This work assessed the groundwater hydrogeochemistry and the drinking water quality of 10 wells supplying the urban area of Zamora, Michoacán, Mexico. Two sampling campaigns were conducted in May 2018 (dry season) and November 2018 (wet season) to describe the chemistry of the water and its interaction with the rock. Physical and chemical constituents (temperature, pH, electrical conductivity, color, turbidity, solids, total hardness, total alkalinity, chemical and biochemical oxygen demands), major components (Ca²⁺, Mg²⁺, Na⁺, K⁺, SO₄²⁻, PO₄³⁻, HCO₃⁻, CO₃²⁻, Cl⁻, N-NO₃⁻, and N-NH₃), as well as trace elements (As, Fe, Mn, Ba, Al, Sb, Co, V, Cu, Cd, Cr, Ni, Zn, Tl, Pb) were analyzed. Results showed groundwater with a slight tendency to alkalinity. The hydrogeochemical facies observed are Ca²⁺-HCO₃⁻ in all sites. Hydrochemical diagrams indicate immature, cold, non-saline, and uncontaminated water with short residence time. Water–rock interaction predominates. The water in the study area is appropriate for drinking use according to Mexican and international regulations with an excellent quality in 7 wells and good in the other 3.

The present study shows the effect of Nb on a Ti matrix to fabricate composites via the conventional powder metallurgy for medical applications. Ti powder mixture compacts with different Nb contents were obtained from the conventional pressing and sintering technique. The sintering behavior was evaluated using the dilatometry technique, and the microstructure was studied using scanning electron microscopy (SEM) and X-ray diffraction (XDR). The mechanical properties were obtained from simple compression tests, and the corrosion resistance was determined from a standard three-electrode arrangement in Hank’s solution. The results showed that the Nb in the Ti matrix limits the evolution of sintering depending on the Nb content. Nb slightly accelerates the phase transition temperature. The microstructure and X-rays revealed that biphasic α + β-Ti structures can be obtained, in addition to retaining the β-Ti phase and forming the martensitic phases α′ and α″ of Ti. Likewise, the mechanical behavior showed a Young’s modulus of 10–45 GPa, which is close to that reported for human bones. Furthermore, the circuit analysis revealed that the Ti-Nb sintered systems were conditioned by the surface oxide layer and that the oxide layer formed within the residual pores of the sintering process. Finally, it was demonstrated that adding Nb to the Ti matrix increases the corrosion resistance and that contents close to 15 wt.% of this element have the best results.

This study uses physicochemical data and the geochemistry of major and minor ions to identify and describe groundwater flow patterns and hydrogeochemical characteristics in the Lake Cuitzeo basin. Located in the central-western region of Mexico, the basin is bounded by active faulting, subsidence, and hydrothermal activity along its margins. The study describes groundwater flow patterns, water types, water-rock interaction processes, and their relationship with geological faults traversed by the groundwater. Between 2022 and 2023, water quality was analyzed at 44 deep wells and seven springs. In situ measurements of physicochemical parameters were taken, and the concentrations of major and minor ions were plotted on D’Amore, Mifflin, and Piper diagrams. Seven hydrogeological environments were identified through which groundwater flows, promoting the weathering of Ca-Na-Mg silicates. Geological faults are directly related to flow directions, predominantly southwest-northeast. The primary recharge areas are located in the southwestern sector, where basic silicate rocks are dominant, leading to elevated Mg2+ concentrations due to feldspar leaching. The predominant hydrogeochemical processes include silicate rock weathering, ion exchange, carbonation, water mixing, calcite precipitation, and gypsum dissolution. Three groundwater flow systems were identified: 82% of the flow is local, distributed throughout the basin; 16% is intermediate flow, concentrated in the central and northern areas; and 2% is deep circulation flow, found along the southern margin of the lake.

We conducted a water balance analysis in a temperate forest catchment at the Alto-Fresno Ecohydrological Research Station in central Mexico to characterize the forest’s water yield. The various components of the hydrological cycle in forest ecosystems were measured and characterized, including precipitation, soil moisture, evapotranspiration, rainfall interception, precipitation partitioning, and runoff discharge. Evapotranspiration was estimated using the Penman-Monteith model, with meteorological data collected in situ and a crop coefficient (Kc) adapted for the studied forest. Since all variables of the forest water balance were measured, we used the water balance equation to estimate deep percolation, or water recharge, in the catchment. The results show that between June 2012 and May 2013, total annual precipitation was 895.0 mm, and interception loss amounted to 32.4 mm (3.63 % of total precipitation). The change in soil water content was -56.6 mm (-6.32%). Evapotranspiration was estimated at 621.1 mm (69.4 %), total discharge at 123.0 mm (13.7%), and deep percolation at 61.9 mm (6.92 %). In terms of water yield, each hectare of forest produced an average of 1,222.83 m³ year⁻¹ of discharge and 619.0 m³ year⁻¹ of deep percolation.