Evaluation of Climate Change Effect on Groundwater Resources in the Sahraye Bagh Plain, Lar

The analysis of climatic changes in the future and its impacts on groundwater resources is very important. This phenomenon, in areas where the vulnerability of the water sector is significant in the current situation, can cause considerable damages and provide a desertification setting in these areas. The trend of water table changes in Sahraye Bagh Plain,Larestan investigated by using the data from 17 observation wells during the 2006–2016 period. Using the non-parametric Mann-Kendall test indicated the prosence of a trend at the significance level of 99%. Derivation of the trend line slope using the Sen estimator showed that the groundwater level of the plain was receding 10.2 m during the period, on the average. As the agricultural sector is the main consumer of the groundwater resources in the plain, the water balancesituation was predicted using the Effective Rainfall (ER) method to assess the climate change impact on observation water table changes. The  ER index changes were evaluated by the outputs of the HadCM3 model. The results showed that the ER index in the A1B, A2 and B1 diffusion scenarios will increase by 73.2, 76.8 and 36.8%, respectively. This situation will further the current shortage of water in the Sahraye Bagh Plain and aggravateduring the 2080-2099 period. The increasing trend of groundwater extraction will enhance the drop in the groundwater level if the current withdrawal continues unchanged.