Journal of South American Earth Sciences最新文献_第3页

Evidence in rocks, soil, and water of hydrolysis processes causing sodicity and regressive mortality in arid environments 岩石、土壤和水的水解过程在干旱环境中导致碱化和退化死亡的证据

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-10 DOI: 10.1016/j.jsames.2025.105514

Erika Loyola-Martínez , José A. Ramos-Leal , Janete Morán-Ramírez , Ulises Rodríguez-Robles , Sanjeet K. Verma

{"title":"Evidence in rocks, soil, and water of hydrolysis processes causing sodicity and regressive mortality in arid environments","authors":"Erika Loyola-Martínez , José A. Ramos-Leal , Janete Morán-Ramírez , Ulises Rodríguez-Robles , Sanjeet K. Verma","doi":"10.1016/j.jsames.2025.105514","DOIUrl":"10.1016/j.jsames.2025.105514","url":null,"abstract":"<div><div>This work aims to identify the origin of water and soil salinization in an arid area. Sodicity is a type of salinity found in arid or desert soils, influencing soil nutrient loss.</div><div>Petrography, mineralogy, X-ray diffraction, and hydrogeochemistry techniques were applied to address water and soil salinity in the arid area of Tierra Nueva. A textural analysis classified the soil types derived from the alteration of the dominant rocks in the region. Hierarchical cluster analysis, principal component analysis, and hydrogeochemistry identified the types of water and the main routes of the water evolutionary processes (dissolution, precipitation, and ion exchange).</div><div>The results indicate that salinization can be geogenic and anthropogenic, in the first case, the aquifer composed of igneous rocks of andesitic and rhyolitic composition, release sodium during weathering. Anthropic activities in the region also increase salinization. Three dominant processes were identified: i) where water-rock interaction predominates; (ii) mixing with hydrological influences of irrigation return; (iii) which is affected by ion exchange in the clayey soil and the capillary effect with high evaporation, which subsequently intensifies the salinity of the water and soil in the Tierra Nueva region.</div><div>The sodicity levels in water and soil suggest that regressive mortality affects resilient species such as mesquites (<em>Prosopis</em> spp) and huisache (<em>Acacia farnesiana</em>). Due to osmotic stress, these species form nodules and cracks in their stems, leading to regressive mortality.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"160 ","pages":"Article 105514"},"PeriodicalIF":1.7,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852005","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}

引用次数: 0

Fractured and porous aquifer recharge in semiarid regions and the relevance of soil covers: A review for Caetité area, Bahia, Brazil 半干旱地区断裂和多孔含水层的补给及土壤覆盖层的相关性：巴西巴伊亚州卡埃蒂特地区综述

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-09 DOI: 10.1016/j.jsames.2025.105525

André Walczuk , José Eloi Guimarães Campos , Júlio Henrichs de Azevedo

{"title":"Fractured and porous aquifer recharge in semiarid regions and the relevance of soil covers: A review for Caetité area, Bahia, Brazil","authors":"André Walczuk , José Eloi Guimarães Campos , Júlio Henrichs de Azevedo","doi":"10.1016/j.jsames.2025.105525","DOIUrl":"10.1016/j.jsames.2025.105525","url":null,"abstract":"<div><div>Groundwater is a valuable natural resource in areas susceptible to arid and semiarid climates. In this research, the phreatic surface dynamics of shallow fractured and porous aquifers of Caetité, state of Bahia, Central Brazil, was investigated. Water level position was assessed by GRACE satellite data and 28 monitoring wells for the period from 2003 to 2024. Phreatic surface trends for all datasets are coherent to rainfall patterns described by precipitation moving averages and the Standardized Precipitation Index (SPI), respectively. The use of GRACE, however, is best applicable to soil hosted aquifers rather than to fractured systems. Recharge estimations considered the Water Table Fluctuation RISE methodology and vary depending on aquifer type. The annual storage variations obtained based on satellite and instruments installed in porous media (weathered rock and soil) suggests that 19–27 % of the year rainfall (130–177 mm/year) are annually converted into effective recharge. In systems composed solely of fresh fractured rocks rates drop to 3 % (24 mm/year). A relevant finding is the two-way effects of soil thickness in the recharge process. While <em>pedon</em> favors recharge on wetter conditions, it may diminish or equate annual storage variations to settings where no or thin soil covers are present. Data corroborates that aquifer recharge under semiarid conditions are sensitive to minor precipitation variations. Finally, it is proposed that geological setting must be considered when evaluating climate change impacts on groundwater, as infiltration is impacted by precipitation, evapotranspiration, and physiographical properties (relief pattern, geology, soil type and climate).</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105525"},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816857","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}

引用次数: 0

Granulometry of mineral soils affecting pollen records and paleoenvironmental reconstitution in South America Grasslands 影响南美洲草原花粉记录和古环境重建的矿质土壤颗粒测定法

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-09 DOI: 10.1016/j.jsames.2025.105510

Eliara Marin Piazza , Mirian Lago Valente , Soraia Girardi Bauermann , Cristina Gouvêa Redin , Elias Frank de Araújo , José Miguel Reichert

{"title":"Granulometry of mineral soils affecting pollen records and paleoenvironmental reconstitution in South America Grasslands","authors":"Eliara Marin Piazza , Mirian Lago Valente , Soraia Girardi Bauermann , Cristina Gouvêa Redin , Elias Frank de Araújo , José Miguel Reichert","doi":"10.1016/j.jsames.2025.105510","DOIUrl":"10.1016/j.jsames.2025.105510","url":null,"abstract":"<div><div>Mineral soils are generally considered unsuitable for pollen analysis because of poor pollen quality, low spore preservation, and disturbed stratigraphy. Our study aimed to determine the influence of particle size composition in the pollen record and contribute to reconstituting the paleoenvironmental history during the late Holocene in the Brazilian Pampa biome. Palynological, soil particle size, and radiocarbon dating (<sup>14</sup>C) analyses were performed on fifteen mineral soil samples of a Leptic Luvisol, collected in a grassland-forest ecotone area in the Brazilian Pampa biome, in southern Brazil. In the palynological analysis we identified 36 taxa from grassland, 25 from forest, and 9 non-pollen palynomorphs (NPPs). Five paleoecological zones were identified, and <sup>14</sup>C indicated the age of 2630 ± 25 cal yr B.P. at 70 cm depth of soil. The highest values of pollen concentration occurred in the clay loam texture horizon, between 25 and 45 cm, with values of 396.30 cm<sup>3</sup> at 30 cm depth Pollen concentration was lower in sandier soil horizons and higher in clay loam horizon, with a strong inverse relationship with coarse sand (r = −0.78) and positive with silt (r = 0.61) and clay (r = 0.52). These relationships show soil particle size is a fundamental property in pollen preservation, and should be used as a determinant factor when choosing soil type in palynology studies. Our study subsidizes the understanding of the biome flora, which is important for species richness and autochthony, and the results on floristic biodiversity may contribute to flora conservation and recovery of degraded areas in grasslands biome.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105510"},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826167","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}

引用次数: 0

Modeling and spatio-temporal prediction rainfall data applied to mass movements in Belo Horizonte, Minas Gerais - Brazil 巴西米纳斯吉拉斯州贝洛奥里藏特地区群众运动的建模和时空预报降雨数据

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-08 DOI: 10.1016/j.jsames.2025.105524

Bianca Nespoli Cortez , Jandresson Dias Pires , Gabrielle Ferreira Pires , Gérson Rodrigues Dos Santos , Marcos Barreto De Mendonça , Eduardo Antonio Gomes Marques , Nathan Ribeiro Mac Laren Nogueira , Isabel Eustáquia Queiroz Volponi

{"title":"Modeling and spatio-temporal prediction rainfall data applied to mass movements in Belo Horizonte, Minas Gerais - Brazil","authors":"Bianca Nespoli Cortez , Jandresson Dias Pires , Gabrielle Ferreira Pires , Gérson Rodrigues Dos Santos , Marcos Barreto De Mendonça , Eduardo Antonio Gomes Marques , Nathan Ribeiro Mac Laren Nogueira , Isabel Eustáquia Queiroz Volponi","doi":"10.1016/j.jsames.2025.105524","DOIUrl":"10.1016/j.jsames.2025.105524","url":null,"abstract":"<div><div>Disasters associated with natural events are the focus of many studies due to their great potential for negative impacts. Events linked to mass movements caused by rainfall have significantly increased in quantity and magnitude of impact. Rainfall is the main trigger for mass movements and, therefore, its measurement is paramount for understanding, monitoring the natural disasters caused by these events. The lack of a historical rainfall series with spatialized data on an adequate scale is a major limitation for developing risk management studies. Faced with the scarcity of rainfall data interpolated on a regular grid, geostatistics has become useful for generating climate data where observed data are insufficient or non-existent. Thus, this work aimed to apply the geostatistical modeling and spatio-temporal prediction methodology to rainfall data in Belo Horizonte, Minas Gerais - Brazil for use in municipal disaster risk management. Specifically, were evaluated: Kriging and Fixed Station Kriging (FRK). Among these two predictors, FRK obtained more robust and homogeneous results. The kriging variance was used to calculate uncertainties. The FRK method showed less variability in uncertainty estimation. The location of the maximum annual rainfall in one day and the maximum accumulated rainfall in four days were also compared with the village/slum areas and with the distribution of the main areas where mass movements happened. It was found that the mass movements recorded in Belo Horizonte are mostly in regions of villages and favelas. It was observed that even regions with lower rainfall have many occurrences of mass movements, which may indicate that these areas have some conditioning characteristics.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105524"},"PeriodicalIF":1.7,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823966","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}

引用次数: 0

Morphotectonics in intraplate setting: The case of the western border of the São Paulo Basin – Southeastern Brazil 板内环境下的形态构造：以巴西东南部<s:1>圣保罗盆地西部边界为例

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-05 DOI: 10.1016/j.jsames.2025.105511

Marcos Roberto Pinheiro , Fernando Nadal Junqueira Villela , Paola Cianfarra

{"title":"Morphotectonics in intraplate setting: The case of the western border of the São Paulo Basin – Southeastern Brazil","authors":"Marcos Roberto Pinheiro , Fernando Nadal Junqueira Villela , Paola Cianfarra","doi":"10.1016/j.jsames.2025.105511","DOIUrl":"10.1016/j.jsames.2025.105511","url":null,"abstract":"<div><div>In the last decades, many researches have highlighted the role of Neotectonics on landforms in intraplate settings. However, the low magnitude seismicity and the action of erosion and weathering, which obliterates traces of tectonic activity, present great challenges to recent tectonic studies in some regions, such as in the Precambrian basement of South and Southeast Brazil. In this way, the objective of this research is to explore the Neotectonic activity and its relationships with landforms in the transition between the western border of the São Paulo Basin (Paleogene) and the Precambrian basement. In order to achieve this aim, topographic and aeromagnetic lineaments were traced in Shuttle Radar Topography Mission (spatial resolution: 30 m) and aeromagnetic data, respectively, and compared with seismicity data. Structural data were surveyed in outcrops, and paleostresses were computed by the fault-slip inversion with Daisy 3 software. Morphometric indices (Stream Length-Gradient Index, Basin Shape, Asymmetry Factor) were calculated in order to evaluate possible tectonic signatures on landforms, especially in the drainage network. In addition, a detailed morphotectonic map of a subset of the study area was done. The results of this work indicate that the study area shows several traces of tectonic activity (rectilinear water divisors and streams, elbows, asymmetrical valleys, right-angle confluences, knickpoints, elongated drainage basins, triangular facets and hillslope breaks). However, there is not structural data supporting the hypothesis that old shear zones have been reactivated in the current tectonic environment. The strong tectonic control on the landscape seems to reflect particularly an adaptation of the fluvial system to ancient inherited structures printed in the Precambrian basement.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105511"},"PeriodicalIF":1.7,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785719","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}

引用次数: 0

Increasing landslide susceptibility in urbanized areas of Petrópolis identified through spatio-temporal analysis 通过时空分析确定Petrópolis城市化地区滑坡易感性的增加

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-04 DOI: 10.1016/j.jsames.2025.105509

Cheila Flávia de Praga Baião , José Mantovani , Enner Alcântara

{"title":"Increasing landslide susceptibility in urbanized areas of Petrópolis identified through spatio-temporal analysis","authors":"Cheila Flávia de Praga Baião , José Mantovani , Enner Alcântara","doi":"10.1016/j.jsames.2025.105509","DOIUrl":"10.1016/j.jsames.2025.105509","url":null,"abstract":"<div><div>This study conducts a detailed spatio-temporal analysis of landslide susceptibility in Petrópolis, Rio de Janeiro, leveraging data from recorded landslide events between 1985 and 2022. Employing Logistic Regression (LR) and Multiscale Geographically Weighted Regression (MGWR), we generated susceptibility maps for years with the highest landslide occurrences, enabling an evaluation of spatial variability and localized influences of conditioning factors. Significant variables included lithology, land use and land cover (LULC), total precipitation (PRCPTOT), extreme rainfall events (R100), distance from rivers, soil type, slope aspect, elevation, and forest cover. Lithology and LULC showed the strongest positive correlations with landslide occurrences, while forest cover and elevation exhibited protective effects. The model's predictive performance was validated with AUC values ranging from 0.77 to 0.99 and accuracy between 0.77 and 0.97, demonstrating robustness across different temporal scales. Susceptibility maps revealed a temporal increase in areas classified as very high susceptibility, particularly in urbanized zones. These findings address critical gaps in the understanding of landslide dynamics, providing a robust framework for integrating susceptibility maps into disaster risk reduction strategies and urban planning. By identifying key conditioning factors and their spatial variability, this study contributes to more effective mitigation measures and the development of evidence-based policies to enhance resilience in high-risk areas.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"160 ","pages":"Article 105509"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838292","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}

引用次数: 0

Composite batholith assembly in a Paleoproterozoic continental arc – western Cauaburi Complex, northwestern Amazon Craton, Brazil 巴西亚马逊克拉通西北部古元古代大陆弧-西部Cauaburi杂岩复合岩基组合

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-04 DOI: 10.1016/j.jsames.2025.105507

Túlio A.A. Mendes , Matheus S. Simões , Marcelo E. Almeida , Raissa B. Mesquita

{"title":"Composite batholith assembly in a Paleoproterozoic continental arc – western Cauaburi Complex, northwestern Amazon Craton, Brazil","authors":"Túlio A.A. Mendes , Matheus S. Simões , Marcelo E. Almeida , Raissa B. Mesquita","doi":"10.1016/j.jsames.2025.105507","DOIUrl":"10.1016/j.jsames.2025.105507","url":null,"abstract":"<div><div>The Cauaburi Complex, northwestern Amazon Craton, represents the plutonic record of an Orosirian-Statherian magmatic arc (1.81–1.76 Ga). Despite the subsequent metamorphic events, primary features have been preserved, maintaining the magmatic characteristics of typical supra-subduction batholiths in the western portion of the Cauaburi Arc. The petrological characterization, field data, petrography, and lithochemistry reveal distinct magmatic facies in western Cauaburi Complex rocks. In a concentric pattern, tonalites hosted granodioritic to monzogranitic magmas, both with mafic microgranular enclaves. The magmatic reservoir remains active for approximately 45 Myr, and the magma replenishment and differentiation processes occur during the batholith's assembling. High-silica granites emerge from the magmatic mushes and differ from them in petrological terms. However, the crystallization age of 1763 ± 21 Ma coincides with the geochronological record of the calc-alkaline rocks nearby. Based on the analysis of the field relations and petrological process, we discuss how alkaline high-silica granites differentiate from calc-alkaline plutonic chambers in the final stage of the magmatism. In parallel with field relations, zircon geochronological records provide mineral-scale evidence of these magmatic processes, reflecting the zircon temperatures saturation data and interpretation.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105507"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792105","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}

引用次数: 0

Advancements in electroresistivity processing and data inversion for monitoring CO2 leakage: Insights from a field experiment and empirical data analysis using the pyGIMLi library 用于监测二氧化碳泄漏的电阻率处理和数据反演的进展：利用 pyGIMLi 库进行现场实验和经验数据分析的启示

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-04 DOI: 10.1016/j.jsames.2025.105512

Mauren E. Gaspar, Gustavo Heck, Fernando Hamerski, João Pedro T. Zielinski, Clarissa L. Melo

{"title":"Advancements in electroresistivity processing and data inversion for monitoring CO2 leakage: Insights from a field experiment and empirical data analysis using the pyGIMLi library","authors":"Mauren E. Gaspar, Gustavo Heck, Fernando Hamerski, João Pedro T. Zielinski, Clarissa L. Melo","doi":"10.1016/j.jsames.2025.105512","DOIUrl":"10.1016/j.jsames.2025.105512","url":null,"abstract":"<div><div>Monitoring CO<sub>2</sub> sequestration is critical for assessing the environmental integrity of Carbon Capture and Storage (CCS) projects. This study presents an innovative approach for monitoring CO<sub>2</sub> leakage in a shallow aquifer system in Viamão, Brazil, using electroresistivity tomography (ERT). During the experiment, 5–12.5 kg of CO<sub>2</sub> were injected daily into the subsurface, with geoelectrical sensors deployed to measure resistivity variations over time. Data processing and inversion were carried out using the pyGIMLi library, with a focus on optimizing the Lam regularization parameter to enhance model fitting. Results indicate that the Lam parameter plays a significant role in data quality, with increased discretization improving model accuracy. However, factors such as soil type, rainfall, and aquifer recharge rates also influenced the resistivity readings. Key findings include the importance of repeated data collection under stable climatic conditions, challenges posed by clay soils and heavy rainfall, and the necessity of high CO<sub>2</sub> injection rates for accurate detection of CO<sub>2</sub> migration. This study highlights the effectiveness of using open-source tools like pyGIMLi for CO<sub>2</sub> leakage monitoring, advancing the application of electroresistivity methods in environmental studies.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"159 ","pages":"Article 105512"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816856","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}

引用次数: 0

An oasis in Western Gondwana: A diverse Guadalupian paleoflora from South America 西冈瓦纳的绿洲：来自南美洲的瓜达卢普古植物群

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-04-02 DOI: 10.1016/j.jsames.2025.105508

Joseane Salau Ferraz , Joseline Manfroi , Arielli Fabrício Machado , William Vieira Gobo , Margot Guerra-Sommer , Felipe L. Pinheiro

{"title":"An oasis in Western Gondwana: A diverse Guadalupian paleoflora from South America","authors":"Joseane Salau Ferraz , Joseline Manfroi , Arielli Fabrício Machado , William Vieira Gobo , Margot Guerra-Sommer , Felipe L. Pinheiro","doi":"10.1016/j.jsames.2025.105508","DOIUrl":"10.1016/j.jsames.2025.105508","url":null,"abstract":"<div><div>The end of the Paleozoic Era was marked by intense climatic crises that not only annihilated much of the marine and terrestrial biodiversity but also acted as an evolutionary pressure, shaping the surviving lineages that thrived throughout the Mesozoic. The Guadalupian (Permian) is characterized by a gradual aridification, with the end of this epoch punctuated by a significant mass extinction event that profoundly impacted continental ecosystems. Guadalupian plant fossil localities are rare across Gondwana, usually preserving isolated material. In this study, we present a Guadalupian-aged outcrop in the southern Paraná Basin, Brazil, featuring a unique and remarkable taphoflora composed of a floristic association represented by different taxa: Lycopsida, Sphenopsida, Pteridospermae, Filicopsida, and Gymnospermae. This taphoflora not only represents an important record that broadens the paleoflora database of Gondwana during the Guadalupian but also demonstrates that arid conditions were not uniformly severe, allowing the persistence of forested humid latitudinal belts or small biodiversity hotspots, that served as sanctuaries for plant biodiversity of Gondwana in the lead-up to the Guadalupian extinction.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"158 ","pages":"Article 105508"},"PeriodicalIF":1.7,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777605","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}

引用次数: 0

Environment and agriculture in semi-arid Sandia basin of northeast Mexico during the late 20th - early 21st century drought 20世纪末至21世纪初干旱期间墨西哥东北部半干旱桑迪亚盆地的环境与农业

IF 1.7 4区地球科学

Journal of South American Earth Sciences Pub Date : 2025-03-29 DOI: 10.1016/j.jsames.2025.105506

Priyadarsi D. Roy , Logesh Natarajan , Lakshumanan Chokkalingam

{"title":"Environment and agriculture in semi-arid Sandia basin of northeast Mexico during the late 20th - early 21st century drought","authors":"Priyadarsi D. Roy , Logesh Natarajan , Lakshumanan Chokkalingam","doi":"10.1016/j.jsames.2025.105506","DOIUrl":"10.1016/j.jsames.2025.105506","url":null,"abstract":"<div><div>Changes in land use and land cover (Lu/Lc) and vegetation health, in the sub-decadal scale, estimated the possible impact of late 20th - early 21st century regional drought on the environment and agriculture of Sandia Basin (ca.226 km<sup>2</sup>) at the semi-arid northeast Mexico. Satellite-based Landsat Thematic Mapper (TM) and Operational Land Imager (OLI) data were assessed for the pre-drought (1985 and 1990 CE), drought (1995 and 2000 CE) and post-drought (2005, 2010 and 2015 CE) conditions. Loss of land with shrub in almost one-third of the basin (ca. 84.3 km<sup>2</sup>), ca. 87 % reduction in the very-high vegetation (NDVI>0.6) coverage and almost 3-fold expansion of areas with no vegetation (NDVI<0.1) reflected environmental changes during the drought. Deterioration in vegetation health was also reflected by 3-fold increase in the very-high drought severity (VCI: 0–10). Drought-associated reduction in agricultural activity was marked by ca.68.5 % shrinkage of cropland and ca.42 % expansion of fallow land in 2000 CE imagery compared to the pre-drought. Drought culmination led to more than 2-fold expansion of cropland in 2005 CE imagery. However, the very-high drought severity withstanding more than half of the basin (113–128 km<sup>2</sup>), even during the post-drought phases, showed lack of environmental recovery and it was consistent with a tendency of below-average precipitation as well as anthropogenic Lu/Lc modifications.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"158 ","pages":"Article 105506"},"PeriodicalIF":1.7,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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