## 3 Results and Discussion
### Spatial and Temporal Variations of Measuring Indicators  
A total of 23 water quality parameters were analyzed at four sampling wells. These sampling wells are located within the urban area of the city of Cuernavaca, which has different elevations as shown in Figure 2.  
The land use and soil classifications in the study area are shown in Figures 3 and 4, respectively. These figures demonstrate that P1 is in a wooded area with little human settlement, close to the annual rainfed agricultural area. The dominant soil type in this area is Luvic phaeozem which is characterized by organic matter and scarce carbonates. This sample site is next to an oak-pine forest land-use zone. Sample sites P2, P3, and P4 have similar characteristics because they are in irrigated agricultural areas close to the urban area. These sites are in a Pelic vertisol soil characterized by high mineral content.  
Figure 3: Land use classification of the Cuernavaca aquifer.  
Figure 2: Elevations of the Cuernavaca aquifer.  
Figure 5 presents the spatial interpolation of the water quality parameters in the Cuernavaca aquifer. The highest values for all the parameters analyzed were observed in sampling point two (P2), while sampling point one (P1) presented the lowest values. This situation could be related to the soil type in the area. Since the highest elevation is observed in P1, the rest of the sample points located in lower elevation areas could be influenced by the erosion, transport, and deposition of contaminants.  
Figure 6 presents the spatial behavior of the major ions. The presence of ions in the sampling wells is due to interactions with the geological material of the aquifer, natural processes of rock dissolution, and ion leaching. This figure shows that higher concentrations of ions were found at the P2. At this site, groundwater is not suitable for domestic use according to WHO [28] guidelines. The spatial distribution of these chemical elements highlights the vulnerability of the aquifer, especially at P2. Since the concentrations of ions at P1, P3, and P4 sites are similar, they could be considered reference values for the major  
Figure 4: Soil classification of the Cuernavaca aquifer.  
Figure 5: Spatial behavior of physicochemical parameters in the Cuernavaca aquifer.  
tions in the Cuernavaca aquifer. It is noteworthy that the concentration of ions in all the groundwater samples was found to be within the WHO desirable limits for agricultural irrigation [6; 28].  
Figure 7 presents the temporal variation of the water quality parameters from 2012 to 2019. No trends, seasonal or cyclic patterns were found in the groundwater quality data. The time series also demonstrated that P2 showed higher values in almost all parameters. Lower concentrations of the physicochemical and major ions are observed at P1 since this site is at a higher elevation where the runoff of anthropogenic contaminants is significantly low. Similar values are presented by [PERSON] et al. [14], who evaluated the groundwater of Nanganur county in India. Based on these results, they consider that groundwater quality does not represent health risks for drinking water use and only recommend groundwater delluoridation.  
Table 3 presents the ANOVA statistical analysis of the groundwater quality parameters. This table showed that 15 parameters had a statistically significant variation from a spatial point of view. However, only 4 groundwater quality parameters showed a temporal significant variation.  
Figure 6: Spatial behavior of major ions in the Cuernavaca aquifer.  
Figure 7: Variation of water quality parameters over time (2012–2019) at P1 (-), P2 (-), P3 (-), P4 (-), P5 (-).