Carlos Alejandro Salazar , Roberto Cesar de Mendonça Barbosa , Isabela Apoema Gomes de Souza , Marta Edith Velásquez David , Andressa Resende Soares , Diego Wenderson Venâncio
{"title":"Potholes and shear zones deformation in sandstones: Central Amazon basin","authors":"Carlos Alejandro Salazar , Roberto Cesar de Mendonça Barbosa , Isabela Apoema Gomes de Souza , Marta Edith Velásquez David , Andressa Resende Soares , Diego Wenderson Venâncio","doi":"10.1016/j.jsames.2025.105435","DOIUrl":"10.1016/j.jsames.2025.105435","url":null,"abstract":"<div><div>A pothole is a form related to morphogenetic processes that occur in rock outcrops (such as granites), which are particularly susceptible to water physical and chemical weathering processes, generally in humid tropical climates. In the center of the Amazon basin, waterfalls, rapids streams, and knickzones with the development of potholes, are formed in the beds of several rivers (Urubuí and their tributaries) that erode sandstones from the Silurian Nhamundá Formation. To elucidate the origin of these potholes, there are highlights on analyzing the susceptibility to erosion processes, variations in texture, mineral composition, and strain deformation recorded in quartzarenite to subarkosic sandstones. Panholes are observed and associated with knickzones, where ruptile dextral simple shear zone systems and their conjugate structures influence the drainage network. This search shows that the potholes are spatially positioned at the intersections of tectonic structures which, in addition to the dissolution processes of the sandstone framework, allow the development of large-scale potholes, such as in the Mutum waterfall. They were formed by morphodynamic processes in river valleys carved out of the Nhamundá Formation.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105435"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Thalia Veronica Lazo Campos , Jéssica Carneiro de Souza , Daniela Mariano Lopes da Silva
{"title":"Nitrogen and phosphorus cycling in the hyporheic zone: A scientometric approach to research in Brazil","authors":"Thalia Veronica Lazo Campos , Jéssica Carneiro de Souza , Daniela Mariano Lopes da Silva","doi":"10.1016/j.jsames.2025.105441","DOIUrl":"10.1016/j.jsames.2025.105441","url":null,"abstract":"<div><div>Hyporheic zone, due to its constant contact with water flows, plays a crucial role in nutrient cycling. Despite global advances in understanding the hyporheic zone, its importance, functions, fauna, and the ecological processes that occur there, there are still areas that require further investigation, both in Brazil and internationally. This study conducted a scientometric analysis of research on nutrients, specifically nitrogen and phosphorus, in the hyporheic zone, focusing on its temporal and geographical evolution. The main journals, authors, countries, and research lines were identified, with a particular focus on Brazil. A total of 483 articles related to nitrogen and 238 to phosphorus were selected and analyzed using the VOSviewer software. The results showed growing interest over the past two decades, with the United States, several European countries (the United Kingdom, Germany, Spain, France, among others), and China being the main contributors to this research, although there are still unexplored biomes and ecosystems. The analysis of graphs and networks revealed the presence of small research groups that are not well connected. Additionally, it was observed that studies on nitrogen are more abundant and multidisciplinary compared to those on phosphorus. In Brazil, most of the few studies were conducted in the last seven years. This work provides a solid foundation for future research on biogeochemical processes in the hyporheic zone.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105441"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pablo D. González , Nicolás Foix , José O. Allard , Mariano Hernández
{"title":"Volume Special Issue Tectonostratigraphic Evolution of Patagonia: Preface","authors":"Pablo D. González , Nicolás Foix , José O. Allard , Mariano Hernández","doi":"10.1016/j.jsames.2025.105439","DOIUrl":"10.1016/j.jsames.2025.105439","url":null,"abstract":"<div><div>This Volume Special Issue of the Journal of South American Earth Sciences is dedicated to honoring the career of Professor Dr. Raúl Eduardo Giacosa, a distinguished geologist in Stratigraphy, Structural Geology, and Tectonics of Patagonia, Argentina. Throughout his tenure at the Servicio Geológico Minero Argentino (SEGEMAR), Dr. Giacosa has made pioneering contributions to various topics, including basement geology, stratigraphy of the volcano-sedimentary cover, brittle-to-ductile deformation, structural and kinematic analysis, tectonics, and related mineral resources of Patagonia. His dedication, innovative research, and steadfast mentorship have profoundly impacted the field, leaving a lasting legacy that inspires future generations. This special issue pays tribute to his remarkable achievements and extends heartfelt gratitude for his enduring influence and the contributions of all who made this issue possible.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105439"},"PeriodicalIF":1.7,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Thenmozhi Thangarasu , Hanan Abdullah Mengash , Randa Allafi , Hany Mahgoub
{"title":"Spatial prediction of soil salinity: Remote sensing and machine learning approach","authors":"Thenmozhi Thangarasu , Hanan Abdullah Mengash , Randa Allafi , Hany Mahgoub","doi":"10.1016/j.jsames.2025.105440","DOIUrl":"10.1016/j.jsames.2025.105440","url":null,"abstract":"<div><div>Soil salinity significantly affects agricultural productivity and land sustainability, necessitating efficient monitoring and predictive strategies. This study leverages remote sensing data and machine learning algorithms to spatially predict soil salinity across the Puerto Vallarta region, covering an area of 716.03 km<sup>2</sup>. To enhance prediction accuracy, a diverse set of indices were employed, including Salinity Indices (SI 1, SI 2, SI 3, and SI 11), Intensity Indices (INT 1 and INT 2), Brightness Index (BI), Soil-Adjusted Vegetation Index (SAVI), Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI), and the ratio of spectral bands (B2 and B5). These indices deliver appreciated understandings into soil and vegetation properties, allowing accurate classification and salinity assessment. Soil salinity was categorized into five classes: Very Low (16.54%), Low (23.16%), Moderate (21.97%), High (19.95%), and Very High (18.38%). The machine learning models employed for this study included Random Forest (RF), Artificial Neural Network (ANN), and Support Vector Machine (SVM). Among these, RF exhibited the highest prediction accuracy (92.1%), followed by ANN (89.5%) and Support Vector Machine (86.2%). These results underscore the potential of RF as a robust tool for analyzing spatially complex environmental datasets. Integrating remote sensing parameters and machine learning algorithms demonstrates an effective approach for mapping and managing soil salinity. The findings support sustainable land management by pinpointing critical salinity zones that need urgent intervention. Furthermore, the methodology established in this learning can be practical to other regions facing parallel challenges. This research highlights the significance of data-driven approaches in environmental monitoring and resource management.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105440"},"PeriodicalIF":1.7,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Germán Guillén-Arandía , Rafael García-Ruiz , Avto Goguitchaichvili , Miguel Ángel Cervantes Solano
{"title":"Evolution of magnetic declination in South America since the 17th century","authors":"Germán Guillén-Arandía , Rafael García-Ruiz , Avto Goguitchaichvili , Miguel Ángel Cervantes Solano","doi":"10.1016/j.jsames.2025.105434","DOIUrl":"10.1016/j.jsames.2025.105434","url":null,"abstract":"<div><div>Magnetic declination, the first measurable angular component of the magnetic field was longtime considered as an essential element to facilitate the navigation. Direct, historical measurements of the Earth Magnetic Field's components were commonly carried out during maritime exploration campaigns. Therefore, this invaluable source of information provides an almost unique tool to reveal the ‘geomagnetic past’ of our planet. Thanks to the development (and continuous updating) of historical and global geomagnetic databases, it is now possible to access a numerous geomagnetic field measurement. In particular, 400 years of continuous declination data are available for South America. The primary objective of this study is to estimate the temporal and spatial variation of historical declination values and try to define some fine characteristics of the geomagnetic field. A database of 12,462 well-distributed declination measurements across South America including the margins of Atlantic and Pacific Oceans, was compiled. The whole area was divided into six sub-regions in Brazil (2), Peru (1), Chile (1), Argentina (1) and Uruguay (1) in order to obtain local paleosecular variation curves and meet the mandatory requirement of relocation error procedure. These curves were generated using the Bootstrap algorithm and the penalized cubic spline method. The paleosecular variation curves were compared with currently available global geomagnetic models. Three local curves showed significant differences from the models due to the relatively uneven distribution of the geomagnetic data. First and second temporal derivative of paleosecular variation curves revealed the most significant fluctuations while the global data analysis confirms the existence of the so-called westward drift.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105434"},"PeriodicalIF":1.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ivan Javier Rojas-Castillo , Bruno Mazzorana , Pablo Iribarren-Anacona , Duilio Fonseca-Gallardo , Jorge Berkhoff , Gonzalo Durán , Andrés Iroume
{"title":"Hydro-morphological reconstruction of the Blanco River in the eruptive event 2008: Variables that influenced the change of the channel course in Chaitén, Chile","authors":"Ivan Javier Rojas-Castillo , Bruno Mazzorana , Pablo Iribarren-Anacona , Duilio Fonseca-Gallardo , Jorge Berkhoff , Gonzalo Durán , Andrés Iroume","doi":"10.1016/j.jsames.2025.105412","DOIUrl":"10.1016/j.jsames.2025.105412","url":null,"abstract":"<div><div>Chaitén, a city in Chilean Patagonia, was hit by lahar flows from the Blanco River in May 2008 following a massive volcanic eruption. This cascade process resulted in the avulsion of the active channel of the Blanco River, dividing the city into two sectors, destroying built environments, and causing displacement of the local population. Hydrodynamic studies in the area have generally been based on post-event environmental conditions. However, an exhaustive reconstruction of the hydrodynamic behavior and associated river dynamics has not been performed. More fundamentally, no clear methodological approach has been proposed to accomplish this task. The present study addresses these challenges by applying non-conventional methods to reconstruct the initial and boundary conditions of the event and to trace the intervening factors that decisively influenced the hydrogeomorphic adjustments in the distal river segments. The reconstruction of the initial and boundary conditions of the event was performed by collecting primary and secondary information (using mixed methods and applying information triangulation). A conceptual model of the hydro-geomorphic evolution of the Blanco River in May 2008 was generated, elucidating the role of rainfall and morphodynamical responses and effects in the Blanco River and emphasizing the hydraulic behavior of the Blanco River bridge. Through the detailed reconstruction of the hydro-geomorphic processes, it could be corroborated that the channel responses were not exclusively due to the volcanic eruption but instead to a combination of massive sediment injections into the fluvial system, the intensity and spatiality of the precipitation pulses (associated with the presence of a frontal system and an atmospheric river), the mobilization of inorganic and organic sediments and the interaction of the flow with the Blanco River bridge.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105412"},"PeriodicalIF":1.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Monitoring land subsidence using Sentinel-1A, persistent scatterer InSAR, and machine learning techniques","authors":"Usha S , Eatedal Alabdulkreem , Nuha Alruwais , Wafa Sulaiman Almukadi","doi":"10.1016/j.jsames.2025.105433","DOIUrl":"10.1016/j.jsames.2025.105433","url":null,"abstract":"<div><div>Land subsidence is a significant environmental issue in coastal regions, leading to infrastructure damage and increased vulnerability to flooding. This study focuses on monitoring land subsidence in the coastal region of Maceió using Sentinel-1A Synthetic Aperture Radar (SAR) data in conjunction with Persistent Scatterer Interferometry (PSI) and machine learning (ML) techniques. Sentinel-1A data, including both ascending and descending track datasets, were utilized to capture ground displacement over time. The analysis incorporated a range of environmental variables, including slope, elevation, aspect, curvature, land use/land cover (LULC), geology, Hillshade, and flow direction, which were used as training sets for the ML models. The Persistent Scatterer in SAR (PSI) technique was employed to extract precise displacement data from the SAR imagery, revealing land subsidence trends over the study period. ML models were applied to analyse the correlation between the subsidence patterns and environmental factors, enhancing the accuracy and reliability of the results. The ML techniques utilized included regression models and classification algorithms to predict and interpret subsidence rates and spatial distribution. The results show that land subsidence in Maceió ranged from 52 mm/year to −60 mm/year, with significant spatial variability. The findings highlight areas of rapid subsidence that may be linked to geological and anthropogenic factors, such as urbanization and groundwater extraction. Incorporating machine learning methods into this analysis improved the spatial resolution of the subsidence estimates, offering a more comprehensive understanding of the underlying causes and trends. This study demonstrates the potential of integrating remote sensing, InSAR, and ML techniques for monitoring and understanding land subsidence in coastal regions. The results can inform mitigation strategies and urban planning in areas susceptible to subsidence and related hazards.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"155 ","pages":"Article 105433"},"PeriodicalIF":1.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christian Creixell , Juan Díaz-Alvarado , Javier Álvarez , Carmen Rodríguez , Ricardo Velásquez , Verónica Oliveros
{"title":"Episodic magmatism and segmentation of the Gondwanan arc in Chile (21–38°S): Insights into Carboniferous to early Permian subduction processes and deformation","authors":"Christian Creixell , Juan Díaz-Alvarado , Javier Álvarez , Carmen Rodríguez , Ricardo Velásquez , Verónica Oliveros","doi":"10.1016/j.jsames.2025.105421","DOIUrl":"10.1016/j.jsames.2025.105421","url":null,"abstract":"<div><div>The Gondwanan cycle unfolds along the southwestern margin of Gondwana during the late Paleozoic, driven by the subduction of the proto-Pacific plate beneath the continental margin. Its geological record in Chile comprises accretionary complexes that emerge discontinuously along the coast, together with belts of igneous rocks, predominantly intermediate in composition, which constitute the coeval Gondwanan magmatic arc.</div><div>Based on extensive geochemical data, geochronology and field observations, the magmatic belt can be divided into three segments: Northern (21°–27° S), North-Central (27°–31° S), and Southern-Central (33°–38° S), according to varying percentages of exposed plutonic and volcanic rocks, the ages of magmatic pulses, and proximity to coeval accretionary complexes. The northern and north-central segments exhibit continuous activity for over 50 million years, from 330 to 280 Ma, with arc-trench distances of about 100–150 km. In contrast, the Southern-Central segment is located close to the accretionary complex (0–30 km) and concentrates its magmatic activity during the Pennsylvanian (322-300 Ma).</div><div>The marked episodic behavior of the Gondwanan arc in the northern and north-central segments is characterized by a High Magma Addition Rates (HMAR) event at 300-279 Ma that coincides with a peak in basal accretion within the coastal prism and localized orogeny in the foreland (San Rafael orogenic stage). Despite these events, various petrogenetic indicators suggest that both crustal and mantle magma sources remained stable throughout most of the Gondwanan cycle, with no evident arc thickening during the HMAR event. These deformation processes correlated in time with the diachronous arrival of oceanic reliefs to the margin, previous to onset of the Choiyoi Province.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105421"},"PeriodicalIF":1.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniela I. Schmidt , Diego A. Winocur , Pierre Pitte , Anahí Benitez
{"title":"GLOF modelling of Torre Lake and its potential impact in El Chaltén, Santa Cruz, Argentina: Preliminary results","authors":"Daniela I. Schmidt , Diego A. Winocur , Pierre Pitte , Anahí Benitez","doi":"10.1016/j.jsames.2025.105417","DOIUrl":"10.1016/j.jsames.2025.105417","url":null,"abstract":"<div><div>The northern slope of the Cerro Solo, located in Southern Patagonian Andes, has a significant instability which could trigger a sudden release of large amounts of water contained in the Torre proglacial lake (Glacial Lake Outburst Flood, GLOF). Such events are highly complex phenomena, with diverse origins and often catastrophic consequences. This paper examines the potential for a rapid increase in the water level caused by a sudden landslide into the Torre Lake, which could lead to an overflow. The subsequent release of water could flood the Fitz Roy River, with the potential to produce damage downstream in El Chaltén locality and its surroundings, affecting inhabitants and tourists visiting the area.</div><div>In this study, various empirical methods for predicting landslide-generated impulse waves are compared. These methods are then applied to model the potential GLOF. The advantages and disadvantages of this procedure are analyzed and discussed. Based on the estimation of peak discharges of lake outflow using empirical formulas, a two-dimensional (2D) hydrodynamic model was implemented to simulate two potential outburst scenarios, with estimated peak discharges of 1166 m<sup>3</sup>/s and 1769 m<sup>3</sup>/s. The possible inundation extent and its impact were assessed based on the depth of water and the flow velocity. This study is a preliminary step toward understanding the magnitude of a potential future GLOF event and what elements that could be affected in order to develop an effective response to minimize impact.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105417"},"PeriodicalIF":1.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Thieres George Freire da Silva , Ana Karlla Penna Rocha , Alanderson Firmino de Lucas , Gabriel Thales Barboza Marinho , Alexandre Maniçoba da Rosa Ferraz Jardim , Luciana Sandra Bastos de Souza , Abelardo Antônio de Assunção Montenegro , Werônica Meira de Souza
{"title":"Streamflow prediction based on the soil and water assessment tool in the Pajeú river basin, Brazilian semiarid","authors":"Thieres George Freire da Silva , Ana Karlla Penna Rocha , Alanderson Firmino de Lucas , Gabriel Thales Barboza Marinho , Alexandre Maniçoba da Rosa Ferraz Jardim , Luciana Sandra Bastos de Souza , Abelardo Antônio de Assunção Montenegro , Werônica Meira de Souza","doi":"10.1016/j.jsames.2025.105420","DOIUrl":"10.1016/j.jsames.2025.105420","url":null,"abstract":"<div><div>It is considered highly important for developing strategies to conserve water resources and minimize environmental impacts, especially in places with low rainfall and high potential evapotranspiration, such as semiarid regions. In this context, the main objective of this study was to evaluate the ranking of the most sensitive parameters and the calibration and validation of the streamflow between 1976 and 2018 in the Pajeú river Basin using the SWAT hydrological model. The SUFI-2 algorithm, integrated into the SWAT-CUP software, was used for sensitivity analysis (SA), calibration (from 1976 to 1995), validation (from 1999 to 2018), and uncertainty analysis. Results showed that only seven parameters related to land use and land cover (initial SCS runoff curve number for moisture condition II – CN2), groundwater (baseflow alpha factor – ALPHA_BF, groundwater delay time – GW_DELAY, threshold depth of water in the shallow aquifer required for return flow to occur – GWQMN, and groundwater “revap” coefficient – GW_REVAP), and runoff (slope length for lateral subsurface flow – SLSOIL and lateral flow travel time – LAT_TTIME) were considered the most sensitive and were subsequently calibrated. Thus, CN2 was reduced by 28%, consequently decreasing surface runoff. ALPHA_BF showed a slow response to recharge, while GW_DELAY affected groundwater discharge by 47 days. GWQMN increased by approximately 2586.9 mm, improving streamflow simulation. GW_REVAP, with a value close to zero, exhibited a reduction trend in the groundwater table during the dry season and in the upward movement of water to the root zone. The basin slope class ≤8% increased SLSOIL to 29.41 m, which in turn increased LAT_TTIME by 99.47 days. SWAT also simulated maximum streamflows associated with extreme precipitation events in an acceptable manner. The Floresta gauging station achieved more satisfactory performance, as observed in the percentage of observations covered by the 95% prediction uncertainty – 95PPU (P-factor), the average thickness of the 95PPU band divided by the standard deviation of the measured data (R-factor), the coefficient of determination (R<sup>2</sup>), Nash-Sutcliffe efficiency (NSE), and percent bias (PBIAS), with respective values of 0.68, 1.05, 0.64, 0.63, and 6.5% for calibration. Therefore, investigating hydrological processes in this region allows for the development of water planning strategies, given the significant impacts on water resources and agricultural production, especially during drought events.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105420"},"PeriodicalIF":1.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}