Physics and Chemistry of the Earth最新文献

{"title":"Climate change and trends in europe and globally over the period 1970–2023","authors":"Mehmet Bilgili,&nbsp;Muhammet Tokmakci","doi":"10.1016/j.pce.2025.103928","DOIUrl":"10.1016/j.pce.2025.103928","url":null,"abstract":"<div><div>Accurate determination and monitoring of climate indicators are vital for understanding the true scope of climate change, planning effective adaptation and mitigation measures, ensuring the wise use of resources, and fostering public trust and support for necessary climate actions. This study focuses on the current status of climate change indicators and historical trends from 1970 to 2023. It provides a detailed comparative analysis of various climate indicators in Europe and globally, examining monthly and annual trends in key metrics. These indicators include air temperature (<em>T</em>), dew point temperature (<em>T</em>_<em>d</em>), wet bulb temperature (<em>T</em>_<em>w</em>), specific humidity (<em>q</em>), relative humidity (<em>RH</em>), water vapor partial pressure (<em>e</em>), dew point depression (<em>DPD</em>), air density (<em>ρ</em>), total column precipitable water (<em>TCPW</em>), and total precipitation (<em>TP</em>). The study's findings highlight significant changes in these climate indicators across Europe, revealing notable differences from global trends and offering detailed insights into regional variations in climate change impacts. <em>T</em>, <em>T</em>_<em>d</em>, <em>T</em>_<em>w</em>, <em>q</em>, <em>RH</em>, <em>e</em>, <em>DPD</em>, <em>ρ</em>, <em>TCPW</em>, and <em>TP</em> yearly anomalies relative to the 1991–2020 average for Europe in 2023 were found to be +1.0738 °C, +0.8497 °C, +0.8979 °C, +0.4338 g kg⁻¹, -0.9414 %rh, +0.6612 hPa, +0.2241 °C, −0.0048 kg m⁻³, +1.2030 kg m⁻² and +0.0413 <em>m</em>, respectively. However, the same climate indicators were computed globally as follows: +0.6008 °C, +0.4664 °C, +0.4919 °C, +0.2455 g kg⁻¹, -0.5316 %rh, +0.3806 hPa, +0.1343 °C, −0.0026 kg m⁻³, +0.8200 kg m⁻² and -0.0130 <em>m</em>.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103928"},"PeriodicalIF":3.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143821366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early Eocene paleoclimate and brine composition from fluid inclusion analysis of Bahadur Khel Salt, Upper Indus Basin, Pakistan","authors":"Asim Falak Naz ,&nbsp;Xiaowen Guo ,&nbsp;Chen Yong ,&nbsp;Saif ur Rehman ,&nbsp;Naveed Rehman ,&nbsp;Wakeel Hussain","doi":"10.1016/j.pce.2025.103913","DOIUrl":"10.1016/j.pce.2025.103913","url":null,"abstract":"<div><div>Fluid inclusions are crucial for reconstructing past climatic conditions because they provide information on evaporation rates and salinity variations over time. Fluid inclusion analysis of the Eocene Bahadur Khel Salt was carried out using thin sections, Raman spectroscopy, XRD, XRF, and microthermometry. Thin-section analysis indicated that the Bahadur Khel Salt predominantly comprises halite, with minor amounts of gypsum, anhydrite, and dolomite. Geochemical data indicate that halite primarily contains Na, Cl, O, Ca, Mg, Si, Al, Fe, Br, Sr, K, Zn, P, Ni, Pt, and S. Halite is not entirely pure, with an average content of 94.2 % in the primary crystals and 92.8 % in the secondary crystals. The presence of minor constituents such as calcite, ferrodolomite, ankerite, and anhydrite, as well as elements such as Mg, Ca, O, K, Si, and Al, suggests that the halite was formed from a combination of solutions with different compositions and was influenced by exposure to the atmosphere and meteoric water. Most primary crystals had a higher density than secondary crystals, indicating the presence of highly concentrated fluids. In the Bahadur Khel Salt, most inclusions are secondary and formed after deposition due to exposure to the atmosphere, which is influenced by tectonic activity and diagenetic processes. The homogenization temperature (Th) ranges from 5.8 °C to 24.3 °C, indicating varied seasonal transitions and hydrological processes, reflecting fluid entrapment under different paleoclimatic conditions. Lower Th values (5.8 °C) suggest cooler environments typical of winter or spring, indicating less evaporation and higher precipitation levels. In contrast, higher Th values (24.3 °C) reflect warmer summer conditions associated with increased evaporation and potentially drier periods.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103913"},"PeriodicalIF":3.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Projection of precipitation variability over the highlands of Yemen by statistical down-scaling for the period 2026–2100","authors":"Ali H. AL-Falahi ,&nbsp;Solomon H. Gebrechorkos ,&nbsp;Naeem Saddique ,&nbsp;Uwe Spank ,&nbsp;Christian Bernhofer","doi":"10.1016/j.pce.2025.103909","DOIUrl":"10.1016/j.pce.2025.103909","url":null,"abstract":"<div><div>Climate change significantly affects the management of environmental resources, particularly through changes in the amount and variability of local climate variables, such as precipitation. However, current projections from Global Climate Models (GCMs) are not directly applicable to local-scale impact modeling due to their coarse spatial resolution and inherent biases. To address this challenge, the Statistical Down-Scaling Model (SDSM) is employed to downscale daily precipitation, a crucial input for impact assessment models. This study focuses on the highlands of Yemen, a region highly vulnerable to climate change and precipitation variability. Due to limited and incomplete local climate data, we utilized the best available precipitation datasets, including the Climate Hazards Group Infra-Red Precipitation with Station data (CHIRPS), to fill in missing station data. Historical and future predictors derived from the National Center for Environmental Prediction (NCEP) reanalysis and the Canadian Earth System Model Phase 2 (CanESM2) were used to generate future precipitation scenarios, which were compared with the ensemble means from the Coupled Model Intercomparison Project Phase 5 (CMIP5) and the Coupled Model Intercomparison Project Phase 6 (CMIP6). We also used the Shared Socioeconomic Pathways (SSPs) scenarios, specifically SSP126 and SSP585, to evaluate potential future changes in precipitation. Results indicate a projected increase in seasonal precipitation during the 2030s (2026–2050), 2060s (2051–2075), and 2090s (2076–2100). The western highlands, including Al Mahwit, Rymah, and parts of Sana'a governorate, are expected to experience precipitation increases of up to 55 %. Under RCP2.6, the short rainy season (March–May) is projected to increase up to 14 %, while under RCP8.5, this increase could reach 24 %. The long rainy season (June–August) is expected to increase by 6 % under RCP2.6 and 27 % under RCP8.5. The dry season (December–February) could see increases of 18 % under RCP2.6 and 46 % under RCP8.5, while the autumn season (September–November) may experience a substantial rise of 61 %–101 %. At the annual timescale, precipitation is projected to increase up to 34 % higher than the baseline period (1991–2020) across the region. These projections indicate that the highlands of Yemen will experience wetter conditions in the 21st century. The findings provide valuable insights for developing adaptation strategies for water and environmental resource management, considering the potential future impacts of climate change in the region.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103909"},"PeriodicalIF":3.0,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pore structure and radon emission characteristics of shallow soil in the Golmud River Basin of the Qinghai‒Tibet Plateau","authors":"Xin Hu ,&nbsp;Qiang Sun ,&nbsp;Jinting Huang ,&nbsp;Jishi Geng ,&nbsp;Jie Wang","doi":"10.1016/j.pce.2025.103911","DOIUrl":"10.1016/j.pce.2025.103911","url":null,"abstract":"<div><div>The Qinghai-Tibet Plateau (QTP) has a high altitude, strong radiation and wide distribution of frozen soil, with typical alpine soil. Investigating the radon exhalation level of this distinctive soil is crucial for assessing the human settlement environment in the region. This study takes the Golmud River Basin as a case to study the pore structure and radon emission characteristics of shallow soil in a typical QTP area. Furthermore, explored the correlation between terrain, altitude, depth, and pore structure with radon emission rate. The key findings are as follows: In areas with severe salinization, soil exhibit the largest specific surface area and total pore volume, the mean values were 20.07 cm²/g and 0.05 cm³/g, respectively. As altitude increased, the specific surface area, total pore volume, and macropore fractal dimension <em>D</em>_a gradually rose, accompanied by significant expansion in macropore diameter. Soil at depths less than 20 cm demonstrated smaller specific surface area, total pore volume, and <em>D</em>_a. Conversely, depths exceeding 20 cm exhibited significantly larger specific surface area and total pore volume, albeit with a tendency for these metrics to decrease with increasing depth. Radon exhalation rate generally increased with burial depth and elevation. Notably, soil radon exhalation rate exhibited a positive correlation with micropore content and total pore content, with a stronger correlation observed with total porosity. While the source area displayed higher radon exhalation rates compared to the deposition area, the overall soil radon exhalation rate in the QTP was relatively lower than other global regions, the maximum is only 0.42 × 10⁻³ Bq/g·h. These research outcomes offer valuable insights for soil radiation risk assessment in the QTP.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103911"},"PeriodicalIF":3.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microplastics contamination in coastal environment of Southeast Asia: A systematic review","authors":"Natasha Arina ,&nbsp;Norfazrin Mohd Hanif ,&nbsp;Yet Yin Hee ,&nbsp;Murnira Othman ,&nbsp;Maggie Chel Gee Ooi ,&nbsp;Masni Mohd Ali ,&nbsp;Khairiatul Mardiana Jansar ,&nbsp;Mohd Talib Latif","doi":"10.1016/j.pce.2025.103910","DOIUrl":"10.1016/j.pce.2025.103910","url":null,"abstract":"<div><div>The recurrent issue of microplastic (MP) pollution in Southeast Asia has become a major challenge with serious repercussions on biodiversity, economy, and public health. Despite efforts to address the problem, a lack of thorough research on the sources, and distribution in the region impedes effective policymaking and intervention measures. This study aims to provide a comprehensive overview of the state of research on MPs in the coastal environment of Southeast Asia. We specifically addressed the following questions: What is the current composition and abundance of MPs existing in Southeast Asia's coastal areas, and what information gaps exist in the studies conducted in the coastal environment? Articles were retrieved using the Web of Science and Scopus databases, with publication dates ranging from 2019 to 2022. Our systematic review of 39 studies on MP pollution in the coastal environment of Southeast Asia reveals that MPs are prevalent in the region, with concentrations of up to 238,000 particles L⁻¹, &gt;200,000 particles kg⁻¹ and 40 particles m⁻² d⁻¹ in the coastal water, sediment and atmosphere, respectively. In addition, our study found that only a small proportion (n = 1) of all MP studies in the coastal environment addressed the composition of MPs in the atmosphere. Despite the significant abundance of MPs in the region, there has been a scarcity of comprehensive research on the sources and transport. Our findings highlight the critical need for more standardized sampling and more targeted research on the sources, distribution, and effect of MPs across Southeast Asia.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103910"},"PeriodicalIF":3.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time to diffuse the “ticking time bombs” of the Himalaya","authors":"Anshuman Bhardwaj ,&nbsp;Sheikh Nawaz Ali ,&nbsp;Lydia Sam ,&nbsp;Pratima Pandey","doi":"10.1016/j.pce.2025.103908","DOIUrl":"10.1016/j.pce.2025.103908","url":null,"abstract":"<div><div>During the past decade, a plethora of research articles have considerably advanced our understanding of the genesis, evolution, and hazard potential of the Himalayan glacial lakes. However, given the rapidly changing regional climate and land-use practices that exacerbate the risks, a research and policy shift towards adaptive management of glacial lakes, ranging from regulated siphoning to multistakeholder participation, is urgently required. In this perspective piece, we propose a Strengths, Weaknesses, Opportunities, and Threats (SWOT) framework, to highlight the key focus areas for future glacial lake outburst flood (GLOF) research and policymaking. The suggested approach is of proactive nature in influencing researchers and policymakers, and aims at integrating local socioeconomic and cultural contexts, while also assessing the hazard perception of communities. This also means that while the focus of this article is the Himalayan region, the ideas and the SWOT framework proposed here can easily be adapted for any other geographical region globally.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103908"},"PeriodicalIF":3.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geophysical insight on the formation of a barrier-beach-dune system: The case of the central sector of the Kyparissiakos Gulf coastal zone (Western Greece)","authors":"John D. Alexopoulos ,&nbsp;Serafeim E. Poulos ,&nbsp;Ioannis-Konstantinos Giannopoulos ,&nbsp;Vasileios Gkosios ,&nbsp;Spyridon Dilalos ,&nbsp;George Ghionis","doi":"10.1016/j.pce.2025.103912","DOIUrl":"10.1016/j.pce.2025.103912","url":null,"abstract":"<div><div>The present study investigates the formation and development of a coastal barrier associated with the recent evolution of the beach/dune system of the Kyparissiakos Gulf (SE Ionian Sea, central Mediterranean Sea) during the late phase of the Holocene (Flandrian) transgression. The study is based on the application of combined geophysical (ERT: Electrical Resistivity Tomography; GPR: Ground Penetrating Radar) and geotechnical (CPT: Cone Penetration Test; boreholes) techniques, supported by sedimentological (granulometric, mineralogical, palaeontological) analyses. According to the interpretation of the collected and processed data, the formation of the coastal barrier started during the transition between the fast and slow phase of the sea level rise (i.e. 6-7 ka BP), which coincides with an increased fluvial sediment inflow induced by the prevailing wetter climatic conditions (8000 - 3700 BP). The development of the coastal barrier most likely involves a progradational beach, associated with the formation of dunes that follow aggradational phases of coastal barrier and beach evolution. Based on ¹⁴C dating, the formation of the two younger dune ridges took place no earlier than 350 and 950 cal yr BP, respectively.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103912"},"PeriodicalIF":3.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An NMF-based qualified review of the trending topics in hydrology in the current era","authors":"Sila Ovgu Korkut ,&nbsp;Femin Yalcin ,&nbsp;Erman Ulker","doi":"10.1016/j.pce.2025.103907","DOIUrl":"10.1016/j.pce.2025.103907","url":null,"abstract":"<div><div>This study employs an AI-based approach using a non-negative matrix factorization tool, a kind of topic modeling method, to identify key research areas in hydrology. The observed hot topics were categorized into two main topic strands through a rigorous validity analysis which are “river basin” and “soil moisture.” Focusing on studies from January 1, 2022, to December 31, 2023, it examines the interconnected topics of \"river basin\" and \"soil moisture,\" narrowed down to 130 by expert review. These research items have been rigorously detailed in a tabular form for clarity and comprehensive understanding. Key findings indicate that 67 % of studies focus on “river basin,” 47 % on “soil moisture,” and 14 % on both, with “climate change” being a primary focus across these topics. The review highlights the increasing use of software, AI, and machine learning in hydrology, driven by digitalization. Optimization and forecasting are identified as prominent research areas, reflecting the ongoing relevance of climate crisis and water resource management in contemporary research.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103907"},"PeriodicalIF":3.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three parameter calculation method for dry rock modulus and its application in feasibility evaluation of time-lapse seismic in G oilfield","authors":"Shuchun Cao ,&nbsp;Xiangyang Cao ,&nbsp;Xiangsheng Bao ,&nbsp;Chunpeng Li ,&nbsp;Liyun Liu","doi":"10.1016/j.pce.2025.103904","DOIUrl":"10.1016/j.pce.2025.103904","url":null,"abstract":"<div><div>This study focuses on the offshore GE Oilfield with typical marine turbidite sandstone reservoirs and rich reserves. Improving production efficiency is crucial, and OBN-based TLS monitoring is the key means. However, the Macbeth method for calculating dry rock modulus in TLS rock physics theory has limited applicability. It's hard to accurately assess TLS performance in different porous reservoirs, severely restricting in-depth reservoir understanding. To address this issue, this study innovatively proposes a three-parameter dry rock modulus TP method that comprehensively considers porosity, density, and effective pressure, based on the petrophysical test data of 9 representative rock samples. Through rigorous comparative verification of data from low-, medium-, and high-porosity rock samples, the results show the TP method can be stably used under different porosity conditions, with broad universality and high prediction accuracy. It's incorporated into the Gassmann equation for G Oilfield TLS evaluation. A relational template of the CWI difference of 16 reservoir types considering porosity and shale content versus water saturation and pressure changes is constructed, and the corresponding changing laws are clarified. Meanwhile, factoring in bound water and residual oil saturation, a comparative analysis of TLS evaluations of four reservoir rock samples (R1, R2, R3, R4) is performed. It aims to assess the feasibility of TLS monitoring for each reservoir under different conditions, including maximum fluid replacement, single fluid replacement, and the combined impact of fluid replacement and pressure drop. The results will offer a more accurate and efficient method for G Oilfield's TLS monitoring, strongly supporting the enhancement of production efficiency.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103904"},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrochemical characteristics, groundwater nitrate sources and potential health risks in a typical alluvial plain of northwest China","authors":"Hao Liang ,&nbsp;Peiyue Li ,&nbsp;Vetrimurugan Elumalai ,&nbsp;Yan Tian ,&nbsp;Xiaomei Kou","doi":"10.1016/j.pce.2025.103903","DOIUrl":"10.1016/j.pce.2025.103903","url":null,"abstract":"<div><div>Due to anthropogenic pressures and the unpredictable impacts of climate change, groundwater quality issue has emerged as a critical concern. This study was carried out to investigate the evolving geochemical profile, identify the nitrate sources and transformation mechanisms, and assess the associated health hazards of phreatic groundwater in the Hua District, China. To achieve this goal, 65 and 37 phreatic water samples were collected in in October 2018 and March 2023, respectively, and analyzed for main water quality parameters and stable isotopes (δ¹⁸O-H₂O, δ²H-H₂O, δ¹⁵N-NO₃^-, and δ¹⁸O-NO₃^-). Piper diagram and ionic ratios were used for understanding the hydrochemical types and its evolution, stable isotopes were employed for tracing nitrate source, and human health risk assessment was also conducted to quantify the human health risk caused by exposure to groundwater NO₃⁻. The results showed that main ion composition of groundwater hydrochemistry is controlled by the rock weathering and dissolution of carbonates and sulfate minerals. The chemical types of groundwater present an evolution trend from SO₄•Cl-Ca•Mg to HCO₃-Ca•Mg. Severe nitrate pollution was detected particularly in the central and southern regions, with peak nitrate concentrations reaching 442 and 271 mg/L in 2018 and 2023, respectively. Nitrate sources include sewage, soil organic nitrogen, and fertilizers. A shift from single (M&amp;S) to multiple nitrate sources in groundwater was observed, with nitrification as the primary transformation process. The non-carcinogenic risks for children and adults declined from 0.245–3.455 to 0.039–2.586 and from 0.236–2.392 to 0.031–1.469, respectively, from 2018 to 2023. Additionally, these risky regions are shifting northward. Hence, individuals in the north-central part should heighten their vigilance towards groundwater quality to reduce the threats of nitrate pollution to human health.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"139 ","pages":"Article 103903"},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143629106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}