Pemetaan Parameter Geokimia Air Tanah di Area Das Winongo Kota Yogyakarta

Abstract

This research aims to analyze the quality and geochemical distribution of groundwater in the Winongo watershed of Yogyakarta City, by considering the existing conditions of the region. The research site is located in the center of Yogyakarta City, which is an area with dense community activities. The area is also characterized by its constituent rocks which are young volcanic deposits. This research is important to determine the potential and mapping of groundwater in the location, given the need for clean water which is increasing along with population growth. The method used in this research involves the use of software such as Quantum GIS (QGIS) 3.30.0 to conduct groundwater quality mapping and Origin 2023 to create stiff diagrams and stiff maps. The parameters studied include cations (Na, K, Al, and Cu) and anions (Cl, SO4, and NO3) in groundwater. The results showed that the contents of pH, TDS, DHL, chloride, sulfate, and nitrate can be influenced by domestic activities in the study area. The presence of sodium, potassium and aluminum, meanwhile, can be attributed to the natural source of the constituent rocks. The stiff diagram shows that the dominant ion conditions in the study area are divided into two types, the first type is groundwater type I Na(K)-Cl with 24 sampling points, which is marked in red. The second type is type II Na(K)- SO4 groundwater with 8 sampling points, which is marked with yellow colorKeywords: Mapping, stiff diagram, groundwater, Geochemistry, Winongo Watershed. This means that 75% of the study area has type I groundwater, with dominant cations Na + K and dominant anions Cl and SO4. This study provides a better understanding of groundwater quality in the Winongo watershed of Yogyakarta City and its relationship with the existing conditions of the area. These findings can be useful in groundwater resource management and decision-making related to water supply in the area.