Abstract
Considering the geographical location of Iran in the arid and semi-arid belt of the Earth and the low average annual precipitation, the groundwater resources, especially the karstic aquifers, are one of the most important water resources. The Golin karstic aquifer in the Alvand river basin of Kermanshah plays a vital role in supplying drinking and agricultural water to the surrounding local communities. The purpose of this study is to estimate the amount of water recharge into the Golin karstic aquifer in southwest of Kermanshah province. In this study, it is tried to consider the joints and fractures as an effective factor in karst aquifer recharge. For this purpose, the APLIS model is used with slope, lithology, soil, fractures and faults, geology, and altitude parameters in GIS environment. Using the APLIS model and taking into account the maximum weight for the related parameters, it was found that the recharge coefficient from precipitation into the related aquifer was calculated as 30%, while the water balance indicates the recharge level of about 50%. Studies show that the APLIS model ignores the role of joints and fissures which play an important role in the recharge of karstic aquifers. This study tries to consider the joints and fractures as an effective factor in recharge in the APLIS model and it was calibrated by applying some weights in the model based on the situation of the area. The results of this study show that the average water recharge to the karstic resources in this study area was 54.4% ranging from 18.8 to 90%, which corresponds with the water balance of the area