Rogelio Ledesma

• Master of Engineering
• Tecnológico de Monterrey

The identification of nitrate (NO3⁻) sources and biogeochemical transformations is critical for understanding the different nitrogen (N) pathways, and thus, for controlling diffuse pollution in groundwater affected by livestock and agricultural activities. This study combines chemical data, including environmental isotopes (δ²HH2O, δ¹⁸OH2O, δ¹⁵NNO3...

This study analyzed the dynamics of major ions and trace elements along the groundwater flow path of the coastal sedimentary Todos Santos aquifer in Baja California Sur, Mexico, moderately impacted by anthropogenic activities. The results indicate that the elements Ca²⁺, Mg²⁺, Ba²⁺, Sr²⁺ and Li⁺ are mobilized from the aquifer matrix during seawater...

Environmental isotopes and hydrochemistry are useful tools for the study of groundwater flow systems. Groundwater from Tecate area in Peninsula of Northern Baja California, Mexico, was sampled for chemical and stable isotopes analyses. Four groundwater types were identified, predominating the Mixed-HCO3 facie. A tendency of calcium to the sodium an...

The quality of the groundwater supplying drinking water to the Guadalajara metropolitan area has deteriorated due to both endogenic and exogenic processes. Previous studies of this complex neotectonic volcanic environment suggest that the sources of contamination here are underground fluids derived from an active volcanic center and surface wastewa...

The La Paz aquifer system (Baja California Sur, Mexico) is under severe anthropogenic pressure because of high groundwater abstraction for urban supply (city of La Paz, around 222,000 inhabitants) and irrigated agriculture (1900ha). In consequence, seawater has infiltrated the aquifer, forcing the abandonment of wells with increased salinity. The o...

In order to understand and mitigate the deterioration of water quality in the aquifer system underlying Guadalajara metropolitan area, an investigation was performed developing geochemical evolution models for assessment of groundwater chemical processes. The models helped not only to conceptualize the groundwater geochemistry, but also to evaluate...

This chapter provides an overview of groundwater management in urban Latin America. It is illustrated with the two cases of Mexico City and São Paulo, the two largest metropolises in the region. The authors demonstrate that groundwater has a crucial and strategic role as a source of urban water and in sustainable development but that its significan...

Zona Citrícola is an important area for Mexico due to its citriculture activity. Situated in a sub-humid to humid climate adjacent to the Sierra Madre Oriental, this valley hosts an aquifer system that represents sequences of shales, marls, conglomerates, and alluvial deposits. Groundwater flows from mountainous recharge areas to the basin-fill dep...

Nitrate isotopic values are often used as a tool to understand sources of contamination in order to effectively manage groundwater quality. However, recent literature describes that biogeochemical reactions may modify these values. Therefore, data interpretation is difficult and often vague. We provide a discussion on this topic and complement the...

We used environmental tracers (CFCs, 18O, 2H, 3H, 14C, and water chemistry) to analyze the groundwater quality and flow system underlying and supplying part of the Metropolitan Area of Guadalajara, México. Most of the samples showed isotopic signatures, indicating recharge from local meteoric precipitation. Significant tritium concentrations were i...

We used environmental tracers (CFCs, 18O, 2H, 3H, 14C, and water chemistry) to analyze the groundwater quality and flow system underlying and supplying part of the Metropolitan Area of Guadalajara, México. Most of the samples showed isotopic signatures, indicating recharge from local meteoric precipitation. Significant tritium concentrations were i...