Determination of the origin and recharge process of water resources in Salda Lake Basin by using the environmental, tritium and radiocarbon isotopes (Burdur/Turkey)

Abstract

The Salda Lake basin which is in the southwestern Turkey is an important water body in view ofenvironmental values. We used stable isotopes (δD and δ18O), δ3H and 14C composition of the watersamples to understand recharge process effective in the groundwater and lake water. Water sampleswere collected in dry and wet periods and the stable isotope (δD and δ18O) and radiogenic isotope(14C) analysis were made in the basin. The δ18O contents of groundwater and lake water rangedfrom -9,94‰ to 1,18‰ in dry period and from -10,24‰ to 0,30‰, in wet period. δD contents ofgroundwater and lake water varied from -67,42‰ to 1,20‰ and from -64,51‰ to -2,80‰, in dryand period wet respectively. The stable isotope data of samples indicate a meteoric origin for allsamples. According to stable isotope data, groundwater samples seem to be recharged from higherelevations whereas the lake water is recharged from low elevations. The tritium (δ3H) content ofthe water samples ranges from 1.04 to 4.49 TU and from 1.91 to 4.18 TU in the dry period and wetperiod respectively. Long-term δ3H observations are required to determine whether these δ3H signalsare associated with young recharge or with the groundwater with long residence time. In addition,the 14C activities of the samples vary between 90 pmc and 110 pmc for Salda Lake waters and 530pmc and 5990 pmc for the groundwater.