq, en modell som används för att beräkna metallsammansättningen i vatten och en Biotic ligand model som användes för att beräkna de biotillgängliga koncentrationerna samt HC5-koncentrationerna. Isotopanalysen gav resultat som liknar tidigare studier utförda i det närliggande området vilket indikerar att saltet inte har oceaniskt ursprung utan meteorologiskt. De biotillgängliga koncentrationerna av nickel och zink var i de flesta fall lägre än de beräknade HC5-koncentrationerna, vilket indikerar att det finns ett buffertsystem, trots att gruvaktiviteter uppströms provplatserna skulle kunna ha påverkat vattenkvaliteten negativt.   Studien slutsats är att saltet i grundvattnet och flodvattnet är av meteoriskt ursprung och inte ett resultat av saltvatteninträngning från det Adriatiska havet. De biotillgängliga halterna av nickel och zink understiger HC5 halterna i samtliga fall utom ett.   För att fördjupa förståelsen och kunskapen om vattenkvaliteten i dessa områden bör framtida studier fokusera på en kontinuerlig mätperiod som till exempel sträcker sig över hela året vilket skulle minimera eventuella säsongsvariationer av insamlad data. Andra metoder så som geofysiska mätningar kan också bidra till en bredare analys av tillståndet i grundvattnet.
15

Saltwater intrusion and agriculture: a comparative study between the Netherlands and China.

Duan, Yuxin January 2016 (has links)
Saltwater intrusion, which can be facilitated by natural conditions, human activities and climate change, is a big threat to mankind from social-economic, environmental and ecological perspective. Agriculture, the largest consumer of water, is identified as both contributor and most vulnerable sector to saltwater intrusion, especially in coastal low-lying areas, with the increasing demands and competition of water owing to economic bloom, population growth and climate fluctuations. Sustainable water resource management is urgently needed owing to its essential in solving this issue. Hence this study is to deliver the understanding of linkage between saltwater ingress and agriculture and seek appropriate water resource management strategies in coastal low-lying areas to address saltwater intrusion and reduce its impacts on agriculture.   This study conducts a comparative case study between Texel, the Netherlands and Shouguang, China to specify the linkages between saltwater intrusion and agriculture with local features. The reasons, impacts and associated mitigations and/or adaptations of the issue, together with the legislation of each region have been investigated and compared.   The results show that for combating the saltwater intrusion and reducing the losses from agriculture, both study areas have adapted specific approaches. Among them similar approaches, despite different legislations and policies, such as developing alternative water resource (treated wastewater and rainwater) and saline agriculture are implemented by both of the regions. Through the comparison, each can learn the lessons from the other. The integrated water legislation together with its effective implementation, the strong involvements of different stakeholders and ecological approach to post-treat effluent of Texel can no doubt inspire Shouguang. While the highlights of counteract measures taken by Shouguang such separating rainwater from wastewater during collection and treatment, water diversion and development of special market to achieve high profit for saline products can obviously inspire Texel as well.   The analysis and comparison between these two case studies can reflect the general problems regarding to water management on saltwater intrusion and agriculture in all the regions that suffer from this problem. Hence, it is concluded that 1) integrated water legislation and management (with climate change considered and integrated as well) are the foundations, while water conservation should be core idea that always kept in mind; 2) strong involvements of different stakeholders and necessary supervision systems can guarantee the effectiveness of implementation; 3) all actions should be based on both technical knowledge and local-cultural knowledge; 4) self-sufficient approaches should be promoted at micro level to reduce the dependency on external water intrusion; 5) economic means should be carefully combined with environmental and ecological ways as well to achieve the goal of development of sustainability; 6) monitoring systems are of great significance.
16

Grundvattenförhållanden på delar av Nämdö : Inventering och analys i Östanvik och Sand

Svensson, Niklas Lihuvud, Risberg, Staffan January 2021 (has links)
Idag pågår det utredningar för upprättandet av en nationalpark och ett biosfärområde i Nämdöskärgården varav Östanvik och Sand antas tillhöra de områden som kan få en ökad exploatering i samband med detta. Det innebär ett ökat grundvattenuttag och en ökad belastning på grundvattenakvifererna. Projektet omfattar en inventering av Östanvik och Sands grundvattentillgångar. Inventeringen har inneburit undersökningar av tillrinningsområden till akviferer, akviferens storlek, maximal boendegrad, grundvattenuttag och risk för saltvatteninträngning. Resultatet visade att grundvattentillgången för Östanvik var tillräcklig för befintlig bebyggelse samt för viss framtida exploatering. Däremot visade resultatet att grundvattentillgången i Sand var begränsad och bedöms inte kunna belastas mer utan att vidta åtgärder som bättre lokalisering av brunnar och/eller avsaltningsanläggningar. Risken för saltvatteninträngning var hög för strandnära brunnar och något lägre för brunnar belägna längre bort från strandlinjen (>100 m). / A future establishment of a national park is planned in the Nämdö archipelago and an entrance to the park could possibly be established somewhere on Nämdö. At the same time, a biosphere reserve is planned for Nämdö and its surroundings, which could lead to an increased development in the area. With an increased development in the archipelago the strain on the already fragile groundwater assets intensifies. The aim of this project was to examine the groundwater situation in Östanvik and Sand, which is located on Nämdö, in order to evaluate how an increase of the groundwater outtake would affect the aquifers and the future groundwater assets. Using field studies, groundwater budget calculations, geotechnical investigations and calculations of the risk for salt water intrusion, an estimate of the local groundwater supply was done. The groundwater capacity in Sand was limited and considering the grade of development in the area further development would most likely impact the groundwater quality. In order to extract more groundwater, new wells would have to be established further away from the developed area and the shore. The groundwater capacity in Östanvik was adequate for the current grade of settlements and tourism, but also for a future increase of both these. In order to protect the existing wells in the area, new wells should be located away from the shore and in areas with good groundwater supply.  The results showed that Östanvik both had bigger aquifers and a currently smaller outtake than Sand and therefore is better suited for an expanded groundwater outtake. The risk for saltwater intrusion in both areas was shown to be relatively high with an increasing risk closer to the shoreline (<100m). In addition to other approaches, this risk can be reduced by a more constrained and scattered outtake in areas further away from the shore, but also by using desalinated seawater.
17

Changes in Soil Microbial Functioning in Coastal Wetlands Exposed to Environmental Stressors and Subsidies

Servais, Shelby M 11 May 2018 (has links)
Environmental perturbations are ubiquitous features of ecosystems and shape ecological structure and function. Climate change will alter the intensity and frequency of disturbances and expose ecosystems to novel combinations of useful inputs (subsidies) and harmful inputs (stressors). Coastal wetlands are particularly vulnerable to changing environmental conditions and are increasingly exposed to effects of interacting subsidies and stressors. In particular, the Florida Coastal Everglades, which has experienced accelerated change due to a history of water management practices, is vulnerable to new disturbances associated with climate change. The low-lying Florida Everglades faces multiple disturbances from storm surge, nutrient enrichment, and sea-level rise which will influence its responses to future environmental perturbations. Microbial communities are often used to characterize environmental change because of their high surface area to volume ratio, permeable membrane, and quick turnover rates. Therefore, assessing how microbial function changes can provide insights into how subsidies and stressors interact to alter biogeochemical cycles. I tested how nutrient enrichment can alter ecosystem responses to stress and found that it did not promote recovery in mangrove plants. I examined how long-term exposure to salinity and phosphorus (the limiting nutrient in the Everglades) affected microbial enzyme activity and found that salinity alone acts as a suppressor of enzyme activity but phosphorus addition can mitigate salinity stress in sawgrass soil. I tested how pulses of salinity can affect the microbially-mediated breakdown of organic material and found that the microbial community was functionally redundant and unaffected by saltwater pulses; however, microbial activity was consistently lower in the brackish marsh compared to the freshwater marsh. I investigated how gradients of salinity and phosphorus affected freshwater and brackish soils and determined previous exposure to saltwater intrusion dominates affects microbial function and soil composition. Across these experiments, I found that environmental perturbations alter the microbial-mediated processing of nutrients and carbon, and legacies of previous disturbances influence the microbial response to new disturbance regimes.
18

Caractérisation multi-échelle des structures hydrogéologiques en contexte volcanique insulaire par électromagnétisme héliporté : application à l’île de La Réunion / Multi-scale characterization of groundwater structures in shied volcano island with airborne electromagnetics : application in La Réunion Island

Dumont, Marc 16 April 2018 (has links)
L’île de La Réunion a été couverte par une vaste campagne de géophysique héliportée en 2014. Le dispositif SkyTEM a permis de cartographier l’anomalie du champ magnétique et la résistivité électrique du sous-sol jusqu’à 300 m de profondeur, et ce, sur l’ensemble de l’île. L’acquisition de ce jeu de données met en évidence la problématique de l’interprétation des données électromagnétiques héliportées à l’échelle régionale. L’interprétation d’un modèle 3D de résistivité d’une superficie 2 500 km2 nécessite la mise en place de méthodologies innovantes pour le confronter aux données géologiques, climatiques et hydrogéologiques. L’objectif de la thèse est de valoriser ce jeu de données géophysique à l’échelle régionale en intégrant l’analyse hydrogéologique à différentes échelles spatiales. Pour répondre à ces problématiques, cette thèse s’organise autour d’une méthodologie hydrogéophysique multi-échelle qui permet d’étudier la répartition et le fonctionnement des aquifères à des échelles inédites jusqu’alors. Pour interpréter les 350 000 sondages électromagnétiques de la campagne, une approche statistique a été développée pour synthétiser une information sur les contrastes 3D en 2D. Les résultats, cohérents avec les connaissances géologiques et hydrogéologiques de l’île, ont permis d’analyser l’impact des paramètres géologiques et climatiques régionaux sur la répartition des aquifères et les processus d’altération. Sur le littoral, les données de résistivité sont confrontées à des logs de conductivité électrique de l’eau souterraine afin de valider l’interprétation de la géophysique. Le modèle de résistivité permet ainsi de cartographier et d’analyser les paramètres de contrôle du phénomène d’intrusion saline à l’échelle de l’île. En altitude, l’utilisation conjointe des données électromagnétiques et magnétiques héliportées permet de caractériser la géométrie des structures géologiques et d’imager les profils et paléo-profils d’altération météorique. / In 2014, Reunion Island was covered by a vast airborne geophysics campaign. The SkyTEM device mapped magnetic anomalies and bulk resistivity at an extra 300 m depth throughout the island. The resulting dataset revealed the issue of interpreting airborne electromagnetic data at the regional scale. The interpretation of a 3D resistivity model wrapping 2 500 km2 requires the implementation of innovative methodologies to compare it with geological, climatic and hydrogeological data. The aim of the thesis is to enhance this geophysical dataset at the regional scale by integrating hydrogeological analysis at different spatial scales. To answer these issues, this thesis revolves around a multi-scale hydrogeophysical methodology, which allows to analyze how aquifers are distributed and their behaviors on unprecedented scales. A statistical approach has been developed to synthesize 3D geo-electrical contrasts in 2D to interpret the 350 000 soundings. All outcomes are consistent with the geological and hydrogeological knowledge of the island, enabling us to study how regional geological and climatic parameters impact the distribution of aquifers and weathering processes. In the coastal zone, resistivity data are compared with groundwater electrical conductivity logs to validate the interpretation of geophysics. Thus, the resistivity model helped mapping saltwater intrusion and analyzing its control parameters at the island scale. Inland, the combined use of airborne electromagnetic and magnetic data made it possible to characterize the geometry of geological structures and to image weathering profiles and paleo-profiles. Combining results gathered on various scales allows the analysis of weathering impact on aquifers of shield volcanoes. On the coastal zone, un-weathered and highly permeable lithological units (up to 10-1 m/s) are subject to saltwater intrusion, even with recharge rates up to 6 to 8 m per year. With decreasing transmissivity, aquifers become less exposed to saltwater intrusion. According to geophysics outcomes, the contacts between different eruptive phase products at high altitude are characterized by specific weathering paleo-profiles which create permeability contrasts conducive to perched aquifers establishment. Examining the geophysical response in different areas of the island made it possible to analyze the dynamics of weathering processes, initially controlled by the age of the formations and secondly, by the rainfall rates and the temperature. These results showed that weathering and structure of basaltic volcanoes depend on their age and on windward/leeward slopes. Thus, our research helped improve the accuracy of the conceptual hydrogeological model including geological structuring and time evolution of basaltic volcanic aquifers in an insular environment.
19

Saltvatteninträngning i bergborrade brunnar : En undersökning på Tynningö i Stockholms skärgård / Saltwater intrusion in drilled wells : A study on the island Tynningö in the Stockholm archipelago

Söderholm, Malin January 2015 (has links)
Groundwater is often the most important source of drinking water. In recent decades, the environmental threats to this resource have increased dramatically, because of pollution, over usage and disturbed water balances. Climate change will affect the groundwater in coastal areas by sea-level rise and changes in precipitation and temperature. If seasonal variations in groundwater recharge and groundwater reservoirs changes it could lead to problems for drinking water supplies.  In coastal areas and archipelagos, there is a general lack of groundwater because of thin soil covers and limited storage capacities within the bedrock aquifers. When water abstraction in a well is too large in relation to the formation of groundwater the area can be affected by saltwater intrusion. More people are settling permanently in former summer-house areas, which mean higher pressure on groundwater as a drinking water resource. This development is under way on the island Tynningö in the Stockholm archipelago. Saltwater intrusion in wells has been investigated in collaboration with Södra Roslagens Miljö- och Hälsoskyddskontor (SRMH). The aim was to find out how many of the wells that have enhanced chloride concentrations (≥50 mg/l) and how different parameters affect the concentrations. The study is limited to houses where people live permanently. Water samples from 67 wells have been analyzed for chloride concentrations. Parameters that may affect the risk of saltwater intrusion, for example how deep the well is and its distance to the shoreline, are used to interpret the measured chloride concentrations. A comparison with previous chloride measurements is also made to evaluate how the problem has changed over time. Furthermore, measures to reduce water consumption and possibilities for the municipality to prevent problems with saltwater intrusion are discussed. The results show that 24 % of the wells have an enhanced chloride concentration (≥50 mg/l), which is in harmony with results from earlier studies in Tynningö and similar areas. This survey was conducted during winter; chloride concentrations in summer may therefore be higher. The result shows that all the investigated parameters have an influence on the chloride concentrations. Wells with enhanced chloride concentrations are slightly deeper, older, lower in the terrain, closer to the shoreline and the well bottom is located deeper below sea level. The number of people using the well also affects the risk of saltwater intrusion. / Grundvatten utgör ofta den viktigaste källan till dricksvatten. De senaste årtiondena har miljöhoten mot denna resurs ökat kraftigt till följd av föroreningar, överutnyttjande och rubbad vattenbalans. Klimatförändringarna kommer att påverka grundvattnet i kustområden genom havsnivåhöjning och förändrad nederbörd och temperatur. Om grundvattenbildningen och grundvattenmagasinens årstidsvariationer förändras kan det leda till problem för den enskilda dricksvattenförsörjningen. I kust- och skärgårdsområden råder det i allmänhet brist på grundvatten på grund av tunna jordtäcken och små lagringsmöjligheter i berggrunden. När vattenuttaget i en brunn blir för stort i förhållande till nybildningen av grundvatten kan området drabbas av saltvatteninträngning. I många tidigare fritidshusområden bosätter sig fler permanent, vilket innebär ett större tryck på grundvattnet. På Tynningö i Stockholms skärgård pågår en sådan utveckling och saltvatteninträngning i enskilda brunnar har därför undersökts i samarbete med Södra Roslagens Miljö- och Hälsoskyddskontor (SRMH). Syftet har varit att ta reda på hur många av brunnarna som har förhöjda kloridhalter (≥50 mg/l) samt hur olika parametrar påverkar kloridhalten. Undersökningen är avgränsad till permanentboenden och vattenprover från 67 brunnar har analyserats för klorid. Parametrar som kan påverka risken för saltvatteninträngning, t.ex. brunnens djup och dess avstånd till strandlinjen, har sedan använts för att analysera de uppmätta kloridhalterna. En jämförelse med tidigare kloridmätningar har även gjorts för att utvärdera hur problemet har förändrats över tid. Vidare har åtgärder för att minska vattenförbrukningen samt kommunens möjligheter att förebygga problem med saltvatteninträngning diskuterats. Resultatet visar att 24 % av brunnarna har en förhöjd kloridhalt (≥50 mg/l), vilket stämmer överrens med resultat från tidigare undersökningar på Tynningö och i liknande områden. Denna undersökning genomfördes under vintern. Eftersom kloridhalten påverkas av årstid kan kloridhalterna sommartid komma att bli högre. Resultatet visar att samtliga undersökta parametrar har en påverkan på kloridhalten. Brunnar med förhöjda kloridhalter är något djupare, äldre, ligger lägre i terrängen och närmare stranden och brunnsbottens nivå ligger djupare under havsnivån. Även antal personer som använder brunnen påverkar risken för saltvatteninträngning.
20

The Causeway: Bridging Disaster Relief, Recovery, and Climate Adaptation in the Anton Ruiz Watershed

Schiavoni, Alexandra Elizabeth 10 July 2019 (has links)
The impact of natural disasters is often exacerbated by a disparity between resources for relief and recovery. When the barrio of Punta Santiago in Puerto Rico was devastated by Hurricane Maria in September of 2017, many of its residents lived in the remains of their homes for over a year while they rebuilt from wind damage and flood waters that rose over 6 feet. As climate change leads to an even more constrained timeline for response with increasingly frequent and intense storms, the future of Punta Santiago and other coastal communities worldwide will necessitate strategies ranging from nature-based shore protection systems, coastal setbacks, and managed retreat. This thesis investigates the time disparate processes of disaster relief, recovery, and climate adaptation through the lens of their impact upon the interdependent identities of people and place as informed by theorists and designers including J.B. Jackson and Patrick Geddes. My approach works from the scale of the Antón Ruíz watershed to the delta to uncover the historical and contemporary processes that knit people in the region to the land. I identify commonalities in the immediate recovery needs and long-term resiliency of the community and ecosystems, and seek to support ongoing globally significant research of the rare coastal systems surrounding Punta Santiago. The proposed design, a causeway linking the coast to the hills, dovetails disaster relief and recovery with climate adaptation by providing a persistent connection that restores and reveals the dynamic coastal landscape. / Master of Landscape Architecture / Global warming is correlated with an increase in sea level rise, atmospheric moisture (water content in the air), and surface sea temperatures. The body of research around the complex interaction of these factors is growing, but current projections are that warmer seas will cause more intense hurricanes. Coastal communities, particularly those with fewer economic resources, bear the brunt of this trend and recovery is more difficult with each passing storm. After Hurricane Maria struck in September 2017, many residents of the barrio of Punta Santiago in Puerto Rico lived in the remains of their homes for over a year with little resources to rebuild from the severe wind damage and flood waters that rose over 6 feet. Recovery is still underway almost two years later. A sustainable way forward for Punta Santiago and other coastal communities worldwide necessitates strategies ranging from natural shore stabilization techniques like mangrove buffers and living reefs to restrictions on coastal development, and even the relocation of communities. This thesis investigates the time disparate processes of disaster relief, recovery, and climate adaptation through the lens of their impact upon the interdependent identities of people and place as informed by theorists and designers including J.B. Jackson and Patrick Geddes. My approach works from the scale of the Antón Ruíz watershed to the delta to uncover the historical and contemporary land use that knit people in the region to the land. I identify commonalities in the immediate recovery needs and long-term resiliency of the community and ecosystems, and seek to support ongoing globally significant research of the rare coastal systems surrounding Punta Santiago. The proposed design, a causeway linking the coast to the hills, dovetails disaster relief and recovery with climate adaptation by providing a persistent connection that restores and reveals the dynamic coastal landscape.

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