This study investigates the impact of natural and anthropogenic factors on the physicochemical composition of groundwater in the Qazvin aquifer. Based on the optimized Gibbs diagram, the concentration of samples at the end of the freshwater interaction path with silicate units results from geochemical evolution due to the dissolution of these geological units and an increase in the Na/(Na+Ca) ratio. The ion exchange mechanism was assessed using bivariate diagrams of Ca+Mg vs. SO4+HCO3 and Schoeller's chloro-alkaline indices CAI-1 and CAI-2. The results indicate that in 68% of the samples, direct ion exchange, and in 32%, reverse ion exchange control the groundwater chemistry. The changes in Ca vs. SO4 indicate that gypsum dissolution alone is not the source of these ions. These changes could be due to ion mobility and transport during pedogenic processes (sulfur biogeochemical cycle) and anthropogenic factors. The study also examined the role of factors such as agricultural input, atmospheric input, soil nitrogen, sewage input, manure input, chemical fertilizers, and the denitrification process in groundwater pollution using NO3/Na vs. Cl/Na and the NO3/Cl vs. Cl diagrams. The results reveal that agricultural and sewage inputs significantly impact the NO3 and Cl content. Furthermore, in some locations, especially in the southeast of the aquifer, the denitrification process causes a decrease in NO3 concentration. These findings can contribute to effective water resource management in this strategic aquifer by understanding the controlling mechanisms of physicochemical composition and identifying potential groundwater pollution sources.

Vulnerability assessment and mapping of hazard pollution is raised on as an important management strategy to protect the karst. Karstic aquifers in semi-arid regions of the West of Iran with regard to the natural conditions of the region, are susceptible to contamination. Estimation of amount and vulnerability mapping of aquifers in the karst religion of Bistoun- Paraw – Kermanshah plain against poullution emissions using the COP model are theaims of this study. This model using of three parameters - covering layer (O), concentration of flow (C) and regime of precipitation (P) - assesses the vulnerability of karst water resources against pollution. The results show that %31/4of the area has located in the zone of average vulnerability and %30/7of area has been in the low ​​vulnerability area and %37/9of the area has taken a very low vulnerabilities value. The later zone has been included  most part of the plain. Major areas of low and moderate vulnerabilityzones has been located in the high part of the area on wherethe developed limestone territory of karst formations is found. Vegetation cover of these regions areforest-steppe vegetation where is located in the low vulnerability zone and without vegetation cover where is in the moderate vulnerability zones. The latest has over 800 mm Precipitation. Totally, the Parameters that have  most important role in  vulnerability level in the areaare C, P and O respectively.

The irregular exploitation of groundwater aquifers in Shahriyar Plain has caused the drop of ground-water level in the region. Artificial nourishment of aquifers can increase the size of ground-water storage, reduce its level drop, and also prevent the advance of brine and drying of the aqueducts. In this study, we tried to integrate GIS and Boolean logic in order to identify the best areas for artificial recharge in Shahriar Plain. So, the seven factors (slope, permeability, thickness of alluvium, portability, both drop zones, land use and electrical conductivity) of water samples were specified in GIS and then respective maps were prepared. Then, using the acquired weight of each layer, maps for each weighted factors of locating were integrated. Using Boolean logic, final maps were prepared in two classes: suitable and unsuitable. Finally, the best place for the implementation of artificial recharge of aquifers in the region was identified. Results indicated that the suitable regions mostly lie in areas with slopes less than 3 % and that they are mostly near Chitgar river.

vulnerability is considered as an inherent talent of underground water system that depending on the sensitivity of the system to anthropogenic effects. Natural vulnerability is based on the geomorphologic features of surface karst, type and level of aquifer recharge and hydrodynamic aquifer karstic aquifer in Fars province is the most important source of water supply for the supplement of drinking water of communities in the province, which are prone to pollution due to the natural conditions of the region and human activities. karstic aquifer of Shispir and Borghan plays a vital role in supplying drinking and agricultural water around them. The aim of this study is to estimate the natural vulnerability karstic aquifer of Shispir and Borghan using the proposed model of Cast action 620, and prioritize the level of aquifer in the field of conservation measures and provide management solutions in order to better protect them in this model. To prepare a natural vulnerability map are used geological maps, soil, vegetation, digital elevation model (10 meter) and precipitation statistics of meteorological stations and vulnerability map is evaluated as three factors of C, O, p. In the end, the region in terms of damage in five levels was classified in very high, high, low, low and very. The results of the COP model show the natural vulnerability of the region is high. In addition, the amount of vulnerability in the two upper and upper floors of this region is about 47 % where is the highest coverage area of that region of Shisper aquifer. The results of this study show the efficiency of the proposed methods by Cast Action 620 to detect and protection of groundwater resources from vulnerabilities and natural pollution.