Effects of precipitation recharge and artificial discharge on salt water-fresh water interface movement in selçuk sub-basin: climatic indications

Download
2011
Aykanat, Gökben
Fluctuations in temperature and precipitation amounts due to climate change influence recharge rate of groundwater. Any variations in the amount of precipitation recharge and artificial discharge directly affect groundwater level and so the salt water intrusion rate in the aquifers, which are in contact with sea water. The purpose of this study is to determine the overall historical precipitation recharge trend in Selçuk sub-basin and to detect whether there is a decrease or increase in recharge amounts due to climate change since 1100 BC. Besides, it covers assessing the future position of the salt water-fresh groundwater interface as a result of possible fluctuations in climate and artificial discharge. For this purpose, numerical density dependent cross sectional groundwater flow with solute transport model was conducted using finite element approach. At first, current salt water-fresh water interface and artificial discharge related head changes in the aquifer were determined. Backward modeling was utilized to obtain concentration distribution in the year 1976 representing the last stage of the undisturbed period. Then, progradation of salt water-fresh water interface since 1100 BC to 1976 was modeled using calibrated parameters and current recharge value. As a result of sea-regression model simulations (1100 BC-1976) less degree of salt water intrusion than that of currently detected in the area was obtained. The result suggests that overall recharge amount in the last 3076 years must have been less than that of 1976. Moreover, future (2010-2099) position of the interface and head changes under the influence of both climate change and increasing water demand were determined. Future model simulations indicate that salt water-fresh water interface moves farther landward. However this movement is mostly due to increasing discharge amount rather than that of climatic changes.

Suggestions

Impacts of climate change on water resources on eastern mountainous region of Turkey
Güventürk, Abdülkadir; Yücel, İsmail; Department of Civil Engineering (2013)
Temperature and precipitation are the most important indicators of climate change. Especially for the basins fed by snow, the shifts of melting to earlier times, affects the streamflow. Increase in temperature causes to shifts of melting of snow to shift to earlier times so that hydrologic regime of the river system changes, and leads to changes in climatic conditions of the region. In this study the shifts of snow melting times are analyzed for the selected 15 streamflow stations located in Euphrates, Tigr...
Impact of alternating wet and dry periods on long-term seasonal phosphorus and nitrogen budgets of two shallow Mediterranean lakes
Coppens, Jan; ÖZEN, ARDA; Tavsanoglu, U. Nihan; Erdogan, Seyda; Levi, Eti E.; Yozgatlıgil, Ceylan; Jeppesen, Erik; Beklioğlu, Meryem (2016-09-01)
The water balance, with large seasonal and annual water level fluctuations, has a critical influence on the nitrogen and phosphorus dynamics of shallow lakes in the semi-arid climate zone. We constructed seasonal water and nutrient budgets for two connected shallow lakes, Lakes Mogan and Eymir, located in Central Anatolia, Turkey. The study period covered 20 years with alternations between dry and wet years as well as restoration efforts including sewage effluent diversion and biomanipulations in Lake Eymir...
Effects of trophic status, water level, and temperature on shallow lake metabolism and metabolic balance: A standardized pan-European mesocosm experiment
Scharfenberger, Ulrike; Jeppesen, Erik; Beklioğlu, Meryem; Sondergaard, Martin; Angeler, David G.; Cakiroglu, Ayse Idil; Drakare, Stina; Hejzlar, Josef; Mandy, Aldoushy; Papastergiadou, Eva; Sorf, Michal; Stefanidis, Konstantinos; Tuvikene, Arvo; Zingel, Priit; Adrian, Rita (Wiley, 2019-03-01)
Important drivers of gross primary production (GPP) and ecosystem respiration (ER) in lakes are temperature, nutrients, and light availability, which are predicted to be affected by climate change. Little is known about how these three factors jointly influence shallow lakes metabolism and metabolic status as net heterotrophic or autotrophic. We conducted a pan-European standardized mesocosm experiment covering a temperature gradient from Sweden to Greece to test the differential temperature sensitivity of ...
Impacts of climatic variables on water-level variations in two shallow Eastern Mediterranean lakes
Yagbasan, Ozlem; Yazıcıgil, Hasan; Demir, Vahdettin (2017-08-01)
Variations in temperature and precipitation have direct impacts on the physical, chemical and biological characteristics of the shallow lakes. This paper examines the possible linkages between climate variables and the water levels of shallow interconnected Lakes Mogan and Eymir, located 20 km south of Ankara in Central Anatolia. The variations in the lakes' water levels during 1996-2015 are studied and the impacts of climate variables on the lake levels are assessed to address the long-term consequences. T...
The importance of allochthonous organic matter quality when investigating pulse disturbance events in freshwater lakes: a mesocosm experiment
Caldero-Pascual, Maria; Yildiz, Dilvin; Yalçın, Gülce; Metin, Melisa; Yetim, Sinem; Fiorentin, Claudia; Andersen, Mikkel Rene; Jennings, Eleanor; Jeppesen, Erik; Ger, Kemal Ali; Beklioğlu, Meryem; McCarthy, Valerie (2021-11-01)
Extreme precipitation is occurring with greater frequency and intensity as a result of climate change. Such events boost the transport of allochthonous organic matter (allo-OM) to freshwater ecosystems, yet little is known about the impacts on dissolved organic matter (DOM) quality and seston elemental stoichiometry, especially for lakes in warm climates. A mesocosm experiment located in a Turkish freshwater lake was designed to simulate a pulse event leading to increased inputs of allo-OM by examining the ...
Citation Formats
G. Aykanat, “Effects of precipitation recharge and artificial discharge on salt water-fresh water interface movement in selçuk sub-basin: climatic indications,” M.S. - Master of Science, Middle East Technical University, 2011.