Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Conservation Strategies Against Climate Change Effects on Coastal Historic Settlements: the Case of Kuşadasi Citadel(01. Izmir Institute of Technology, 2023) Çıkıkçı, Süleyman Burçak; Yüceer, Hülya; Baba, AlperClimate change is currently one of the most essential and fastest-growing threats to people and their heritage around the world. Heritage assets and sites are vulnerable to the impacts of climate change due to their age and being in constant interaction with the environment and weathering processes. In particular, historic coastal settlements are highly vulnerable to climate change effects due to their proximity to the sea, which may lead to coastal erosion, changing sea levels, abrupt changes in air temperatures, storms and floods that may damage or even lead to the disappearance of these areas. Thus, developing resilience through tailor-made conservation strategies for historic coastal settlements is crucial to transfer them to future generations. In this context, this study discusses the effects of climate change through the example of Kuşadası Citadel, a historical coastal settlement located in the Mediterranean Basin, which is expected to be highly vulnerable to climate change. The study identified the potential conservation problems that may arise from the effects of climate change on the listed and 'façade to be conserved' immovable cultural assets of the Kuşadası Citadel. Accordingly, the study has developed its method. Area-specific climate change impacts were determined, vulnerability and risk analyses were performed, and administrative, site and building-scale conservation strategies were developed. In conclusion, strategies have been developed for the Kuşadası Citadel, which is highly vulnerable to the effects of climate change, to protect it from these effects at different scales. It is an example of coastal settlement research in the context of climate change adaptation and gives guidance for local-scale conservation efforts.Master Thesis Kinetics of Silica Polymerization at Various Conditions(01. Izmir Institute of Technology, 2022) Hasköylü Toker, Öykü Çağ; Demir, Mustafa Muammer; Baba, AlperSilica is the most abundant element on Earth because the Earth's crust is composed mainly of metal silicates. The source of this silica is mainly volcanic rocks, which come to the surface through tectonic activity and are the primary source of heat for geothermal activity. The silica concentration in a geothermal fluid is higher than the solubility limit of natural waters, so scaling of (metal) silicates is often observed in geothermal operations. This situation has become critical for geothermal power plants. Since silicates have an insulating structure, they lead to a reduction in energy efficiency during fluid transport. The formation of silica-rich deposits should be understood to minimize the negative effects of the scaling. Briefly, silicic acid molecules in the reservoir system are condensed, and the monomeric silicic acid molecules bind to each other via covalent bonds. In the course of this reaction, dimers, tetramers and short oligomers are formed, and eventually a large polymeric silica network is formed. In the presence of metals, both the kinetics of polymerization and the structure of the network are inevitably affected. In this study, the presence of kinetic parameters (different salts such as FeCl3, MgCl2, AlCl3 and NaCl), the reaction process, the rate and the activation energy of silica polymerization at different temperatures between 25 and 90 °C were investigated. The yellow silicomolybdate method was used to determine the concentration of monomeric silica. The order of the polymerization reaction was given as 3. The polymerization occurs in the initial phase, in the first 40 minutes, where the activation energy was about 29.52 ± 2.28 kJ/mol and the rate constant was of the order of 4x10-8 mol-2∙L2∙s-1. The results also confirmed that pH has a stronger effect on the kinetics of silica polymerization than temperature. The neutral solution decreases rapidly, while the acidic solution has an induction phase in the first hour of polymerization. Different temperatures did not affect the polymerization rate as much as pH. At 25°C the experiment showed the fastest polymerization, but at 90°C the low concentration changed from the beginning. During all these experiments, no scaling of amorphous silica was observed, only the polymerization of silica.Master Thesis Impact of Urbanization on Hydrogeodynamic Systems: a Case Study: Bornova Region (i̇zmir, Turkey)(01. Izmir Institute of Technology, 2021) Öztürk, Bahadır; Baba, Alper; İşbuğa, VolkanUrbanization is one of the most critical processes affecting land and water use. Understanding urbanization and its impact on ground systems gained prominence with global climate change and population increase. This study focuses on the new city center Bornova Plain, İzmir; Turkey, used as agricultural land until the 1950s. Later, the region was opened for settlement, and excessive urbanization decreased the hydraulic conductivity of the surface area of the plain with the constructed buildings, road pavements, and other surface coverings. Effects of the land use- land cover changes on the hydrodynamic system of Bornova Plain's aquifers were investigated in three parts. Firstly, GIS-based hydrological models with two different periods (2004 and 2020) scenarios were developed with ArcSWAT for this thesis. Using SWAT models, elements of the water budget equation were determined. With SWAT Models, Recharge/Precipitation, Streamflow/Precipitation, and Baseflow/Total flow ratios were found to decrease 52%, 26.09%, and 11.86%, respectively, and Surface Runoff/Total Flow, and ET/Precipitation ratios were found to increase 20.59%, and 15.09% with urbanization increment comparing 2004 and 2020. Secondly, soil's bearing capacity changes with groundwater level changes within a year were investigated using five observation wells. Conceptual models were created for each well. Maximum of 14.82% of bearing capacity change was observed in the wells. Thirdly, PLAXIS 3D models were created to understand the effect of the groundwater level changes on pile settlements for sandy and clayey soils in the region. Conceptual models created and maximum of 12.74% settlement difference was observed for different groundwater levels.Master Thesis Surface Water Quality Modeling for Best Management Practices - a Case Study From Bakırçay River Basin(01. Izmir Institute of Technology, 2021) Kazancı, Yiğithan; Gündüz, Orhan; Kazancı, Yiğithan; Baba, Alper; Baba, Alper; Gündüz, OrhanThis study was carried out to analyze the water quality in the Bakırçay River basin, which is known to be exposed to intense industrial and agricultural pollutant loads. A mathematical model system called AQUATOOL was used to reveal the changes that the effects of anthropogenic and natural events in the basin will cause on the conservative water quality parameters and nutrients. Model results are given in wet (April) and dry (September) periods for 4 points determined from upstream to downstream in the basin on a spatial basis, and temporal evaluation is also given for 1 upstream river water body, 1 downstream river water body, and 1 lake water body. Seven best management practices scenarios were determined and implemented one after the other in the model. Spatially, the results reveal good water status for both the dry period and the wet period at the upstream points, while at the downstream points, all parameters except BOD5 and Dissolved Oxygen are found to be in poor condition. Besides, similar situations arise in spatial-based results, and despite the scenarios, parameters could not reach good water status except for the lake waterbodies. The improvement in lake results occurs due to dilution, not scenarios. With this study, the pollution load in Bakırçay River Basin and the effects it creates once again revealed that if the anthropogenic loads are not reduced, the water quality of the basin will reach irreversible points for many years. It is thought that this study can constitute a source document for decision-makers, especially in terms of efficiency comparisons in the best management scenarios to be applied.Master Thesis Development of a New Antiscalant for Minimization of Stibnite Scaling in Geothermal Binary Plants(01. Izmir Institute of Technology, 2021) Karaburun, Emre Mustafa; Baba, Alper; Demir, Mustafa Muammer; Demir, Mustafa Muammer; Baba, AlperDemand for renewable and sustainable energy resources has been increasing in recent years due to the adverse effects of fossil energy resources (gases, oil, coal ect,) on human health and nature. Since geology properties of our country is rich in geothermal energy resources, there is a remarkable increase in plant capacities every year. Geothermal energy is the energy obtained from the fluid, gas, and steam that have been stored in reservoirs by carrying the heat energy accumulated in the rocks in the depths of the earth or surfaced along the discontinuity zones.The increase in the use of geothermal energy and the increase in the capacity of the power plants has also revealed the problem of scaling. The main cause of deposition are the decrease in solubility of minerals by a decrease in pressure and temperature upon pumping the geothermal brine up to the ground. Calcium carbonate, calcium sulphate, metal silicates (Mg, Fe) are the most widely accepted types of scaling. In recent years, antimony and arsenic sulfide scaling have been encountered in volcanic and metamorphic regions. Between these two types of scaling, antimony sulfide is mostly seen in the heat-exchangers and preheaters where the temperature drops suddenly. In this thesis, the antimony sulfide scaling formed in the geothermal power plant was synthesized in an autoclave reactor under specified conditions. Water-soluble polymers nominee for being antiscalants such as Poly (vinyl sulfonic acid), Poly (acrylamide-co-vinyl sulfonic acid), Poly (acrylamide-co-vinyl phosphonic acid), Alginic Acid, Natural antiscalants, Polyacrylic acid, and Polyvinyl alcohol were employed. The results suggest that polymers containing vinyl sulfonic acid and acrylamide likely shows remarkable progress in increasing the concentration of ions in decantate, particularly at low dosages. (≈5 ppm)Master Thesis Hec Hms Hydrological Model Application Using Scs Curve Number and Soil Moisture Accounting: Case Study of Alaşehir Basin(Izmir Institute of Technology, 2019) Akdeğirmen, Özgün; Baba, Alper; Tayfur, GökmenWater is known as source of life throughout mankind’s history. According to first records of written history; Sumerians and Akkadians used water for their inland transportation and irrigation systems. With first settlements, mankind’s dependency to water has been increased and became one of the most substantial natural resource in our modern age. Importance of this resource even more solidifies when we consider its property of being limited. With realization of global climate change in early 19th century; treat to this limited resource has been revealed. Approximately 68% of the freshwater on earth reserved in glaciers and icecaps and 30% is reserved in groundwater systems according to United States Geological Survey’s (USGS) studies. Owing to the quantity and less compromised to contaminants nature, majority of our freshwater needs met from groundwater. Although the importance of groundwater, its management have always been a challenge due to hard to quantify volumetric changings in aquifers. This study focused on creating a hydrological basin model to investigate volumetric recharge changings in groundwater system. Under scope of this study in an attempt to acquire groundwater recharge amounts; practicality of HEC-HMS hydrological modeling software has been investigated. A SCS Curve Number and Soil Moisture Accounting (SMA) loss methods has been chosen for HEC-HMS modeling application due to availability and accessibility of data that required for loss methods. After data collection from meteorological stations, core drill samples; both methods have been used in HEC-HMS simulation environment and their predictions have been compared. In the comparisons, it was determined that the SCS Curve Number method predicts higher flow potentials and groundwater infiltration amounts compared to the SMA method. Models foresee an average of 33.4 % of precipitation infiltrates into groundwater system.Master Thesis Natural Groundwater Recharge in the Alaşehir Sub-Basin (gediz Basin, Turkey)(Izmir Institute of Technology, 2018) Tonkul, Serhat; Baba, Alper; Şimşek, CelalettinThe increase in water utilization due to climate change in recent years, as well as excessively growing population causes to an increase in usage of groundwater and threatens water resources. Dams and artificial lakes are being constructed to ensure the sustainability of water resources, but there is much evaporation on large surface of these structures. Due to reason that the evaporation losses are not experienced, the groundwater recharge by direct rainfall becomes important. Groundwater recharge protects the water without too much evaporation in the basins and increases the potential of water resources and ensures sustainability. The aim of this study is to determine alluvial aquifer recharge in Alaşehir (Manisa) sub-basin using numerical and chemical methods. In addition to this aim, the mechanism of mixing of groundwater and geothermal fluid has also been examined. The Gediz Basin, located in the west of Turkey constitutes 2% of the country, has an important groundwater potential in the area where it is used. The Alasehir sub-basin, located in the southeast of the Gediz Basin and having extensive withdrawal for irrigation, constitutes the study area. Alluvial aquifer is the main groundwater bearing lithological unit in the plain. Twenty-five research wells, which is ranging from 20 m to 50 m in depth, were opened for the calculation of the recharge of the aquifer. Soil characterization was done on the core samples and the aquifer characterization was performed and the alluvial aquifer recharge was calculated. As a result, the recharge value of annual precipitation is range from 21.78 mm to 68.52 mm and average recharge from precipitation is 43.09 mm in the wells which are opened into the alluvium aquifer. According to the numerical model, this amount of recharge corresponds to 10% of the amount of annual rainfall. This estimated recharge ratio directly represents recharge from precipitation into the aquifer. According to the results of the chemical method, it is understood that the average recharge value from precipitation is 16.38%. In addition, the mixing ratio of the groundwater and geothermal fluid is 17% in the sub-basin. Keywords Aquifer Characterization, Alaşehir, Precipitation Recharge, Numerical ModellingMaster Thesis The Investigation of Seawater Intrusion of Coastal Aquifer in Karareis (karaburun Peninsula)(Izmir Institute of Technology, 2016) Mansour, Ahmed Y. S.; Baba, Alper; Gündüz, OrhanSeawater intrusion is a major problem to freshwater resources especially in coastal areas where fresh groundwater is surrounded and could easily be influenced by seawater. This study presents the development of conceptual and numerical model for the coastal aquifer of Karareis region in the western part of Turkey. The study also presents the interpretation and the analysis of the groundwater levels recorded by groundwater data loggers. Groundwater pumping from Karareis aquifer has increased significantly during the summer period to meet the agriculture and domestic water demands. Levels of groundwater were measured at nine locations in Karareis region; also water samples were collected and analyzed for some parameters. For this study SEAWAT code is used to solve the numerical model for the coupled density dependent flow system. The model was calibrated using the average of one-year dataset of collected groundwater levels. Model validation was handled using the average of groundwater levels measured over more one year. Five scenarios were tested to understand the effects of pumping and climate change on groundwater levels and seawater intrusion in the next ten years. The result of analysis demonstrated a high concentration of electrical conductivity and chloride along the coastal part of the study area. As a result of the numerical model, seawater intrusion will extent about 420 m towards the land in the next ten years of increased pumping scenario, while a little change in water level and TDS concentration was recognized in climate change scenario. Results also showed that reducing the pumping from Karareis wells will be necessary to protect the freshwater from contamination by seawater.Master Thesis Effect of High Saline Geothermal Fluid on Soil and Surface Water: a Case Study From Tuzla, Çanakkale-Turkey(Izmir Institute of Technology, 2013) Katırcıoğlu, Gamze; Baba, AlperGeothermal energy can be defined as a heat from core of Earth and utilized for power generation, district heating and greenhouse. Use of geothermal energy has low environmental impact, particularly when compared with fossil fuels. However, geothermal fluid has some adverse effects for environment for instance contamination of surface water and soil. Examples of these effects occur in different parts of world. The objective of this study is to evaluate the effect of geothermal fluid particularly on surface water and soil in Tuzla Geothermal Field (TGF) where is located on Biga Peninsula, in the northwestern of Anatolia. TGF is 5 km far from Aegean Sea and 80 km south of Çanakkale. Geothermal fluid of TGF has high salinity (EC > 91 mS/cm) and high temperature (reservoir temperature is 173 °C). Water samples were taken from February 2012 to April 2013 to determine the physical and chemical (major anioncations and heavy metals) properties of the surface water quality. Furthermore, the soil samples analyzed for physical and chemical properties. All data were evaluated with ArcGIS 10.1 and Aquachem 4.0 software. The results showed that the levels of some major element such as Lityum (4-7 ppm), Barium (1-4 ppm) and Manganese (1-5 ppm) and some heavy metals such as Boron (> 13 ppm) and Strontium (> 14 ppm) in surface water, exceeded national and international limits. Boron and Strontium values of creek ranged from 13 to 27 ppm and from 14 to 154 ppm, respectively. Soil samples contain high concentration of Silisium (> 23800 mg/kg) and Aluminum (> 9000 mg/kg). Particularly, the uncontrolled discharge of geothermal fluid that is rich in terms of toxic elements into soil and surface water resources of the area influences other potential uses of these resources.