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The use of water resources has increased with rapid population growth, industrial development, and agricultural activities. Besides, the problem might increase with the potential climate change impacts on water quantity. Thus, sustainable use of water resources becomes crucial. Modeling studies provide scientific support to the analysis of water resource problems and develop strategies for current and potential problems for the sustainable management of water resources. In this study, WEAP-PGM (Water Evaluation and Planning System—Plant Growth Model) was applied to the Sakarya River Basin in Turkey, where almost 50% of the area is agricultural land. The main goals in the study are compiling/integrating available data from different sources in a data-scarce region for hydrological models, and estimating the water budget components of Sakarya River Basin on an annual basis as well as investigating the applicability of WEAP-PGM. General model performance ratings indicated that model simulations represent streamflow variations at acceptable levels. Model results revealed that, runoff is 4747 million m3, flow to groundwater is 3065 million m3 and evapotranspiration is 23,011 million m3. This model setup can be used as a baseline for calculating the crop yields under climate change in the context of water-food-energy nexus in the further studies.
Salim Yaykiran; Gokhan Cuceloglu; Alpaslan Ekdal. Estimation of Water Budget Components of the Sakarya River Basin by Using the WEAP-PGM Model. Water 2019, 11, 271 .
AMA StyleSalim Yaykiran, Gokhan Cuceloglu, Alpaslan Ekdal. Estimation of Water Budget Components of the Sakarya River Basin by Using the WEAP-PGM Model. Water. 2019; 11 (2):271.
Chicago/Turabian StyleSalim Yaykiran; Gokhan Cuceloglu; Alpaslan Ekdal. 2019. "Estimation of Water Budget Components of the Sakarya River Basin by Using the WEAP-PGM Model." Water 11, no. 2: 271.
The Dalyan Region that drains into a complex lagoon system is located on the Mediterranean Sea coast of southwest Turkey. There are no large streams in the area, indicating that a considerable amount of freshwater draining into the lagoon is expected to be based on groundwater inflows and that groundwater quality is an important issue for the lagoon ecosystem. Since the lagoon and its watershed are within an environmental special protection area, planning preventive and mitigative measures toward water quantity and quality, including groundwater, is crucial. Since an important step in such a study is the generation of vulnerability map of groundwater pollution, this study aims at the generation of an intrinsic groundwater vulnerability map and its assessment for the first time in the study area based on the DRASTIC method. Since the DRASTIC method requires recharge rates for the calculation of groundwater pollution potential index, these were obtained from a previous modeling study conducted in the same area, where SWAT model was used. The intrinsic vulnerability maps generated were overlaid with current land-use maps to evaluate actual groundwater pollution risk. Our analyses showed that 46% of the study area is under the high risk of groundwater pollution, where 62% of the vulnerable high-risk area is agricultural land.
Ali Ertürk; Alpaslan Ekdal; Melike Gurel; Nusret Karakaya; Gokhan Cuceloglu; Ethem Gönenç. Model-based assessment of groundwater vulnerability for the Dalyan Region of southwestern Mediterranean Turkey. Regional Environmental Change 2017, 17, 1193 -1203.
AMA StyleAli Ertürk, Alpaslan Ekdal, Melike Gurel, Nusret Karakaya, Gokhan Cuceloglu, Ethem Gönenç. Model-based assessment of groundwater vulnerability for the Dalyan Region of southwestern Mediterranean Turkey. Regional Environmental Change. 2017; 17 (4):1193-1203.
Chicago/Turabian StyleAli Ertürk; Alpaslan Ekdal; Melike Gurel; Nusret Karakaya; Gokhan Cuceloglu; Ethem Gönenç. 2017. "Model-based assessment of groundwater vulnerability for the Dalyan Region of southwestern Mediterranean Turkey." Regional Environmental Change 17, no. 4: 1193-1203.
Lagoons are important ecosystems occupying large coastal areas worldwide. Lagoons contain various mixtures of marine and freshwater sources which are highly dynamic in time. However, it often remains a challenge to identify and quantify dynamic changes of water sources, particularly in heterogeneous lagoon systems like the Köycegiz–Dalyan lagoon (KDL), which is located at the south-west of Turkey on the Mediterranean Sea coast. The objective of this study was to quantify different contributions of potential water sources i.e. surface water, groundwater and seawater in the lagoon and how these water sources changed over time and space. In the wet- and dry-season stable isotopes of water, chloride concentration (Cl-) and salinity were measured in two depths in the lagoon and surrounding water bodies (sea, lake, groundwater). Different components of water sources were quantified with a three component endmember mixing analysis. Differences in Cl- and stable isotopes over time indicated the dynamic behaviour of the system. Generally, none of the groundwater samples was impacted by water of the Mediterranean Sea. During the wet season, most of the lagoon water (> 95%) was influenced by freshwater and vertically well mixed. During the dry season, high Cl- in the deeper sampling locations indicated a high contribution of marine water throughout the entire lagoon system due to saltwater intrusion. However, a distinct layering in the lagoon was obvious from low Cl- and depleted isotope contents close to the surface supporting freshwater inflow into the system even during the dry season. Besides temporal dynamics also spatial heterogeneities were identified. Changes in water sources were most evident in the main lagoon channel compared to more isolate lagoon lakes, which were influenced by marine water even in the wet season, and compared to side branches indicating slower turnover times. We found that environmental tracers helped to quantify highly dynamic and heterogeneous contributions of different water sources in the Köycegiz–Dalyan lagoon.
C. Stumpp; A. Ekdal; I. E. Gönenc; P. Maloszewski. Hydrological dynamics of water sources in a Mediterranean lagoon. Hydrology and Earth System Sciences 2014, 18, 4825 -4837.
AMA StyleC. Stumpp, A. Ekdal, I. E. Gönenc, P. Maloszewski. Hydrological dynamics of water sources in a Mediterranean lagoon. Hydrology and Earth System Sciences. 2014; 18 (12):4825-4837.
Chicago/Turabian StyleC. Stumpp; A. Ekdal; I. E. Gönenc; P. Maloszewski. 2014. "Hydrological dynamics of water sources in a Mediterranean lagoon." Hydrology and Earth System Sciences 18, no. 12: 4825-4837.
Western Mediterranean Region of Turkey is subject to considerable impacts of climate change that may adversely affect the water resources. Decrease in annual precipitation and winter precipitation as well as increase in temperatures are observed since 1960s. In this study, the impact of climate change on groundwater resources in part of Köyceğiz-Dalyan Watershed was evaluated. Evaluation was done by quantifying the impacts of climate change on the water budget components. Hydrological modeling was conducted with SWAT model which was calibrated and validated successfully. Climate change and land use scenarios were used to calculate the present and future climate change impacts on water budgets. According to the simulation results, almost all water budget components have decreased. SWAT was able to allocate less irrigation water because of the decrease of overall water due to the climate change. This resulted in an increase of water stressed days and temperature stressed days whereas crop yields have decreased according to the simulation results. The results indicated that lack of water is expected to be a problem in the future. In this manner, investigations on switching to more efficient irrigation methods and to crops with less water consumption are recommended as adaptation measures to climate change impacts.
Ali Ertürk; Alpaslan Ekdal; Melike Gürel; Nusret Karakaya; Cigdem Guzel; Ethem Gönenç. Evaluating the impact of climate change on groundwater resources in a small Mediterranean watershed. Science of The Total Environment 2014, 499, 437 -447.
AMA StyleAli Ertürk, Alpaslan Ekdal, Melike Gürel, Nusret Karakaya, Cigdem Guzel, Ethem Gönenç. Evaluating the impact of climate change on groundwater resources in a small Mediterranean watershed. Science of The Total Environment. 2014; 499 ():437-447.
Chicago/Turabian StyleAli Ertürk; Alpaslan Ekdal; Melike Gürel; Nusret Karakaya; Cigdem Guzel; Ethem Gönenç. 2014. "Evaluating the impact of climate change on groundwater resources in a small Mediterranean watershed." Science of The Total Environment 499, no. : 437-447.
Lagoons are important ecosystems occupying large coastal areas worldwide. Lagoons contain various mixtures of marine and freshwater sources which are highly dynamic in time. However, it often remains a challenge to identify and quantify dynamic changes of water sources, particularly in heterogeneous lagoon systems like the Köycegiz-Dalyan Lagoon (KDL), which is located at the southwest of Turkey on the Mediterranean Sea coast. The objective of this study was to quantify different contributions of potential water sources i.e. surface water, groundwater and seawater in the lagoon and how these water sources changed over time and space. In the wet and dry season stable isotopes of water, chloride concentration (Cl-) and salinity were measured in two depths in the lagoon and surrounding water bodies (sea, lake, groundwater). Different components of water sources were quantified with a three component endmember mixing analysis. Differences in Cl- and stable isotopes over time indicated the dynamic behaviour of the system. Generally, none of the groundwater samples was impacted by water of the Mediterranean Sea. During the wet season, most of the lagoon water (>95%) was influenced by freshwater and vertically well mixed. During the dry season, high Cl- in the deeper sampling locations indicated a high contribution of marine water throughout the entire lagoon system due to salt water intrusion. However, a distinct layering in the lagoon was obvious from low Cl- and depleted isotope contents close to the surface supporting freshwater inflow into the system even during the dry season. Besides temporal dynamics also spatial heterogeneities were identified. Changes in water sources were most evident in the main lagoon channel compared to more isolate lagoon lakes, which were influenced by marine water even in the wet season, and compared to side branches indicating slower turnover times. We found that environmental tracers helped to quantify contributions of different water sources in the Köycegiz-Dalyan Lagoon which is a highly dynamic and heterogeneous groundwater dependent ecosystem.
C. Stumpp; A. Ekdal; I. E. Gönenc; P. Maloszewski. Hydrological dynamics of water sources in a Mediterranean lagoon. Hydrology and Earth System Sciences Discussions 2014, 1 .
AMA StyleC. Stumpp, A. Ekdal, I. E. Gönenc, P. Maloszewski. Hydrological dynamics of water sources in a Mediterranean lagoon. Hydrology and Earth System Sciences Discussions. 2014; ():1.
Chicago/Turabian StyleC. Stumpp; A. Ekdal; I. E. Gönenc; P. Maloszewski. 2014. "Hydrological dynamics of water sources in a Mediterranean lagoon." Hydrology and Earth System Sciences Discussions , no. : 1.
This study evaluated the kinetics of nonylphenol ethoxylate (NPEO) and acetate biodegradation at a moderate sludge age by acclimated culture under aerobic conditions. A laboratory-scale sequencing batch reactor was set and fed only with acetate mixture. The system was operated at steady state with a sludge age of 8 days. Following this stage, a mixture of NPEO and acetate was fed to the mixed culture in order to assess the biodegradation kinetics of NPEO and its impact on acetate utilization. A mechanistic model was developed involving model components and kinetic parameters for both substrates. The model was calibrated with parameters such as oxygen uptake rate and polyhydroxyalkanoates. Biodegradation characteristics and kinetics of acetate and NPEO were estimated by using the model results. Evaluation of calibrated model indicated that exposure of NPEO to non-acclimated sludge caused significant inhibitory impact on the utilization and storage of acetate. However, acclimation ofbiomass greatly suppressed inhibitory effects of NPEO on growth process involved in the degradation of acetate.
Alpaslan Ekdal. Fate of nonylphenol ethoxylate (NPEO) and its inhibitory impact on the biodegradation of acetate under aerobic conditions. Environmental Technology 2013, 35, 741 -748.
AMA StyleAlpaslan Ekdal. Fate of nonylphenol ethoxylate (NPEO) and its inhibitory impact on the biodegradation of acetate under aerobic conditions. Environmental Technology. 2013; 35 (6):741-748.
Chicago/Turabian StyleAlpaslan Ekdal. 2013. "Fate of nonylphenol ethoxylate (NPEO) and its inhibitory impact on the biodegradation of acetate under aerobic conditions." Environmental Technology 35, no. 6: 741-748.