Laboratory of Water Resources and Environmental Isotopes
RESEARCH IN PROGRESS
Inclusion of Isotopic Techniques in Monitoring and Modeling Programs of Urban Watersheds (ISOTRACK)
High environmental quality standards that positively affect public health, the environment, and ecosystem services are objectives of sustainable urban growth. In this context, urban water systems, which comprise supply infrastructure and natural water storage and drainage systems, are being pressured by increasing demands and climate change, requiring better understanding and study to build more resilient cities. Despite this urgency, urban hydrology is still under-researched and understood, especially concerning the relationships between humans/climate/physical environment and water supply. In this regard, stable hydrogen and oxygen isotopes serve as excellent tracers of water movement, allowing for better understanding of these relationships, yet they are still rarely used in urban hydrology studies. The present project aims to incorporate isotopic information into hydrological monitoring programs, enabling the evaluation of the pathways water takes and the role of green areas in contrast to heavily urbanized areas within the urban eco-hydrological compartmentalization, thereby contributing to integrated urban planning through the proposition of nature-based solutions for cities in the interior of São Paulo.
Participants: Didier Gastmans - Coordinator / Amauri A. Menegário - Participant / Rodrigo Lilla Manzione - Participant / Daniel Marcos Bonotto - Participant / Vladimir Eliodoro Costa - Participant / Aroldo Geraldo Magdalena - Participant / Juliana Cortez Barbosa - Participant / Kleper de Oliveira Rocha - Participant / Reginaldo Barboza da Silva - Participant.
Funding: Financier of Studies and Projects - Financial Assistance.
Multi-Isotopic Approach for Groundwater Dating and Paleoclimatic Reconstruction of the Aquifers in the Potiguar Basin (CE-RN, Brazil)
The sustainable use of groundwater from confined aquifers in semi-arid regions requires an integrated understanding of its movement and storage, as increasing demands indicate overexploitation, as observed in the Chapada do Apodi (CE-RN, Brazil), where economic development is linked to irrigated fruit farming, made possible by groundwater availability. The Jandaíra aquifer (unconfined and karstic) and the Açu aquifer (porous and confined) constitute a transboundary resource, where evidence of overexploitation has already been observed. In this context, the use of isotopic tracers to understand water movement in these aquifers can assist in better management. Stable isotopes of H and O are used to understand hydrological processes such as aquifer recharge and their association with climatic conditions, while radioactive isotopes of H and C determine the mean residence times of groundwater. Recently, the use of noble gases has been incorporated into hydrological studies, providing important information on groundwater ages and paleoclimatic conditions during recharge. Water-rock interaction processes can be assessed using Sr isotopes. This project aims to tackle the scientific challenge of understanding the movement and storage of groundwater in the Açu and Jandaíra aquifers through isotopic techniques, with the following objectives: (i) determine groundwater residence times using radioactive isotopes and ⁴He accumulation rates; (ii) determine the paleotemperatures of groundwater recharge using noble gases and stable isotopes; and (iii) assess water-rock interaction, contributing to a better understanding of climate evolution in Northeastern Brazil, providing important information on groundwater renewal rates in these units, enabling better resource management.
Members: Didier Gastmans - Coordinator / Veridiana Teixeira de Souza Martins - Member / Sibele Ezaki - Member / Roberto Kirchheim - Member / Vinicius dos Santos - Member / José Claudio Viégas Campos - Member / Zulene Almada Teixeira - Member / José Guilherme Filgueira - Member / Natália de Souza Arruda - Member / Nicolas Quintan Bernardo - Member / Idembergue Barroso Macedo de Moura - Member / Jürgen Sültenfu - Member / Leandson Roberto Fernandes de Lucena - Member / Milton Morais Xavier Junior - Member / Vladimir Eliodoro Costa - Member / Zayra Christine Sátyro dos Santos - Member / Fernando Mazo D'Affonseca - Member / José Gescilam Sousa Mota Uchôa - Member / Filipe Alem Hildebrando - Member / Luana Charlotte D’Barsoles Frederick - Member.
Funding: National Council for Scientific and Technological Development - Financial support.
ISO-ATTO: Importance of the Amazon in the Development of Convective Systems and Regional Vapor Transport
Climate projections for South America predict an increase in convective activity over the continent, causing a greater number of extreme rainfall events, impacting a growing population, especially those living in risk areas. In this sense, understanding the role played by the Amazon region in modulating surface-atmosphere interactions, controlling greenhouse gases (GHGs) and aerosols is essential, as the region is considered the largest convective center on the planet and is responsible for vapor propagation to the central-southern region of Brazil through the influence of the so-called atmospheric rivers. Stable isotopes of Hydrogen and Oxygen present in the water molecule have been used as an important tool in understanding hydroclimatic phenomena, enabling the investigation of the origin and movement of water, which is vital in the context of studies on interaction in the atmosphere-hydrosphere system and the possible impacts caused by extreme events in tropical areas. The proposed project aims to understand the existing connection between the Amazon Rainforest and the atmosphere and its relationships with the formation of convective events, using: measurement data obtained from instruments installed on the towers of the Amazon Tall Tower Observatory (ATTO) project, which provide a unique opportunity to analyze the behavior of surface fluxes during convective events and the transition from shallow to deep convection, observations from the Precipitation Micro Radar, the isotopic composition of precipitation (high-frequency intra-event sampling), and meteorological and isotopic data from orbital sensors. The project will enable an understanding of surface-atmosphere coupling and the processes of evapotranspiration and precipitation recycling relevant to the role of the Amazon as a source of moisture for precipitation in other regions of Brazil.
Members: Didier Gastmans - Coordinator / Ricardo Sánchez-Murilo - Member / Vinicius dos Santos - Member / ANA MARÍA DURÁN QUESADA - Member / Matthias Schneider - Member / Harald Sodemann - Member / Zayra Christine Sátyro dos Santos - Member / Rafaela Rodrigues Gomes - Member.
Funding: National Council for Scientific and Technological Development - Financial support.
Anthropic Influences on Compartments of the Hydrological Cycle in Micro-Watersheds of Central Amazonia: An Analysis Using Multiple Tracers
The effects of climate change and urbanization processes on water movement, storage, and quality in continental compartments have been observed and described worldwide. However, their impacts in Central Amazonia, where the city of Manaus is located, may be more intense due to uncontrolled land-use conversion and urbanization. The sustainable use of water resources requires an understanding of the mechanisms involved in water movement and storage within the hydrological cycle, as signs of water scarcity and quality degradation have been observed, leading to disputes over safe water sources. In the complex environmental scenario of Central Amazonia, this project aims to determine the sources of water flows and quality alterations related to urbanization processes, with a special focus on the interactions between groundwater and surface water in two micro-watersheds: Igarapé Asú, located in the Cuieiras Biological Reserve, and Igarapé Educandos, situated in an urbanized area. This will be achieved through hydrochemical, isotopic, and hydrological techniques. The project seeks to delineate flow relationships and seasonal variations in contributions to observed stream discharges, estimate groundwater transit times within aquifers, and identify anthropogenic impacts on water quality and flow interactions. The ultimate goal is to establish scientific foundations for proposing environmental restoration measures focused on water resources.
Members: Didier Gastmans - Coordinator / Amauri A. Menegário - Member / Vinícius Santos - Member / Ricardo Sánchez-Murilo - Member / Lucas Vituri Santarosa - Member / Graziele Beatriz Lima - Member / Laura de Simone Borma - Member / Cléber Santos - Member / Carlos Daniel Meneghetti - Member / Sávio José Filgueiras Ferreira - Member / Márcio Luiz da Silva - Member / Rafaela Gomes - Member.
Funding: São Paulo Research Foundation - Financial support / Amazonas Research Foundation - Financial support.
ISOTOPIC MONITORING PROGRAM (H, O, and C) OF THE MEDIUM AND LOWER AQUIFERS OF THE ARARIPE AND AÇU BASINS IN THE POTIGUAR BASIN (CEARÁ, BR)
The main objective of this work is to establish an isotopic monitoring program, lasting three years, for the groundwater extracted through deep wells from the Medium and Lower Aquifers of Cariri and the Açu Aquifer in the Potiguar Basin, Ceará. The municipalities that will be covered are: Crato, Juazeiro do Norte, Barbalha, Missão Velha, and Mauriti (Medium and Lower Aquifers, respectively), and Quixeré and Alto Santo (Açu Aquifer), involving the execution of laboratory isotopic analyses and interpretations of Deuterium, Oxygen-18, and Carbon-14 and Carbon-13 isotopes in groundwater.
Members: Didier Gastmans - Coordinator.
HYDROGEOLOGICAL STUDIES FOR THE ASSESSMENT OF THE EXPLORATION CONDITIONS OF THE GUARANI, BAURU, AND SERRA GERAL AQUIFER SYSTEMS IN UGRHI 12-BPG
The main objective of this work is to establish an isotopic monitoring program, lasting three years, for the groundwater extracted through deep wells from the Medium and Lower Aquifers of Cariri and the Açu Aquifer in the Potiguar Basin, Ceará. The municipalities that will be covered are: Crato, Juazeiro do Norte, Barbalha, Missão Velha, and Mauriti (Medium and Lower Aquifers, respectively), and Quixeré and Alto Santo (Açu Aquifer), involving the execution of laboratory isotopic analyses and interpretations of Deuterium, Oxygen-18, and Carbon-14 and Carbon-13 isotopes in groundwater.
Members: Didier Gastmans - Coordinator / Edson César Wendland - Member / Carolina Stager Quaggio - Member / Ariane Penteado Constantino - Member / Pedro Medeiros Correa - Member / Hélio Correia da Silva Jhunior - Member.
Funding: Autonomous Water and Sewage Service of Bebedouro - Financial assistance.
Creation and Establishment of the National Network of Isotopes in Rivers (GNIR) in Brazil
Members: Didier Gastmans - Coordinator / Amauri Antônio Menegário - Member / Ricardo Sánchez-Murilo - Member / Roberto Kirchheim - Member.
Funding: International Atomic Energy Agency - Financial assistance.
Multiscale controls and cloud processes related to variations on precipitation isotopic composition of precipitation in Southeastern region of Brazil
This proposal has three main focus regardin isotopic composition in Brazilian teritory: a) based on daily and weekly long term monitoring (2013-2019) on isotopic composition of precipitation in Central region of São Paulo state combined with meteorological data (ground, Reanalysis data and Hysplit model) and avaliable satellite data (ERA-INTERIM) analyze the regional processes, and key drivers that control the observed seasonal variability on precipitation isotopic composition, as well as estimate rainfall type fraction (convective versus stratiform); b) generate a new high resolution (minute to hour) rainfal isotopic data set coupled to Micro Radar observations to evaluate rain generation processes and cloud microphysics associated to rainfall event evolution; c) compare previous isotopic data from GNIP (1960-1980) with new data that will be acquired from recently launched monitoring program by Brazilian Geological Survey in collaboration with IAEA. All the information generated during the project will help hydrological researchers and water managers to deal with groundwater recharge, water resilence in watershed, as well as to contribute on the monitoring network for the Resilience of Headwater Systems and Water Availability for Downstream Communities Across the Americas. .
Members: Didier Gastmans - Coordinator / Vinícius Santos - Member / Roberto Kirchheim - Member / Lucas Vituri Santarosa - Member / Graziele Beatriz Lima - Member.
Funding: International Atomic Energy Agency - Financial aid.
Hydrological Science as a Key to Promote Effective Water Use and Conservation in Complex Productive Systems
This proposal for CAPES PRINT aims to support the development of an interdisciplinary and international network of scientists and graduate students to advance an exchange of knowledge, as well as a long-term research project, using hydrological science to promote water conservation in variable economic environments water-dependent, such as agriculture and related agroindustry, as well as associated ecosystems, in countries involved in this proposal. Together, all the participants attempt to understand the influences on the hydrological cycle due to the main economic activities water-dependent, such as corn and soybean in the USA, sugarcane in Brazil, and coffee in Costa Rica, and the role played by ecological conservation programs, integrating knowledge, data, and models from comparable study sites. Based on this initial integration, our proposal will lead toward an intensive educational exchange program between graduate students from the universities involved in this proposal, based on the solution of practical problems related to water issues. Part of the research participants of the proposed network have developed joint research; however, the inclusion of researchers from Kansas State University leads to characterizing this network as a partially consolidated (IRN-2).
Members: Didier Gastmans - Coordinator / Ricardo Sánchez-Murilo - Member / Rodrigo Lilla Manzione - Member / Troy E. Gilmore - Member / Luiz Felippe Gozzo - Member / Jan Boll - Member / Marcellus Caldas - Member / Stacy L. Hutchinson - Member / Wagner Luiz Lourenzani - Member / Ana Elisa Bressan Smith Lourenzani - Member.
Funding: CAPES - Anhanguera Center for Promotion and Social Education - Financial assistance.
Creation and Establishment of the National Network of Isotopes in Rivers (GNIR) in Brazil
The Amazon basin represents the largest freshwater reservoir in the planet, draining an area equivalent to 6.2x106Km2 and discharges about 7.2 Km3 / day to Atlantic Ocean. Due to the intrinsic connection and interdependence between precipitation systems and the Amazon forest, this basin is of high continental relevance for recycled moisture to the atmosphere and regulating climate patterns on the global scale. Similarity, two other large watersheds: São Francisco and Paraná basins, draining the northeastern and southeastern region of Brazil, respectively, denote different hydrogeological conditions and are also important for multiple social-cultural and economic activities. Despite the increasing interest in these regions and the existence of a robust assessments have been scarce and sporadic. Stable isotopes techniques provide a valuable management tool to understand groundwater contribution as baseflow and climate change effects in the water storage capacity in transboundary river basins in Brazil. Therefore, the main goal of this proposal focuses on the analysis of spatial and temporal isotopic patterns from three large river basins in Brazil. The strong involvement of the Geological Survey of Brazil (called here as CPRM) represents along with its institutional networking will ensure the establishment of the surface water isotope monitoring of the country. To guarantee scientific adherence and to turn this initiative into a capacity building opportunity not only for Brazil but for other countries in the region, our proposal includes strong partnerships with two consolidated research groups in Latin America: The Center for Environmental Studies of the São Paulo State University (CEA-UNESP), coordinated by Dr. Didier Gastmans and the Stable Isotopes Research Group (SIL) and Water Resources Management Laboratory from the Universidad Nacional (UNA), Heredia Costa Rica, coordinated by Dr. Ricardo Sánchez-Murillo
Members : Didier Gastmans - Coordinator / Amauri Antônio Menegário - Member / Ricardo Sánchez-Murilo - Member / Roberto Kirchheim - Member.
Financier (s) : International Atomic Energy Agency - Financial aid.
Complementary Isotopic Studies in the Southern, Western, and Eastern Compartments of the Guarani Aquifer System (Brazil) - Groundwater Dating Along Defined Flow Paths
The main purpose of this project is to provide subsidies to improve the Guarani Aquifer System (GAS) hydraulic conceptual model through the evaluation, along defined flow paths, of the hydrochemical and isotopic evolution of GAS groundwater. Groundwater dating using Cl-36 and Kr-81 in the central portion of the Paraná Basin is proposed to complement previous C-14 information. This project has been submitted to participate in the Coordinated Research Project (CRP): Characterization of Fossil Groundwater Systems Using Long-Lived Radionuclides.
Members: Didier Gastmans - Member / Chang Hung Kiang - Coordinator / Maria Rita Caetano Chang - Member / Luis Araguás - Member / Roberto Kirchheim - Member.
Funding: International Atomic Energy Agency - Financial assistance.
A research network for the resilience of headwater systems and water availability for downstream communities across the Americas
Worldwide, human communities rely on water storage from glaciers, snowpack, and groundwater in headwater watersheds. Water supply amount and variability from headwater storage systems to downstream communities are predicted to shift with climate change. Vulnerability of downstream communities depends upon the direction and magnitude of hydrologic change, as well as their ability to adapt. It is critical to understand impacts of warming trends and precipitation variability on headwater storage systems, and the adaptation strategies necessary for long-term water security. The proposed RCN will create capacity to understand the resilience of headwater dependent systems (HDS) to environmental change by coupling knowledge of watershed hydro-climatology and downstream human development in multiple test-bed watersheds across a latitudinal Transect of the Americas. The RCN will focus on three dominant headwater storage types from Canada to southern Chile: 1) glaciers; 2) seasonal snowpack; and 3) rain-fed, and will aggregate expertise in: 1) latitudinal climate change variability using isotope data and modeling; 2) water mass balance of glacier / snow / rainfall systems; and 3) water resource system resilience and adaptation ..
Members : Didier Gastmans - Member / Ricardo Sánchez-Murilo - Member / Jan Boll - Member / Jose Luis Arumí - Member / Mick Stone - Member / Alex Fermier - Member / Julie Padowski - Member / Scott Jasechko - Member.
Stable Isotopes of H and O and Hydrochemistry in the São Francisco 1 Sub-Basin, Alto São Francisco Region, Minas Gerais
This study analyzed the chemical composition of major elements and stable isotopes (H and O) in precipitation, groundwater, and surface water in the São Francisco 1 sub-basin (approximately 14,000 km²), located in the headwaters region of the São Francisco River, an area characterized by fractured aquifer systems and complex geology. Groundwater and surface water exhibited low mineral content, with an average electrical conductivity of 147.2 ± 99.4 μS.cm⁻¹ and 65.7 ± 78.7 μS.cm⁻¹, respectively. The ionic abundance (mEq.L⁻¹) followed the order of Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ for cations and HCO₃⁻ > SO₄²⁻ > Cl⁻ > NO₃⁻ > F⁻ > PO₄³⁻ for anions, with most samples being calcium and/or magnesium bicarbonates. The chemical composition was mainly influenced by water-rock interactions and precipitation during the wet season in surface waters. The isotopic composition of precipitation exhibited a seasonal pattern, with lower values in the wet season (-63.87‰ for δ2H and -9.86‰ for δ18O) and higher values in the dry season (-5.12‰ for δ2H and -2.12‰ for δ18O). The isotopic composition of groundwater remained stable between seasons (-43.71‰ for δ2H and -6.70‰ for δ18O), while that of surface water varied seasonally (-44.95‰ for δ2H and -7.07‰ for δ18O in the wet season, and -38.12‰ for δ2H and -6.14‰ for δ18O during the dry season), reflecting precipitation inputs.
Marcela Aragão de Carvalho Ramos
Funding: Fundação Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), and IAEA (International Atomic Energy Agency).
Modeling of Water Flow in the Upper Aquifer of the Araripe Sedimentary Basin: Strategies for the Protection and Sustainable Management of Water Sources in the Cariri Region (CE)
In the work "Vidas Secas," Graciliano Ramos depicts the arid and relentless reality of the northeastern sertão, where water is as scarce as it is precious. This masterpiece of Brazilian literature prompts us to reflect on the vital importance of water and its intrinsic relationship with the survival and prosperity of communities in the northeastern semi-arid region. In these areas, the availability of surface water resources is limited, which elevates the significance of using groundwater as the primary source of supply. In the southern region of Ceará, in the Chapada do Araripe, both residential and industrial/rural water supply depend exclusively on groundwater. The increase in urbanization and intensification of agriculture lead to indiscriminate well drilling that affects water quality, water management, and sanitation, creating a critical situation in water supply.
The study area is situated in the Araripe Sedimentary Basin (BSA), the largest groundwater reserve in Ceará. In this area, hydrogeology governs the aquifer system, divided into Upper Aquifer, Santana Aquiclude, Middle Aquifer, Brejo Santo Aquiclude, and Lower Aquifer (DNPM, 1996). Due to the geological characteristics of the region, several natural springs originate on the slopes of the chapada, providing water to supply communities for their various activities (TEIXEIRA, 2017). By understanding the hydrogeological characteristics of the area, it is possible to assess the future availability and quality of groundwater through mathematical flow modeling using Visual Modflow software. The modeling will be conducted at the Gravatá spring in Crato – CE. The data includes topography, groundwater levels, physicochemical and isotopic analyses, and estimates of recharge and water balance, provided by COGERH and LARHIA. These studies will support effective water resource management, comprehending the recharge and discharge systems of the watersheds.
Mariana Fávero Duarte
Funding: Fundação de Apoio à Pesquisa, Ensino e Extensão (FUNEP).
Impacts of Seasonal Variation in Groundwater Availability on the Hydrological Regime of the Pantanal Basin
The Pantanal basin has a complex hydrological dynamics that is closely linked to its structural control and the seasonalities of the rainfall regime. At the same time, the economic exploitation of natural resources and the consequent changes in vegetation cover, along with climate changes, clearly influence the hydrological dynamics of the region, alongside the perception of changes in water availability, the acceleration of erosional/depositional processes, the consequent reduction in river base levels, and also fluvial avulsion. This context makes it urgent to conduct an interdisciplinary assessment of the hydrological aspects of the region, seeking to evaluate the impact of anthropogenic factors on the hydrological regime as a way to identify trends and patterns of changes over time.
The objective of this research is to assess the seasonal impacts of groundwater availability on the hydrological regime of the Pantanal basin. For this evaluation, gravitational signals obtained from the GRACE satellite will be used and converted into water column measurements, in addition to series of surface water height obtained from in situ measurements of river levels collected by ANA stations. This approach will enable a linear correlation to be established between the dynamics of surface and groundwater and detect oscillations in the total water column in the basin due to scenarios of high and low flow, considering the role of this context in the hydrological cycle and evaluating the correlation of the observed processes with anthropogenic coefficients of climate change and/or suppression of vegetation cover.
Bruno Valdambrini
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).
Technological Solutions of Artificial Intelligence Based on Complex Adaptive Systems in Integrated Water Resources Management
The multidisciplinarity of the variables that determine the intensity and pathways of water flows between atmospheric, surface, and groundwater reservoirs throughout the Hydrological Cycle—such as climate, hydrology, and geology—are conditioned by mutual adaptation to climate changes and land use conversion resulting from anthropogenic actions, making the rational use of water complex. Integrated Water Resources Management (IWRM) is based on the joint assessment of surface and groundwater, seeking sustainable solutions to meet the demands of consumptive uses, and constitutes a Complex Adaptive System (CAS), where the connection of reservoirs promotes the constant rebalancing of components. Artificial Intelligence (AI) techniques are an emerging approach in the construction of CAS, due to their ability to analyze large volumes of data and correlations between nonlinear functions, as well as to represent phenomena in temporal and spatial scales.
This project aims to simulate the adaptation of a Water Resources Management Unit (UGRHI) in the state of São Paulo in response to scenarios of increasing water demand associated with economic development and climate changes, using AI techniques. The balance between reservoirs will be estimated through simple water balance equations, which will support the projections of scenarios and rebalancing in response to adaptations of the CAS. It is intended to investigate supervised machine learning models for classification and regression. The goal is to create a tool that will assist IWRM, enhancing knowledge of the water resources landscape in the basin and contributing to the optimization of consumptive uses and the functions and ecosystem services of water.
Carolina Stager Quaggio
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Fundação Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).
Conservation and Monitoring of Groundwater in the Cariri Region
With monthly measurements of 10 water samples from wells (each containing water from a different formation or location), physicochemical parameters are used to determine the quality and conservation of groundwater.
Gabriela Vitória Firmino
Funding: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).
Environmental Isotopes Associated with Recharge and Circulation Mechanisms in the Aquifers, Araripe Basin, Ceará, Brazil
The Araripe Basin region (Cariri Cearense) is fundamentally important in the hydrogeological context of the state of Ceará. Human supply is 100% provided by groundwater. Therefore, the continuous quantitative monitoring of aquifer systems, along with isotopic studies, is essential to observe the recharge of aquifer systems in various zones of the Basin, especially in areas already identified with a deficit in supply versus demand, considering urban growth and agricultural expansion, which are the largest users.
As natural markers, stable isotopes of water have been routinely used in hydrological studies and have significantly contributed to our understanding of climate and hydrological processes, especially related to current and past recharge processes in aquifers in semi-arid regions, such as the case presented here, where water resources are limited and groundwater represents, in many cases, the only or priority source.
To improve the management of the "Medium Aquifer System" (SAM) of the Araripe Basin, the Companhia de Gerenciamento de Recursos Hídricos do Ceará (COGERH) implemented an isotopic monitoring network within the Company's systematic long-term monitoring program. In this context, analyses of stable isotopes have been included. The sampling for this project is scheduled to take place over 36 (thirty-six) months, from November 2022 to October 2025. At the end of the monitoring period, the data will be compiled with laboratory results to obtain the signature of this hydrogeological environment, allowing inferences about water circulation in the aquifer, along with the indication/interpretation of recharge mechanisms. Additionally, this data will be cross-referenced with the balance of the supply versus demand relationship for the various uses attributed to extractions in the SAM.
Guilherme Filgueira
Funding: Companhia de Gestão dos Recursos Hídricos (COGERH).
Multi-Isotopic and Noble Gas Approach for Understanding the Circulation and Recharge Conditions of the Açu Aquifer's Groundwater in the Potiguar Basin
In northeastern Brazil, groundwater represents an important water source. In the context of climate change and population growth in semi-arid regions, knowledge about the flow conditions, storage, and hydrogeochemical evolution of groundwater contributes to better management of water resources in these areas. The record of overexploitation and salinization in the Açu Aquifer, located in the Potiguar Sedimentary Basin (BSP) in the states of Ceará and Rio Grande do Norte, raises the necessary alert for further studies in the region.
This study aims to understand the flow, storage, and residence time conditions of groundwater in the Açu Aquifer through the integration of hydrogeochemical data, environmental isotopes (δ²H, δ¹⁸O, δ¹³C, and ¹⁴C), and noble gases (He, Ne, Ar, Kr, Xe), as well as to comprehend the past climatic conditions during its recharge. The flow and confinement systems of the Açu Aquifer present a consistent pattern represented by increasing residence times from the recharge zone located at the edge of the Chapada do Apodi.
Current climatic patterns in the region differ from the past conditions during the Holocene/Pleistocene transition, which were identified as being between 4 and 7°C cooler in previous studies. Therefore, using climatic tracers such as stable isotopes and noble gases is expected to provide insights into the climatic conditions during the recharge of groundwater, enabling a better understanding of the paleoclimatic framework of the region. Additionally, interpretations regarding the residence time of these waters and their mixing with underlying saline waters contribute to the understanding of the flow systems and management of this aquifer.
Natália S. Arruda
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).
Hydrogeochemical Assessment of Groundwater in the Chapada do Araripe
The Chapada do Araripe, located in the southern region of Ceará state, is an area of great archaeological, ecological, geological, and paleontological significance, attracting academic and scientific interest due to its unique characteristics. The region has a high population density and faces significant demands to sustain regional development. In this context, the extraction of groundwater emerges as a viable option to meet local water needs. However, it is crucial to conduct comprehensive studies to determine the age and quality of groundwater, ensuring its sustainable and conscious extraction, as well as securing the region's water supply and preventing contamination that could compromise its use.
A Scientific Initiation project, carried out in partnership between UNESP and COGERH (CE), aims to collect and analyze groundwater samples from tubular wells to determine the age of these aquifers and provide relevant information for local managers and researchers interested in the region. Hydrogeochemical studies play a crucial role in this context, allowing for an understanding of the interaction processes between groundwater and the aquifer rocks, which is fundamental for the proper management of water resources.
Nicolas Quintan Bernardo
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).
Climate Controls on Isotopic Variability of Rainfall in Central Amazon
Stable isotopes of hydrogen (¹H/²H) and oxygen (¹⁶O/¹⁷O/¹⁸O) in precipitation are effective tools for investigating the dominant meteorological parameters during rainfall events. The distribution of precipitation and the organization of convective events in Central Amazon are influenced by complex climatic dynamics, such as the movement of the Intertropical Convergence Zone (ITCZ) and local vapor recirculation processes. Aiming to revive studies on this topic in the region, which were interrupted in the 1990s, the master's project intends to assess the climatic factors (both local and regional) responsible for the isotopic variability of precipitation in Central Amazon.
To achieve this, a joint analysis will be conducted involving the isotopic composition of precipitation, meteorological data, information from the Reanalysis project, and HYSPLIT backward trajectory modeling. These tools will allow for the evaluation of the atmospheric systems and local processes that generate rainfall in the region and their impact on the origin and trajectory of water vapor. The results aim to highlight the importance of observing stable water isotopes for understanding atmospheric processes and to contribute to the development of climatic models for the Amazon, particularly in the context of climate change.
Rafaela Rodrigues Gomes
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).
Tracking Water Pathways in Urban Areas: Isotopic Perspective of the Hydrological Cycle in Araraquara (SP)
The main objective of this project is to utilize stable water isotopes to understand the urban hydrological cycle of the city of Araraquara, São Paulo, making it a pioneering study in Brazil. This project is part of research funded by FINEP, titled "Inclusion of Isotopic Techniques in Monitoring and Modeling Programs of Urban Watersheds (ISOTRACK)," and the postdoctoral researcher is supported by a PD-AF scholarship.
Vinicius dos Santos
Funding: PD-AF Scholarship from UNESP/PROPG.
Effects of ENSO Events on the Amazon: Micrometeorological Analysis and Implications for Meso-scale Convective Events and Moisture Transport to the S/SE Region of Brazil
The Amazon is the largest convective center on the planet, connecting with various other regions while providing numerous ecosystem services locally and regionally. However, the area is under threat from anthropogenic interventions such as deforestation and disordered occupation, in addition to being highly vulnerable to natural disturbances associated with climatic anomalies. In light of these concerns, the objective of this project is to investigate how El Niño phenomena impact the atmospheric moisture balance in the Amazon and how this effect influences the behavior of meteorological variables within the atmospheric boundary layer; the development and production of rainfall from meso-scale convective systems within the Amazon Basin; and moisture transport to the southern/southeastern region of Brazil. With a theoretical foundation and more robust data, this project also aims to understand the relationship between these alterations and moisture distribution. This study contributes to the understanding of climatic phenomena and regional ecosystems, bringing important practical implications. The results may assist in defining environmental management policies, adaptation strategies to climate change, and provide crucial knowledge for the sustainability of the Amazon and surrounding regions, highlighting the importance of preserving this biome, which is critical for global climate balance.
Zayra Christine Sátyro dos Santos
Funding: National Council for Scientific and Technological Development (CNPq).
Long-term Observations of the Isotopic Composition of Rainfall in the Central Region of São Paulo State
Assessments of time series data regarding the variability of the isotopic composition of rainfall, derived from continuous observations, have been used to understand the effects of climate change, particularly in temperate regions. However, there is a gap in this type of analysis in tropical regions, primarily due to the lack of continuity in these observations. Therefore, studies in tropical regions are crucial for evaluating the influence of meteorological parameters on the isotopic composition of rainfall, as these regions have a unique climate that significantly affects the distribution of rainfall regimes.
This project aims to evaluate the historical series of isotopic data from the GNIP station at the Environmental Studies Center of UNESP/Rio Claro, given that the climate in the central region of São Paulo is directly impacted by various atmospheric systems that influence isotopic composition variation. The research seeks to understand the local and regional climatic dynamics that interfere with the isotopic composition of precipitation in the municipality of Rio Claro and its variabilities through the analysis of a historical series. Rainfall collection in Rio Claro has been ongoing since 2014, providing 10 years of data for analysis, which will be correlated with local and regional climatic parameters. For synoptic analysis, data will be obtained from the Reanalysis Project, using the ERA5/Copernicus and GIOVANNI/NASA platforms, while local meteorological data will be sourced from measurement stations at the Environmental Studies Center and the Environmental Planning and Analysis Center, located at the same site as the isotopic event collection.
Amanda Rodrigues Soares
Funding: São Paulo Research Foundation (FAPESP) and Coordination for the Improvement of Higher Education Personnel (CAPES).
Assessment of Intrinsic Vulnerability and Contamination Risk of the Guarani Aquifer System in Recharge Areas in Uruguay
The objective of the project is to assess the intrinsic vulnerability and contamination risk of the recharge areas of the Guarani Aquifer System (SAG) based on the characterization of the physical environment in its outcropping areas.
Members: Didier Gastmans - Member / Gerardo Veroslavsky - Coordinator / Lucas Vituri Santarosa - Member / Alberto Maganelli - Member / Natalie Aubet - Member / Lucia Samaniego - Member / Roberto Carrion - Member.
Application of Stable Isotopes in Understanding Processes in the Hydrological Cycle: Precipitation and Small Watersheds in the State of São Paulo - Brazil
Stable isotopes (δ2H and δ18O) are excellent tracers of water movement in the hydrological cycle, serving as auxiliary tools in interpreting the origins of flows within watersheds and the climatic controls on precipitation, which enables their use in paleoclimatic reconstruction studies. In tropical areas, climatic factors that govern the isotopic composition of precipitation remain a controversial issue in the scientific community. While some authors propose that the isotopic composition of precipitation is influenced by aspects of local climatic dynamics, others advocate the importance of global-scale processes, such as Rayleigh distillation. Environmental isotopes have also been used as complementary tools in understanding hydrological processes in watersheds, aiding in the comprehension of the mechanisms and processes involved in the formation of stream discharge, estimating mean residence times of water, identifying the origins of flow components, and calibrating and/or validating hydrological models through the estimation of hydrological parameters.
Based on the processes involved in the isotopic transformations that water undergoes along its path in the hydrological cycle in continental areas, this project aims to evaluate the isotopic variations of precipitation in several locations in the state of São Paulo, seeking to understand the governing climatic factors (local or regional) and assess the seasonal variability of the isotopic composition in both subsurface and surface components in small watersheds within the Jacaré Pepira River sub-basin, aiming to determine the Mean Transit Times in these watersheds, thereby contributing to the quantification of the water balance.
Members: Didier Gastmans - Coordinator / Amauri A. Menegário - Member / Ludmila Vianna Batista - Member / Vinícius Santos - Member / Ricardo Sánchez-Murilo - Member / Rodrigo Lilla Manzione - Member / José Silvio Govone - Member / Barbara Saeta Farinha - Member / Lucas Vituri Santarosa - Member.
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo - Financial assistance.
Variation on Stable Isotopes in Modern Precipitation in Tropical Region of Brazil: Key to Understand Variations in Stable Isotope Composition from Unconfined Aquifers in São Paulo State
Continuous monitoring of the isotopic composition of precipitation at the GNIP station installed at CEA in Rio Claro (GNIP Code: 8374701), combined with the monitoring of the isotopic composition of unconfined and shallow aquifers located in the same geographical region of São Paulo state, can contribute to the understanding of atmospheric circulation models, as well as allowing for the assessment of the recharge of these aquifers.
Members: Didier Gastmans - Coordinator / Chang Hung Kiang - Member / Ludmila Vianna Batista - Member / Roberto Naves Domingos - Member / Vinicius dos Santos - Member / Sarah Maria Rodrigues dos Santos - Member.
Funding: International Atomic Energy Agency - Financial assistance.
Evaluation of the Temporal Evolution of the Piezometric Surface, Influenced by Pumping, of the Guarani Aquifer System in the City of Araraquara
Continuous monitoring of water levels in an abandoned well, drilled in the Guarani Aquifer System in the central region of the municipality of Araraquara, will allow for the assessment of existing pumping conditions in the city through the construction of a numerical model, aiding in the management of groundwater resources.
Members: Didier Gastmans - Coordinator / Bruno Scalvi - Member.
Hydrogeochemistry and Quality of Surface Waters in the Alto Jacaré-Pepira Basin (SP)
The expansion of the monitoring network in the Alto Rio Jacaré Pepira Watershed (SP), through the determination of the Water Quality Index (WQI), will enable the understanding of local variations in water quality within the basin due to anthropogenic activities. The WQI is an important index for assessing water quality, supporting integrated water resource management actions.
Members: Didier Gastmans - Coordinator / Ludmila Vianna Batista - Member.
Hydrogeochemistry and Isotopic Hydrology of Groundwater from the Serra Geral Aquifer in the State of São Paulo
Aquifers associated with basaltic rocks represent an important source of groundwater supply in various regions around the globe, due to the low salinity of their waters and the large volume of water stored in these units, related to the extensive territorial coverage typically occupied by volcanic lava flows and the thickness of these layers. In Brazil, a significant magmatic event that occurred in the early Mesozoic in the Paraná Sedimentary Basin, represented by the basalts of the Serra Geral Formation, constitutes an important aquifer in its area of occurrence. In the western region of the state of São Paulo, groundwater from the Serra Geral Aquifer (SGA) is responsible for supplying numerous cities settled on this unit. The main objective of this project is to conduct hydrochemical and isotopic studies of the groundwater in the SGA in the State of São Paulo, seeking to establish the chemical reactions that occur within the aquifer associated with water-rock interaction, which impart the hydrochemical characteristics observed in the groundwater of the unit, as well as to evaluate past climatic conditions during the recharge of these waters based on variations in the contents of stable isotopes observed. This study involves conducting chemical and isotopic analyses of groundwater, as well as petrographic and mineralogical studies of the basaltic rocks that constitute the unit. For processing this information, the application of graphical and statistical methods (univariate and multivariate) is proposed, along with speciation calculations and geochemical modeling using specific software.
Members: Didier Gastmans - Coordinator / Chang Hung Kiang - Member / Amauri Antônio Menegário - Member.
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo - Financial Support.
Isotopic Tracers Revealing Water Movement in Watersheds of the State of São Paulo
In a global scenario of climate change, the sustainable use of water resources requires an understanding of the mechanisms involved in the movement and storage of water in the compartments of the hydrological cycle, as signs of water scarcity are observed and disputes over reliable sources of supply are occurring. Future management solutions must consider the climatic factors involved in rainfall formation, the resilience capacity of watersheds, and their connection to groundwater, enabling the adoption of protective actions aimed at increasing the supply of good quality water. In this context, various tracers have been used to understand water movement and determine its residence times in the subsurface. Stable isotopes (2H/1H and 18O/16O) are excellent tracers of water movement in the hydrological cycle, being used as auxiliary tools in interpreting the origins of flows within watersheds and the climatic controls on precipitation, which allows their use in paleoclimatic reconstruction studies. In tropical areas, the climatic factors governing the isotopic composition of precipitation remain a controversial issue in the scientific community. While some authors propose that the isotopic composition of precipitation is influenced by aspects of local climatic dynamics, others advocate the importance of global-scale processes, such as Rayleigh distillation. Environmental isotopes have also been used as a complementary tool to understand hydrological processes in watersheds, aiding in the comprehension of mechanisms and processes involved in infiltration and aquifer recharge, the formation of discharge in watercourses, the estimation of mean residence times of water, the identification of the origins of flow components, as well as the calibration and/or validation of hydrological models through the estimation of hydrological parameters. In this sense, the present research project has two main thematic axes, aiming to address the scientific challenge of elucidating water movement in watersheds of the state of São Paulo through the use of a series of isotopic tracers, seeking to understand the variability of the isotopic composition of precipitation and its relationship with atmospheric processes at various temporal and spatial scales, and to assess the spatial and temporal variability of the isotopic composition of surface waters in large watersheds.
Members: Didier Gastmans - Coordinator / Amauri A. Menegário - Member / Vinícius Santos - Member / Ricardo Sánchez-Murilo - Member / Troy E. Gilmore - Member / Carolina Stager Quaggio - Member / Lucas Vituri Santarosa - Member.
Funding: São Paulo Research Foundation - Financial assistance.
Application of Isotopic Tracers to Determine Water Residence Times in Multi-Scale Water Management
The sustainable use and management of groundwater and its interactions with rivers and lakes require qualitative and quantitative knowledge of the hydrogeological characteristics of the aquifer, as well as the dynamics of water movement and the use of conceptual hydrogeological models. Hydrological observations, combined with estimates of aquifer properties, are necessary for numerical models. Recently, isotopic techniques, such as groundwater dating (which involves the time between water recharge and sampling), have been used to develop conceptual models and calibrate numerical models. A large number of isotopes can be used to estimate ages ranging from decades to thousands of years, with each tracer presenting its own advantages and disadvantages. Collection procedures are distinct for each tracer, as are the models necessary for age corrections, which can be complex concerning different hydrogeological environments. The objective of this project is to combine the experiences of scientists from the University of Nebraska-Lincoln Water Cluster Research Group in dating "new waters" with the expertise of researchers from UNESP in determining ages of "old waters," enhancing ongoing projects (including the FAPESP project). Workshops are planned, as well as new collaborative projects in the Guarani Aquifer (Brazil) and the High Plain Aquifer (USA).
Members: Didier Gastmans - Coordinator / Rodrigo Lilla Manzione - Member / Troy E. Gilmore - Member / Aaron Mittelstet - Member / Jesse Korus - Member.
Funding: São Paulo Research Foundation - Cooperation.
Origin of Flows, Nitrate and Residence Times of Water in Hydrographic Basins of the State of São Paulo
In a global climate change scenario, the sustainable use of water resources requires an understanding of the mechanisms involved in the movement and storage of water in the hydrological cycle compartments, since signs of water scarcity are observed and disputes over safe sources of supply have been occurring. Future management solutions should consider the resilience of hydrographic basins and their connection to groundwater, enabling the adoption of actions to protect and preserve water resources, with the aim of increasing the supply of good quality water. In this context, several tracers have been used to understand the movement of water and to determine their residence times in the subsurface. Stable isotopes (2H / 1H and 18O / 16O) are excellent tracers of water movement in the hydrological cycle, being used as auxiliary tools to understand hydrological processes in hydrographic basins, helping to define the mechanisms and processes involved in the infiltration and recharge of aquifers , formation of the discharge of water courses, in the estimation of the average residence times of the water, in the identification of the origin of the components of the flow, as well as in the calibration and / or validation of hydrological models through the estimation of hydrological parameters. Several isotopes can be used to estimate the ages of groundwater, each with its time interval of application, depending on the half-life time. Two examples in which isotopes can be useful for groundwater management are: (i) determination of recharge rates, and (ii) estimate of the average transit times (TMT) of groundwater in hydrographic basins, understood as TMT, the time elapsed between the recharge (infiltration) of the water and its discharge from the aquifer in the river. In both cases, these tracers can be used to formulate hypotheses about the interaction of surface and groundwater, making it possible to formulate water resources management proposals and / or how changes in climate can affect these water systems. Currently, in the state of São Paulo, the greatest concern regarding the contamination of groundwater by nitrate is associated with urban point sources. Little attention is paid to the large diffuse sources existing in agricultural regions, which, due to the increased use of nitrogen fertilizers, can lead to an increase in nitrogen storage in the soil and in shallow aquifers, which can increase rapidly due to the time span elapsed between the introduction of nitrogen during recharge until its discharge into bodies of water connected to these aquifers. The determination of the contributions of groundwater discharge to rivers is essential for understanding the dynamics of the nitrogen cycle in agricultural areas, especially when it comes to identifying and anticipating problems related to the quality of water resources. In this sense, the present research project has two main thematic axes, having as scientific challenges to elucidate the movement of water in hydrographic basins of the state of São Paulo, through the use of a series of isotopic tracers, seeking to understand the spatial and temporal variability of the isotopic composition of surface waters in large hydrographic basins and to evaluate the concentrations of nitrate in surface waters and the contributions from the discharge of groundwater, in a hydrographic basin of agricultural characteristic in the recharge area of the Guarani Aquifer System, as well as to estimate the average times of traffic.
Members: Didier Gastmans - Coordinator / Vinícius Santos - Member / Ricardo Sánchez-Murilo - Member / Troy E. Gilmore - Member / Lucas Vituri Santarosa - Member / Camila de Lima - Member.
Financier (s): National Council for Scientific and Technological Development - Financial assistance.
Hydrosphere
The Work Plan presented in this document is the result of negotiations between ITAIPU, the Hydrogeological Research Laboratory of the Department of Geology at the Federal University of Paraná (UFPR), and the Itaipu Technology Park Foundation (FPTI). These negotiations began in the second half of 2016 during a working meeting between the technical teams of the institutions, aiming to study the interaction between surface and groundwater resources in the Paraná 3 Watershed.
Thus, the Hidrosfera project was developed with the primary objective of studying groundwater and its relationship with surface water, both in terms of quantity and quality, thereby understanding the phenomena and processes involved that allow for the estimation of water availability in the Paraná 3 Watershed. The partnership between FPTI, UFPR, and ITAIPU in this agreement is characterized by generating a knowledge base and providing scientifically relevant information to support sustainable water resource management systems in the region.
Members: Didier Gastmans - Member / Rodrigo Esteves Rocha - Member / Gustavo Barbosa Athayde - Coordinator / Lia Nogueira Grapelli - Member / Graziele Beatriz de Lima - Member.