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 Selç / uk 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.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12613027/index.pdf |
| Date | 01 February 2011 |
| Creators | Aykanat, Gokben |
| Contributors | Camur, Zeki Mehmet |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for METU campus |
Page generated in 0.0018 seconds