首页 > 最新文献

Journal of Hydrology最新文献

英文 中文
Vertical sediment stratification regulates dissolved nutrient dynamics and interface fluxes along the intertidal zone 垂直沉积物分层调节了潮间带的溶解营养物动力学和界面通量
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-19 DOI: 10.1016/j.jhydrol.2026.134980
Zhenyang Li , Yueqi Wang , Yashu Qi , Kai Xiao , Guangxuan Han , Hailong Li , Liang Liu , Dejuan Jiang , Xiaoying Zhang , Chunmiao Zheng
Sediment stratification is a ubiquitous feature in intertidal aquifers, yet its precise role in regulating dissolved nutrient dynamics remains poorly understood. This study examined two typical kinds of intertidal transects including the sandy beach and mudflat, each exhibiting distinct sediment stratification. We analyzed the multi-depth distribution patterns of dissolved nutrients (nitrogen, phosphorus, and silicon) and carbon in intertidal groundwater. We also identified the key drivers using stable isotope tracers (δ15N-NO3 and δ18O-NO3) and multivariate statistics, and quantified the interface fluxes to the coastal ocean. The findings indicated that the distribution patterns of nutrients and carbon between fine- and coarse-grained sediments in both transects were synthetically influenced by hydrological dynamics and biogeochemical reactions. In the sandy beach, groundwater composition transitioned from being NO3-dominated in the deep coarse-grained sediments, where attenuation occurred via denitrification, to NH4+-dominated in the surface fine-grained sediments due to organic matter mineralization. In the mudflat, organic-rich sediments and low water exchange rates favored NH4+ dominance, with fine-grained sediments accumulating high concentrations of NH4+, PO43−, and DSi in groundwater. Moreover, the sandy beach served as hotspots for groundwater discharge, delivering nutrient and dissolved carbon fluxes up to two orders of magnitude higher than the mudflat. The presence of a surface fine-grained sediments enhanced the export of groundwater-derived NH4+ and DIC, potentially exacerbating coastal eutrophication and acidification. These findings demonstrate that sediment stratification fundamentally alters the composition and flux magnitude of nutrients and carbon discharged into coastal waters, thereby influencing coastal solute budgets.
沉积物分层是潮间带含水层中普遍存在的特征,但其在调节溶解营养动态中的确切作用仍然知之甚少。本研究考察了两种典型的潮间带样带,包括沙滩和泥滩,每种样带都表现出不同的沉积物分层。分析了潮间带地下水中溶解营养物(氮、磷、硅)和碳的多深度分布规律。我们还利用稳定同位素示踪剂(δ15N-NO3−和δ18O-NO3−)和多元统计方法确定了关键驱动因素,并量化了向沿海海洋的界面通量。结果表明,两样带细粒和粗粒沉积物中营养物质和碳的分布格局受到水文动力学和生物地球化学反应的综合影响。在沙质滩,地下水组成由深层粗粒沉积物中NO3−为主(通过反硝化作用发生衰减)向表层细粒沉积物中NH4+为主(由于有机质矿化作用)转变。在泥滩中,富有机质沉积物和低水交换率有利于NH4+优势,细粒沉积物在地下水中积累了高浓度的NH4+、PO43−和DSi。此外,沙质海滩是地下水排放的热点,提供的养分和溶解碳通量比泥滩高两个数量级。表层细粒沉积物的存在增加了地下水衍生NH4+和DIC的输出,可能加剧沿海富营养化和酸化。这些发现表明,沉积物分层从根本上改变了向沿海水域排放的营养物和碳的组成和通量大小,从而影响了沿海的溶质收支。
{"title":"Vertical sediment stratification regulates dissolved nutrient dynamics and interface fluxes along the intertidal zone","authors":"Zhenyang Li ,&nbsp;Yueqi Wang ,&nbsp;Yashu Qi ,&nbsp;Kai Xiao ,&nbsp;Guangxuan Han ,&nbsp;Hailong Li ,&nbsp;Liang Liu ,&nbsp;Dejuan Jiang ,&nbsp;Xiaoying Zhang ,&nbsp;Chunmiao Zheng","doi":"10.1016/j.jhydrol.2026.134980","DOIUrl":"10.1016/j.jhydrol.2026.134980","url":null,"abstract":"<div><div>Sediment stratification is a ubiquitous feature in intertidal aquifers, yet its precise role in regulating dissolved nutrient dynamics remains poorly understood. This study examined two typical kinds of intertidal transects including the sandy beach and mudflat, each exhibiting distinct sediment stratification. We analyzed the multi-depth distribution patterns of dissolved nutrients (nitrogen, phosphorus, and silicon) and carbon in intertidal groundwater. We also identified the key drivers using stable isotope tracers (δ<sup>15</sup>N-NO<sub>3</sub><sup>−</sup> and δ<sup>18</sup>O-NO<sub>3</sub><sup>−</sup>) and multivariate statistics, and quantified the interface fluxes to the coastal ocean. The findings indicated that the distribution patterns of nutrients and carbon between fine- and coarse-grained sediments in both transects were synthetically influenced by hydrological dynamics and biogeochemical reactions. In the sandy beach, groundwater composition transitioned from being NO<sub>3</sub><sup>−</sup>-dominated in the deep coarse-grained sediments, where attenuation occurred via denitrification, to NH<sub>4</sub><sup>+</sup>-dominated in the surface fine-grained sediments due to organic matter mineralization. In the mudflat, organic-rich sediments and low water exchange rates favored NH<sub>4</sub><sup>+</sup> dominance, with fine-grained sediments accumulating high concentrations of NH<sub>4</sub><sup>+</sup>, PO<sub>4</sub><sup>3−</sup>, and DSi in groundwater. Moreover, the sandy beach served as hotspots for groundwater discharge, delivering nutrient and dissolved carbon fluxes up to two orders of magnitude higher than the mudflat. The presence of a surface fine-grained sediments enhanced the export of groundwater-derived NH<sub>4</sub><sup>+</sup> and DIC, potentially exacerbating coastal eutrophication and acidification. These findings demonstrate that sediment stratification fundamentally alters the composition and flux magnitude of nutrients and carbon discharged into coastal waters, thereby influencing coastal solute budgets.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 134980"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Retrieval of snow depth using synthetic aperture radar: past, current, and future 利用合成孔径雷达反演雪深:过去、现在和未来
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-02-07 DOI: 10.1016/j.jhydrol.2026.135103
Zhen Li , Haiwei Qiao , Ping Zhang , Yanan Bai , Huadong Hu
Snow is one of the most dynamic factors in the climate system. In recent years, as climate change has intensified, the distribution of the global snow cover and the timing of snowmelt have changed, seriously affecting the hydrological cycle, ecosystems, carbon balance, and human activities. Snow depth, as a key parameter for measuring snow changes, plays a crucial role in water storage estimation, disaster prediction, and research on global sustainability. Considering the limited spatial representativeness of ground observations and the insufficient spatial resolution of passive microwave remote sensing, synthetic aperture radar (SAR) offers a viable solution for the superior precision and fine-scale retrieval of spatiotemporally continuous snow depth. This paper begins with the interaction between SAR signals and snow, reviewing different types of snow backscattering models and surface scattering models. Then, the SAR data for snow depth retrieval are outlined. Thirdly, snow depth retrieval methods based on polarimetric SAR (PolSAR), interferometric SAR (InSAR), polarimetric interferometric SAR (PolInSAR), and tomographic SAR (TomoSAR) techniques in the last two decades are summarized. Finally, the current opportunities and challenges are envisioned to provide reliable references for future studies.
雪是气候系统中最具动态的因子之一。近年来,随着气候变化的加剧,全球积雪分布和融雪时间发生了变化,严重影响了水文循环、生态系统、碳平衡和人类活动。雪深作为测量积雪变化的关键参数,在水量估算、灾害预测、全球可持续性研究等方面具有重要作用。考虑到地面观测的空间代表性有限和被动微波遥感的空间分辨率不足,合成孔径雷达(SAR)为高精度、精细尺度的时空连续雪深反演提供了可行的解决方案。本文从SAR信号与雪的相互作用入手,综述了不同类型的雪后向散射模型和地面散射模型。然后,概述了积雪深度检索的SAR数据。第三,总结了近20年来基于偏振SAR (PolSAR)、干涉SAR (InSAR)、偏振干涉SAR (PolInSAR)和层析SAR (TomoSAR)技术的雪深反演方法。最后,展望当前的机遇和挑战,为今后的研究提供可靠的参考。
{"title":"Retrieval of snow depth using synthetic aperture radar: past, current, and future","authors":"Zhen Li ,&nbsp;Haiwei Qiao ,&nbsp;Ping Zhang ,&nbsp;Yanan Bai ,&nbsp;Huadong Hu","doi":"10.1016/j.jhydrol.2026.135103","DOIUrl":"10.1016/j.jhydrol.2026.135103","url":null,"abstract":"<div><div>Snow is one of the most dynamic factors in the climate system. In recent years, as climate change has intensified, the distribution of the global snow cover and the timing of snowmelt have changed, seriously affecting the hydrological cycle, ecosystems, carbon balance, and human activities. Snow depth, as a key parameter for measuring snow changes, plays a crucial role in water storage estimation, disaster prediction, and research on global sustainability. Considering the limited spatial representativeness of ground observations and the insufficient spatial resolution of passive microwave remote sensing, synthetic aperture radar (SAR) offers a viable solution for the superior precision and fine-scale retrieval of spatiotemporally continuous snow depth. This paper begins with the interaction between SAR signals and snow, reviewing different types of snow backscattering models and surface scattering models. Then, the SAR data for snow depth retrieval are outlined. Thirdly, snow depth retrieval methods based on polarimetric SAR (PolSAR), interferometric SAR (InSAR), polarimetric interferometric SAR (PolInSAR), and tomographic SAR (TomoSAR) techniques in the last two decades are summarized. Finally, the current opportunities and challenges are envisioned to provide reliable references for future studies.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"669 ","pages":"Article 135103"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146138399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Imputation of continuous missing values in water quality data using a temporal embedding-based self-attention variational autoencoder 基于时间嵌入的自关注变分自编码器在水质数据中连续缺失值的输入
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-12 DOI: 10.1016/j.jhydrol.2026.134937
Xinghan Xu , Lei Hu , Xingyi Miao , Peng Xiao , Xiaohui Yan , Jianwei Liu
Missing values in water quality data (WQD), caused by sensor malfunctions, communication failures, and environmental disturbances, undermine the reliability of conventional imputation methods. To address these challenges, we propose the Temporal Embedding-based Self-Attention t-distributed Variational Autoencoder (TE-SAVAE-St), a model designed for robust and temporally consistent data reconstruction. The model incorporates a Student’s-t prior to handle outliers, temporal embeddings (TE) to capture chronological patterns, and multi-head self-attention (MSA) to model long-term dependencies and inter-variable correlations. Extensive experiments on real-world WQD datasets show that TE-SAVAE-St outperforms ten baseline methods under various missing data scenarios, reducing RMSE by 11.8% and SMAPE by 23.6% compared to state-of-the-art models. Ablation studies confirm the complementary benefits of TE, MSA, and Student’s-t components. Additionally, time complexity analysis demonstrates that TE-SAVAE-St achieves an optimal balance between computational efficiency and imputation accuracy, making it suitable for real-time and large-scale monitoring applications. Overall, TE-SAVAE-St offers a domain-aware framework for the accurate reconstruction of incomplete WQD, supporting continuous environmental monitoring.
由传感器故障、通信故障和环境干扰引起的水质数据(WQD)缺失值破坏了传统估算方法的可靠性。为了解决这些挑战,我们提出了基于时间嵌入的自关注t分布变分自编码器(TE-SAVAE-St),这是一个设计用于鲁棒和时间一致数据重建的模型。该模型结合了处理异常值的Student 's-t先验、捕捉时间模式的时间嵌入(TE)和模拟长期依赖关系和变量间相关性的多头自我注意(MSA)。在真实WQD数据集上的大量实验表明,在各种缺失数据场景下,TE-SAVAE-St优于10种基线方法,与最先进的模型相比,RMSE降低了11.8%,SMAPE降低了23.6%。消融研究证实了TE、MSA和Student 's-t组件的互补益处。此外,时间复杂度分析表明,TE-SAVAE-St在计算效率和输入精度之间实现了最佳平衡,适合实时和大规模监测应用。总的来说,TE-SAVAE-St为不完整WQD的精确重建提供了一个领域感知框架,支持持续的环境监测。
{"title":"Imputation of continuous missing values in water quality data using a temporal embedding-based self-attention variational autoencoder","authors":"Xinghan Xu ,&nbsp;Lei Hu ,&nbsp;Xingyi Miao ,&nbsp;Peng Xiao ,&nbsp;Xiaohui Yan ,&nbsp;Jianwei Liu","doi":"10.1016/j.jhydrol.2026.134937","DOIUrl":"10.1016/j.jhydrol.2026.134937","url":null,"abstract":"<div><div>Missing values in water quality data (WQD), caused by sensor malfunctions, communication failures, and environmental disturbances, undermine the reliability of conventional imputation methods. To address these challenges, we propose the Temporal Embedding-based Self-Attention t-distributed Variational Autoencoder (TE-SAVAE-St), a model designed for robust and temporally consistent data reconstruction. The model incorporates a Student’s-t prior to handle outliers, temporal embeddings (TE) to capture chronological patterns, and multi-head self-attention (MSA) to model long-term dependencies and inter-variable correlations. Extensive experiments on real-world WQD datasets show that TE-SAVAE-St outperforms ten baseline methods under various missing data scenarios, reducing RMSE by 11.8% and SMAPE by 23.6% compared to state-of-the-art models. Ablation studies confirm the complementary benefits of TE, MSA, and Student’s-t components. Additionally, time complexity analysis demonstrates that TE-SAVAE-St achieves an optimal balance between computational efficiency and imputation accuracy, making it suitable for real-time and large-scale monitoring applications. Overall, TE-SAVAE-St offers a domain-aware framework for the accurate reconstruction of incomplete WQD, supporting continuous environmental monitoring.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 134937"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145957165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
The impact of rainfall characteristics on combined sewer overflows in wet weather 潮湿天气下降雨特征对合流下水道溢流的影响
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-12 DOI: 10.1016/j.jhydrol.2026.134951
Hao Wang , Zijian Wang , Pengfei Zeng , Zilong Liu , Bin Chen , Jinjun Zhou
Combined sewer overflows (CSO) pose risks to both water quality and public health. However, the impact of varying rainfall characteristics on CSO remains unclear. This study aims to assess and analyze the correlations between CSO and rainfall characteristics, specifically rainfall depth, duration, and the proportion of rainfall occurring during peak periods. The objective is to identify and elucidate the impacts of each main rainfall characteristic on the frequency of CSO. To conduct this analysis, rainfall data spanning 71 years were divided into 1,435 rainfall events and categorized into five representative rainfall patterns based on their temporal distribution. A hydraulic model of sewer network was employed to simulate the CSO results under different rainfall patterns. An indicator termed “rainfall-CSO contribution rate” was introduced to reflect the impact of rainfall on CSO. The neural network method was utilized to establish a relationship model between rainfall characteristics and rainfall-CSO contribution rate (R2 > 0.94). Sensitivity analysis and model visualization techniques were used to reveal the relationship between rainfall characteristics and rainfall-CSO contribution rate. Significant differences in contribution rates across rainfall patterns were observed (p = 0.012), indicating a strong association with rainfall characteristics. Specifically, rainfall patterns with a higher proportion of peak period precipitation correspond to greater CSO contribution rates. Within each rainfall pattern, rainfall depth was identified as the most critical factor affecting the CSO contribution rate, followed by rainfall duration, with average sensitivity indices of 0.580 and 0.274, respectively. The peak-period rainfall ratio had a minimal impact on the results, with an average sensitivity index of just 0.024. Furthermore, the study noted that, variations in CSO contribution rates across different patterns intensified with increasing rainfall depth, while the impact of rainfall duration diminished with longer durations. This research provides a methodical approach for quantitatively analyzing the relationship between rainfall characteristics and CSO contribution rates, facilitating rapid assessments of CSO conditions and informing urban planning and drainage management decisions.
合流下水道溢流对水质和公众健康都构成威胁。然而,不同的降雨特征对CSO的影响尚不清楚。本研究旨在评估和分析CSO与降雨特征的相关性,特别是降雨深度、持续时间和高峰期间降雨的比例。目的是确定和阐明每一个主要降雨特征对CSO频率的影响。为了进行分析,将71 年的降雨数据分为1435个降雨事件,并根据其时间分布将其分为5种具有代表性的降雨模式。采用管网水工模型对不同降雨模式下的CSO结果进行了模拟。引入了一个称为“降雨-中央社会组织贡献率”的指标,以反映降雨对中央社会组织的影响。利用神经网络方法建立降雨特征与降雨量- cso贡献率的关系模型(R2 >; 0.94)。利用敏感性分析和模型可视化技术揭示了降雨特征与降雨量- cso贡献率之间的关系。不同降雨模式的贡献率存在显著差异(p = 0.012),表明与降雨特征有很强的关联。具体而言,峰值降水比例较高的降水模式对应于较大的CSO贡献率。在各降水模式中,降雨深度是影响CSO贡献率的最关键因素,其次是降雨持续时间,平均敏感性指数分别为0.580和0.274。峰值时期降雨比对结果的影响最小,平均敏感性指数仅为0.024。此外,研究还指出,随着降雨深度的增加,不同模式间CSO贡献率的变化会加剧,而降雨持续时间的影响则会随着持续时间的延长而减弱。本研究为定量分析降雨特征与CSO贡献率之间的关系提供了一种系统的方法,有助于快速评估CSO状况,为城市规划和排水管理决策提供信息。
{"title":"The impact of rainfall characteristics on combined sewer overflows in wet weather","authors":"Hao Wang ,&nbsp;Zijian Wang ,&nbsp;Pengfei Zeng ,&nbsp;Zilong Liu ,&nbsp;Bin Chen ,&nbsp;Jinjun Zhou","doi":"10.1016/j.jhydrol.2026.134951","DOIUrl":"10.1016/j.jhydrol.2026.134951","url":null,"abstract":"<div><div>Combined sewer overflows (CSO) pose risks to both water quality and public health. However, the impact of varying rainfall characteristics on CSO remains unclear. This study aims to assess and analyze the correlations between CSO and rainfall characteristics, specifically rainfall depth, duration, and the proportion of rainfall occurring during peak periods. The objective is to identify and elucidate the impacts of each main rainfall characteristic on the frequency of CSO. To conduct this analysis, rainfall data spanning 71 years were divided into 1,435 rainfall events and categorized into five representative rainfall patterns based on their temporal distribution. A hydraulic model of sewer network was employed to simulate the CSO results under different rainfall patterns. An indicator termed “rainfall-CSO contribution rate” was introduced to reflect the impact of rainfall on CSO. The neural network method was utilized to establish a relationship model between rainfall characteristics and rainfall-CSO contribution rate (R<sup>2</sup> &gt; 0.94). Sensitivity analysis and model visualization techniques were used to reveal the relationship between rainfall characteristics and rainfall-CSO contribution rate. Significant differences in contribution rates across rainfall patterns were observed (p = 0.012), indicating a strong association with rainfall characteristics. Specifically, rainfall patterns with a higher proportion of peak period precipitation correspond to greater CSO contribution rates. Within each rainfall pattern, rainfall depth was identified as the most critical factor affecting the CSO contribution rate, followed by rainfall duration, with average sensitivity indices of 0.580 and 0.274, respectively. The peak-period rainfall ratio had a minimal impact on the results, with an average sensitivity index of just 0.024. Furthermore, the study noted that, variations in CSO contribution rates across different patterns intensified with increasing rainfall depth, while the impact of rainfall duration diminished with longer durations. This research provides a methodical approach for quantitatively analyzing the relationship between rainfall characteristics and CSO contribution rates, facilitating rapid assessments of CSO conditions and informing urban planning and drainage management decisions.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 134951"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145957292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Towards cooperation on transboundary rivers: achieving a win–win balance between upstream hydropower generation and downstream water demand under climate change 走向跨界河流合作:实现气候变化下上下游水电需求的共赢
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-02-10 DOI: 10.1016/j.jhydrol.2026.135111
Tesfalem Abraham , Tunde Olarinoye , Andreas Hartmann , Harrie-Jan Hendricks Franssen , Yan Liu
Transboundary river management is critical for international relations, sustainable energy development, and ecosystem management. Hydropower development, while meeting downstream water demand, is crucial for fostering cooperation among countries sharing water resources. However, addressing this challenge under the context of climate change poses significant complexities. This study investigates the cooperation regarding hydropower production and water releases under the potential impact of climate change. We project future streamflow by the calibrated HBV hydrological model in three transboundary rivers originating from Ethiopia: the Upper Blue Nile (UBN), Omo, and Tekeze rivers. Subsequently, we compute the hydropower potential (maximum hydropower energy within a specific period) by optimizing water release policies using the adapted ’Reservoir’ R package. The hydropower potential and water release are analyzed based on 11 scenarios of water releases ranging from favoring the upstream country (Scenario 1) to benefiting downstream countries (Scenario 11) for the three example dams on the studied transboundary rivers: the Grand Ethiopian Renaissance Dam (GERD), Omo-Gibe III, and Tekeze dams. Our focus lies in identifying the cooperation ranges that provide optimal hydropower in the upstream and water release to the downstream among the varying water release policies within this scenario spectrum. The findings indicate that within an appropriate range for the minimum monthly water release threshold, the hydropower potential for the three study sites only has a small decrease, while the water release to downstream, especially for the driest month, can be 1.14–2.45 times larger compared to no water release constraints. For GERD and Omo-Gibe III, maintaining the monthly water release threshold of 30%-50% of the monthly flow is assumed to define the cooperation range in the historical periods. However, for Tekeze, the cooperation range is from 20% to 40% of the monthly water release. Due to climate change, the cooperation range for GERD and Omo-Gibe III is projected to decrease to 20–30% in future periods, whereas no significant impact is expected for Tekeze. The study reveals that future energy production of the hydropower dams on the transboundary rivers are influenced by the monthly minimum water release threshold, underscoring the need for adaptive cooperative strategies for both upstream and downstream countries in the face of climate change.
跨界河流管理对国际关系、可持续能源发展和生态系统管理至关重要。水电开发在满足下游用水需求的同时,对促进水资源共享国之间的合作至关重要。然而,在气候变化的背景下应对这一挑战非常复杂。本研究探讨了气候变化潜在影响下的水电生产与放水合作。我们通过校准的HBV水文模型预测了来自埃塞俄比亚的三条跨界河流的未来流量:上青尼罗河(UBN)、Omo和Tekeze河。随后,我们通过使用改编的“水库”R包优化放水政策来计算水电潜力(特定时期内的最大水电能量)。本研究基于11种放水情景分析了水电潜力和放水情况,从有利于上游国家(情景1)到有利于下游国家(情景11),涉及所研究的跨界河流上的三个示例水坝:大埃塞俄比亚复兴大坝(GERD)、Omo-Gibe III和Tekeze水坝。我们的重点在于确定在该情景范围内的不同放水政策中,为上游提供最佳水电和向下游放水的合作范围。结果表明,在适当的最小月放水量阈值范围内,3个研究点的水电潜力仅略有下降,而向下游放水量,特别是在最干旱月份,可比无放水量约束时增加1.14-2.45倍。对于GERD和Omo-Gibe III,假设维持月水量30%-50%的月放水阈值来定义历史时期的合作范围。然而,对于Tekeze来说,合作范围是每月放水量的20%到40%。由于气候变化,GERD和Omo-Gibe III的合作范围预计将在未来一段时间内减少到20-30%,而Tekeze预计不会受到重大影响。研究表明,跨界河流上的水电大坝未来的能源生产受到每月最低放水量阈值的影响,强调了面对气候变化,上下游国家都需要适应性合作战略。
{"title":"Towards cooperation on transboundary rivers: achieving a win–win balance between upstream hydropower generation and downstream water demand under climate change","authors":"Tesfalem Abraham ,&nbsp;Tunde Olarinoye ,&nbsp;Andreas Hartmann ,&nbsp;Harrie-Jan Hendricks Franssen ,&nbsp;Yan Liu","doi":"10.1016/j.jhydrol.2026.135111","DOIUrl":"10.1016/j.jhydrol.2026.135111","url":null,"abstract":"<div><div>Transboundary river management is critical for international relations, sustainable energy development, and ecosystem management. Hydropower development, while meeting downstream water demand, is crucial for fostering cooperation among countries sharing water resources. However, addressing this challenge under the context of climate change poses significant complexities. This study investigates the cooperation regarding hydropower production and water releases under the potential impact of climate change. We project future streamflow by the calibrated HBV hydrological model in three transboundary rivers originating from Ethiopia: the Upper Blue Nile (UBN), Omo, and Tekeze rivers. Subsequently, we compute the hydropower potential (maximum hydropower energy within a specific period) by optimizing water release policies using the adapted ’Reservoir’ R package. The hydropower potential and water release are analyzed based on 11 scenarios of water releases ranging from favoring the upstream country (Scenario 1) to benefiting downstream countries (Scenario 11) for the three example dams on the studied transboundary rivers: the Grand Ethiopian Renaissance Dam (GERD), Omo-Gibe III, and Tekeze dams. Our focus lies in identifying the cooperation ranges that provide optimal hydropower in the upstream and water release to the downstream among the varying water release policies within this scenario spectrum. The findings indicate that within an appropriate range for the minimum monthly water release threshold, the hydropower potential for the three study sites only has a small decrease, while the water release to downstream, especially for the driest month, can be 1.14–2.45 times larger compared to no water release constraints. For GERD and Omo-Gibe III, maintaining the monthly water release threshold of 30%-50% of the monthly flow is assumed to define the cooperation range in the historical periods. However, for Tekeze, the cooperation range is from 20% to 40% of the monthly water release. Due to climate change, the cooperation range for GERD and Omo-Gibe III is projected to decrease to 20–30% in future periods, whereas no significant impact is expected for Tekeze. The study reveals that future energy production of the hydropower dams on the transboundary rivers are influenced by the monthly minimum water release threshold, underscoring the need for adaptive cooperative strategies for both upstream and downstream countries in the face of climate change.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"669 ","pages":"Article 135111"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Geochemical dynamics and colloidal transfer of major and trace elements in the Hers-Mort − Girou watershed: distinction between natural and anthropogenic signatures evidenced by REE anomalies Hers-Mort - Girou流域主要和微量元素的地球化学动力学和胶体转移:由稀土异常证明的自然和人为特征的区别
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-20 DOI: 10.1016/j.jhydrol.2026.134981
Baptiste Alran , Eva Schreck , Rémy Berrabah , Oleg S. Pokrovsky , Aubin Yettou , Jérôme Viers
Small watersheds are highly sensitive to anthropization, which deeply alters elemental biogeochemical cycles. This study focuses on the Hers-Mort and Girou watersheds near Toulouse (SW France), originating in the rural Lauragais region. A sampling campaign in January 2025 combined laboratory ultrafiltration (0.22 μm, 0.025 μm, 3 kDa) with measurements of physicochemical parameters (conductivity, pH, alkalinity) and elemental concentrations (DOC, anions, major cations, and trace elements).
Results reveal a clear distinction between natural and anthropogenic signals. Linear relationships between carbonates, nitrates, and Ca–Mg highlight the dominant role of lithology, with carbonate dissolution naturally supplying major cations, further enhanced by nitrates. Ultrafiltration showed that most elements occur in the labile low-molecular-weight <3 kDa (LMW <3 kDa) fraction, indicating high potential bioavailability and little downstream variation in DOC, Fe, Mn, Cu, and As.
Conversely, Zn and Gd displayed strong co-variation in their colloidal patterns, with the <3 kDa fraction increasing downstream in parallel with urbanization, reaching up to 80 % in the most impacted areas. These elements thus represent robust tracers of anthropogenic influence. Rare Earth Element (REE) patterns in headwaters were controlled by molassic lithology, whereas downstream sections showed pronounced positive Gd anomalies (0.89–25) and systematic LREE depletion with HREE enrichment. Anthropogenic Gd accounted for 10–90 % of total Gd, evidencing clear artificial inputs and the progressive shift from natural to anthropogenic geochemical dynamics.
小流域对人类活动高度敏感,人类活动深刻地改变了元素生物地球化学循环。本研究的重点是图卢兹(法国西南部)附近的Hers-Mort和Girou流域,起源于农村Lauragais地区。2025年1月的采样活动结合了实验室超滤(0.22 μm, 0.025 μm, 3 kDa)和物理化学参数(电导率,pH值,碱度)和元素浓度(DOC,阴离子,主要阳离子和微量元素)的测量。结果揭示了自然和人为信号之间的明显区别。碳酸盐岩、硝酸盐和Ca-Mg之间的线性关系突出了岩性的主导作用,碳酸盐岩的溶解自然提供了主要阳离子,硝酸盐进一步增强了阳离子的作用。超滤表明,大多数元素都出现在不稳定的低分子量3 kDa (LMW <3 kDa)馏分中,表明生物利用度高,DOC、Fe、Mn、Cu和As的下游变化不大。相反,Zn和Gd的胶体形态表现出较强的共变异性,随着城市化进程的推进,Zn和Gd的3 kDa分数向下游增加,在受影响最严重的地区最高可达80%。因此,这些元素是人类活动影响的有力示踪剂。上游地区稀土元素(REE)分布受摩尔系岩性控制,下游地区呈现明显的正Gd异常(0.89-25),且存在轻稀土(LREE)亏缺、重稀土(HREE)富集的现象。人为Gd占总Gd的10 ~ 90%,表明人工输入明显,地球化学动力学由自然向人为的逐渐转变。
{"title":"Geochemical dynamics and colloidal transfer of major and trace elements in the Hers-Mort − Girou watershed: distinction between natural and anthropogenic signatures evidenced by REE anomalies","authors":"Baptiste Alran ,&nbsp;Eva Schreck ,&nbsp;Rémy Berrabah ,&nbsp;Oleg S. Pokrovsky ,&nbsp;Aubin Yettou ,&nbsp;Jérôme Viers","doi":"10.1016/j.jhydrol.2026.134981","DOIUrl":"10.1016/j.jhydrol.2026.134981","url":null,"abstract":"<div><div>Small watersheds are highly sensitive to anthropization, which deeply alters elemental biogeochemical cycles. This study focuses on the Hers-Mort and Girou watersheds near Toulouse (SW France), originating in the rural Lauragais region. A sampling campaign in January 2025 combined laboratory ultrafiltration (0.22 μm, 0.025 μm, 3 kDa) with measurements of physicochemical parameters (conductivity, pH, alkalinity) and elemental concentrations (DOC, anions, major cations, and trace elements).</div><div>Results reveal a clear distinction between natural and anthropogenic signals. Linear relationships between carbonates, nitrates, and Ca–Mg highlight the dominant role of lithology, with carbonate dissolution naturally supplying major cations, further enhanced by nitrates. Ultrafiltration showed that most elements occur in the labile low-molecular-weight &lt;3 kDa (LMW &lt;3 kDa) fraction, indicating high potential bioavailability and little downstream variation in DOC, Fe, Mn, Cu, and As.</div><div>Conversely, Zn and Gd displayed strong co-variation in their colloidal patterns, with the &lt;3 kDa fraction increasing downstream in parallel with urbanization, reaching up to 80 % in the most impacted areas. These elements thus represent robust tracers of anthropogenic influence. Rare Earth Element (REE) patterns in headwaters were controlled by molassic lithology, whereas downstream sections showed pronounced positive Gd anomalies (0.89–25) and systematic LREE depletion with HREE enrichment. Anthropogenic Gd accounted for 10–90 % of total Gd, evidencing clear artificial inputs and the progressive shift from natural to anthropogenic geochemical dynamics.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 134981"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146015014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Comparative analysis of GAMLSS modeling approaches for nonstationary runoff dynamics in the Yellow River Basin of China 黄河流域非平稳径流动态的GAMLSS模拟方法比较分析
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-29 DOI: 10.1016/j.jhydrol.2026.135048
Ben Niu , Yi Li , Yurui Fan , Lei Gong , Lei Wang , Taishan Wang
Quantifying the driving effects of climate change and human activities on nonstationary runoff dynamics is essential. However, the systematic assessments of nonstationary characteristics and their multiple driving mechanisms at the basin scale remain insufficient. This study compared two Generalized Additive Model for Location, Scale, and Shape (GAMLSS) modeling approaches–Continuous-series modeling (Mode1) and monthly-segmented modeling (Mode2)–to analyze the hydrological nonstationarity characteristics of the Yellow River Basin in China and elucidate the driving mechanisms of runoff processes by incorporating covariates of time, circulation, climate, and human factors. The results indicated that: (1) Taking time as a covariate, Mode2 significantly enhanced model robustness by isolating seasonal dynamics. Mode2 raised the average correlation of the location parameter (μ) with the monthly runoff series to R = 0.82 (range 0.70–0.90), a 30–50% increase over Mode1. Furthermore, the nonstationary standardized runoff index (NSRI) aligned more accurately with actual hydrological fluctuations. (2) Taking circulation indices as covariates, circulation indices (AMO, PDO and NINO3) predominantly governed large-scale hydrological trends, with PDO exerting a more pronounced regulatory effect on extreme events in the downstream region under Mode2. (3) The climate-human composite-driven model had the best fitting effect on runoff, particularly at lower timescales (1-, 3-, and 6-month scales) in the middle and lower reaches, where the interactions among total precipitation (TP), snowmelt (SMT), and soil water storage capacity (SWC) explained over 80% of runoff variations (This model yielded the lowest AICc—15% lower than the single climate model—and the highest explanatory power, with R2 = 0.85 at 1-month, and 0.70 at 3-month scales). This study suggests that Mode2, with its precise characterization of seasonal differentiation and human dynamics, is more suitable for refined water resource management and extreme drought-flood prediction, whereas Mode1 remains efficient for analyzing interdecadal circulation effects. By addressing three key challenges—capturing monthly runoff nonstationarity, integrating multi-factor drivers, and validating runoff simulations—this study greatly improves runoff modeling and drought detection accuracy, laying a scientific foundation for adaptive management under the combined pressures of climate change and human activities.
量化气候变化和人类活动对非平稳径流动态的驱动效应是必要的。然而,对流域尺度上的非平稳特征及其多重驱动机制的系统评价仍然不足。本文通过对连续序列模型(model1)和月分割模型(model2)两种广义加性模型(GAMLSS)建模方法的比较,分析了黄河流域水文非平稳性特征,并结合时间、环流、气候和人为因素等协变量阐明了径流过程的驱动机制。结果表明:(1)以时间为协变量,模型2通过隔离季节动态显著增强了模型的稳健性。模型2将位置参数(μ)与月径流序列的平均相关性提高到R = 0.82(区间0.70 ~ 0.90),比模型1提高了30 ~ 50%。此外,非平稳标准化径流指数(NSRI)与实际水文波动更为吻合。(2)以环流指数为协变量,环流指数(AMO、PDO和NINO3)主导大尺度水文趋势,其中在模式2下,PDO对下游地区极端事件的调节作用更为明显。(3)气候-人类复合驱动模式对径流的拟合效果最好,特别是在较低的时间尺度(1、3、6个月尺度)中下游地区,总降水量、融雪量和土壤蓄水能力的相互作用解释了80%以上的径流变化(该模式的aicc最低,比单一气候模式低15%,解释能力最高,1个月和3个月的R2分别为0.85和0.70)。研究表明,模型2更适合于精细水资源管理和极端旱涝预测,而模型1更适合于分析年代际环流效应。通过解决月度径流非平稳性捕获、多因素驱动整合和径流模拟验证三个关键挑战,本研究极大地提高了径流建模和干旱探测的精度,为气候变化和人类活动联合压力下的适应性管理奠定了科学基础。
{"title":"Comparative analysis of GAMLSS modeling approaches for nonstationary runoff dynamics in the Yellow River Basin of China","authors":"Ben Niu ,&nbsp;Yi Li ,&nbsp;Yurui Fan ,&nbsp;Lei Gong ,&nbsp;Lei Wang ,&nbsp;Taishan Wang","doi":"10.1016/j.jhydrol.2026.135048","DOIUrl":"10.1016/j.jhydrol.2026.135048","url":null,"abstract":"<div><div>Quantifying the driving effects of climate change and human activities on nonstationary runoff dynamics is essential. However, the systematic assessments of nonstationary characteristics and their multiple driving mechanisms at the basin scale remain insufficient. This study compared two Generalized Additive Model for Location, Scale, and Shape (GAMLSS) modeling approaches–Continuous-series modeling (Mode1) and monthly-segmented modeling (Mode2)–to analyze the hydrological nonstationarity characteristics of the Yellow River Basin <em>in China</em> and elucidate the driving mechanisms of runoff processes by incorporating covariates of time, circulation, climate, and human factors. The results indicated that: (1) Taking time as a covariate, Mode2 significantly enhanced model robustness by isolating seasonal dynamics. Mode2 raised the average correlation of the location parameter (μ) with the monthly runoff series to R = 0.82 (range 0.70–0.90), a 30–50% increase over Mode1. Furthermore, the nonstationary standardized runoff index (NSRI) aligned more accurately with actual hydrological fluctuations. (2) Taking circulation indices as covariates, circulation indices (AMO, PDO and NINO3) predominantly governed large-scale hydrological trends, with PDO exerting a more pronounced regulatory effect on extreme events in the downstream region under Mode2. (3) The climate-human composite-driven model had the best fitting effect on runoff, particularly at lower timescales (1-, 3-, and 6-month scales) in the middle and lower reaches, where the interactions among total precipitation (TP), snowmelt (SMT), and soil water storage capacity (SWC) explained over 80% of runoff variations (This model yielded the lowest AICc—15% lower than the single climate model—and the highest explanatory power, with R<sup>2</sup> = 0.85 at 1-month, and 0.70 at 3-month scales). This study suggests that Mode2, with its precise characterization of seasonal differentiation and human dynamics, is more suitable for refined water resource management and extreme drought-flood prediction, whereas Mode1 remains efficient for analyzing interdecadal circulation effects. By addressing three key challenges—capturing monthly runoff nonstationarity, integrating multi-factor drivers, and validating runoff simulations—this study greatly improves runoff modeling and drought detection accuracy, laying a scientific foundation for adaptive management under the combined pressures of climate change and human activities.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"669 ","pages":"Article 135048"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Climate modulation and intensity-stratified moisture sources in major global river basins 全球主要河流流域的气候调节与强度分层水汽来源
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.jhydrol.2026.135049
Xingxing Zhang , Zhaocai Wang , Tomasz Janus , Hou Jiang , Zhaofei Liu , Liguang Jiang , Yizhu Zhu , Yaozhi Jiang , Zhijun Yao , Hua Wu
Understanding how atmospheric moisture pathways regulate precipitation variability is essential for basin-scale water security under climate change. Here we present a global, intensity-stratified analysis of moisture sources and transport across seven major river basins using ERA5 reanalysis and the WAM-2layers model. By combining precipitationshed diagnostics with empirical orthogonal function analysis, we identify dominant and higher-order moisture transport modes and assess their roles in seasonal and extreme precipitation. River basins are classified into ocean-dominated, mixed-source, and land-dominated regimes based on the structure and variability of moisture transport. Ocean-dominated basins exhibit coherent moisture pathways and strong coupling between precipitation and the leading transport mode, whereas land-dominated and high-latitude basins show weaker coupling and a greater reliance on higher-order modes, particularly during seasonal transitions and heavy precipitation events. Mixed-source basins maintain robust precipitation–transport relationships despite pronounced seasonal shifts. We further identify regime-dependent multi-decadal shifts in moisture source regions and seasonally varying climate influences on transport modes, demonstrating that mean moisture source fractions alone cannot explain precipitation variability and extremes. These findings improve our understanding of basin-specific hydroclimatic responses and offer valuable insights for future hydrological predictions and climate adaptation.
了解大气水分途径如何调节降水变率对于气候变化下流域尺度的水安全至关重要。本文利用ERA5再分析和WAM-2layers模式对7个主要流域的水汽来源和输送进行了全球强度分层分析。通过降水诊断与经验正交函数分析相结合,我们确定了主要和高阶水分输送模式,并评估了它们在季节性和极端降水中的作用。根据水分输送的结构和变化,将流域划分为海洋主导型、混合源主导型和陆地主导型。以海洋为主导的盆地表现出连贯的水汽通道和降水与主要运输模式之间的强耦合,而以陆地为主导的盆地和高纬度盆地表现出较弱的耦合和对高阶模式的更多依赖,特别是在季节过渡和强降水事件期间。尽管季节变化明显,但混合源盆地仍保持强劲的降水-输送关系。我们进一步确定了水汽源区的多年代际变化和季节变化的气候对运输模式的影响,表明平均水汽源区分数不能单独解释降水变率和极端事件。这些发现提高了我们对流域特定水文气候响应的理解,并为未来的水文预测和气候适应提供了有价值的见解。
{"title":"Climate modulation and intensity-stratified moisture sources in major global river basins","authors":"Xingxing Zhang ,&nbsp;Zhaocai Wang ,&nbsp;Tomasz Janus ,&nbsp;Hou Jiang ,&nbsp;Zhaofei Liu ,&nbsp;Liguang Jiang ,&nbsp;Yizhu Zhu ,&nbsp;Yaozhi Jiang ,&nbsp;Zhijun Yao ,&nbsp;Hua Wu","doi":"10.1016/j.jhydrol.2026.135049","DOIUrl":"10.1016/j.jhydrol.2026.135049","url":null,"abstract":"<div><div>Understanding how atmospheric moisture pathways regulate precipitation variability is essential for basin-scale water security under climate change. Here we present a global, intensity-stratified analysis of moisture sources and transport across seven major river basins using ERA5 reanalysis and the WAM-2layers model. By combining precipitationshed diagnostics with empirical orthogonal function analysis, we identify dominant and higher-order moisture transport modes and assess their roles in seasonal and extreme precipitation. River basins are classified into ocean-dominated, mixed-source, and land-dominated regimes based on the structure and variability of moisture transport. Ocean-dominated basins exhibit coherent moisture pathways and strong coupling between precipitation and the leading transport mode, whereas land-dominated and high-latitude basins show weaker coupling and a greater reliance on higher-order modes, particularly during seasonal transitions and heavy precipitation events. Mixed-source basins maintain robust precipitation–transport relationships despite pronounced seasonal shifts. We further identify regime-dependent multi-decadal shifts in moisture source regions and seasonally varying climate influences on transport modes, demonstrating that mean moisture source fractions alone cannot explain precipitation variability and extremes. These findings improve our understanding of basin-specific hydroclimatic responses and offer valuable insights for future hydrological predictions and climate adaptation.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 135049"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Hydrological connectivity and landscape composition shape nutrient export: Evidence from SWAT and machine learning analysis in the Longxi River Basin 水文连通性与景观组成形态养分输出:基于SWAT和机器学习分析的龙溪流域证据
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.jhydrol.2026.135013
Shaojun Tan , Jianfeng Xu , Kai Wang , Haiming Lu , Xianqiang Tang , Danyang Wang , Lishan Ran , Deti Xie , Jiupai Ni , Fangxin Chen , Wendi Wang , Eugenio Straffelini
Understanding how hydrological connectivity and landscape patterns influence nutrient export is critical for clarifying the mechanisms driving non-point source pollution in river basins, especially where agriculture is largely practice. This study employed the Soil and Water Assessment Tool (SWAT) to simulate total nitrogen (TN) and total phosphorus (TP) export loads in the Longxi River Basin (LRB, in China) during 2021–2022. Using Random Forest (RF) and partial least squares structural equation modeling (PLS-SEM), the research explored the influences of terrain, landscape configuration, landscape composition, and aggregated hydrological connectivity (AIC) on TN and TP exports. Results indicated that average summer TN and TP exports accounted for 51.11% and 52.55% of the annual totals, respectively. Liangping and Dianjiang Countiy, along with the adjacent Changshou Lake reservoir, exhibited the highest hydrological connectivity indices within the watershed, especially during summer. RF model analysis identified landscape composition and hydrological connectivity as the primary factors governing TN and TP exports. Findings highlight the importance of managing hydrological connectivity and optimizing landscape composition as strategies for reducing nutrient losses and mitigating non-point source pollution in watershed management.
了解水文连通性和景观格局如何影响养分输出,对于阐明驱动河流流域非点源污染的机制至关重要,尤其是在农业为主的地区。利用SWAT模拟了陇西流域2021-2022年的总氮(TN)和总磷(TP)输出负荷。利用随机森林(RF)和偏最小二乘结构方程模型(PLS-SEM),研究了地形、景观配置、景观组成和聚集水文连通性(AIC)对总氮和总磷输出的影响。结果表明,夏季平均总氮和总磷出口量分别占全年总氮和总磷出口量的51.11%和52.55%。梁平县和垫江县及其相邻的长寿湖水库在流域内水文连通性指数最高,尤其是在夏季。RF模型分析发现,景观组成和水文连通性是控制全氮和总磷出口的主要因素。研究结果强调了在流域管理中,管理水文连通性和优化景观组成作为减少养分损失和减轻非点源污染的战略的重要性。
{"title":"Hydrological connectivity and landscape composition shape nutrient export: Evidence from SWAT and machine learning analysis in the Longxi River Basin","authors":"Shaojun Tan ,&nbsp;Jianfeng Xu ,&nbsp;Kai Wang ,&nbsp;Haiming Lu ,&nbsp;Xianqiang Tang ,&nbsp;Danyang Wang ,&nbsp;Lishan Ran ,&nbsp;Deti Xie ,&nbsp;Jiupai Ni ,&nbsp;Fangxin Chen ,&nbsp;Wendi Wang ,&nbsp;Eugenio Straffelini","doi":"10.1016/j.jhydrol.2026.135013","DOIUrl":"10.1016/j.jhydrol.2026.135013","url":null,"abstract":"<div><div>Understanding how hydrological connectivity and landscape patterns influence nutrient export is critical for clarifying the mechanisms driving non-point source pollution in river basins, especially where agriculture is largely practice. This study employed the Soil and Water Assessment Tool (SWAT) to simulate total nitrogen (TN) and total phosphorus (TP) export loads in the Longxi River Basin (LRB, in China) during 2021–2022. Using Random Forest (RF) and partial least squares structural equation modeling (PLS-SEM), the research explored the influences of terrain, landscape configuration, landscape composition, and aggregated hydrological connectivity (AIC) on TN and TP exports. Results indicated that average summer TN and TP exports accounted for 51.11% and 52.55% of the annual totals, respectively. Liangping and Dianjiang Countiy, along with the adjacent Changshou Lake reservoir, exhibited the highest hydrological connectivity indices within the watershed, especially during summer. RF model analysis identified landscape composition and hydrological connectivity as the primary factors governing TN and TP exports. Findings highlight the importance of managing hydrological connectivity and optimizing landscape composition as strategies for reducing nutrient losses and mitigating non-point source pollution in watershed management.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"668 ","pages":"Article 135013"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Global quantification of the bidirectional dependence between vegetation productivity and multi-layer soil moisture 植被生产力与多层土壤水分双向依赖关系的全球量化
IF 6.3 1区 地球科学 Q1 ENGINEERING, CIVIL Pub Date : 2026-04-01 Epub Date: 2026-01-30 DOI: 10.1016/j.jhydrol.2026.135065
Ying Liu, Jiumeilin Shi, Hui Yue, Xu Wang
Soil moisture serves as a crucial water source for vegetation growth, while vegetation dynamics in turn regulate soil moisture through processes such as evapotranspiration and canopy interception. Quantitatively characterizing this mutual feedback is essential for optimizing hydrological processes and promoting coordinated vegetation–water management. However, the bidirectional interactions between soil moisture and vegetation productivity across different climate zones, vegetation types, and soil depths remain poorly understood. Based on Global Solar Induced Chlorophyll Fluorescence, soil moisture, the average air temperature at 2 m, and solar radiation datasets, this study employed trend analysis, causal inference, and multiple linear regression to explore the Granger causality between vegetation productivity and multi-layer soil moisture under different environmental conditions. Results revealed widespread bidirectional dependence between vegetation productivity and soil moisture across all soil layers, with interaction strength declining from 79.84% in the surface layer (0–10 cm) to 72.04% in the deep layer (100–200 cm). The magnitude of this bidirectional coupling varied significantly across climate zones: dependence peaked in surface soils within temperate regions (82.52%), while tropical zones exhibited maxima in the shallow (82.99%) and deep (78.05%) layers. Boreal zones showed the strongest dependence in the middle soil layer (76.25%). Furthermore, driven by differences in transpiration rates and water retention capacity, woody plants demonstrated higher average bidirectional dependence (79.4%) than herbaceous plants (75.75%), whereas shrubland vegetation exhibited relatively lower dependence (74%). Considering the spatial distribution of climate and vegetation types, tropical zones (dominated by evergreen broadleaf forests) and boreal zones (dominated by shrublands) both showed peak bidirectional dependence in the shallow soil layer. Other climate zones, primarily influenced by grassland vegetation, exhibited peak dependence within the surface soil layer. This study reveals the variability in bidirectional dependence between vegetation productivity and multilayer soil moisture across different climatic zones and vegetation types, which will provide a robust theoretical foundation for improving regional soil moisture regulation and guiding ecosystem restoration under changing climatic conditions.
土壤水分是植被生长的重要水源,而植被动态又通过蒸散发和冠层截流等过程调节土壤水分。定量表征这种相互反馈对于优化水文过程和促进协调的植被-水管理至关重要。然而,在不同气候带、植被类型和土壤深度中,土壤水分与植被生产力之间的双向相互作用仍然知之甚少。基于全球太阳诱导叶绿素荧光、土壤湿度、2 m平均气温和太阳辐射数据,采用趋势分析、因果推理和多元线性回归等方法,探讨不同环境条件下植被生产力与多层土壤湿度之间的格兰杰因果关系。结果表明,各土层植被生产力与土壤水分存在广泛的双向依赖关系,交互作用强度从表层(0 ~ 10 cm)的79.84%下降到深层(100 ~ 200 cm)的72.04%。这种双向耦合的程度在不同气候带之间存在显著差异:温带地区表层土壤的依赖性最大(82.52%),而热带地区表层土壤的依赖性最大(82.99%),深层土壤的依赖性最大(78.05%)。寒带对中层土壤的依赖性最强(76.25%)。此外,在蒸腾速率和保水能力差异的驱动下,木本植物的平均双向依赖(79.4%)高于草本植物(75.75%),而灌木植被的平均双向依赖(74%)相对较低。从气候和植被类型的空间分布来看,热带地区(常绿阔叶林为主)和寒带地区(灌丛为主)在浅层土壤中均表现出最大的双向依赖性。其他气候带主要受草地植被影响,在表层土壤中表现出峰值依赖性。该研究揭示了不同气候带和植被类型下植被生产力与多层土壤水分双向依赖关系的变异,为气候变化条件下改善区域土壤水分调节和指导生态系统恢复提供了坚实的理论基础。
{"title":"Global quantification of the bidirectional dependence between vegetation productivity and multi-layer soil moisture","authors":"Ying Liu,&nbsp;Jiumeilin Shi,&nbsp;Hui Yue,&nbsp;Xu Wang","doi":"10.1016/j.jhydrol.2026.135065","DOIUrl":"10.1016/j.jhydrol.2026.135065","url":null,"abstract":"<div><div>Soil moisture serves as a crucial water source for vegetation growth, while vegetation dynamics in turn regulate soil moisture through processes such as evapotranspiration and canopy interception. Quantitatively characterizing this mutual feedback is essential for optimizing hydrological processes and promoting coordinated vegetation–water management. However, the bidirectional interactions between soil moisture and vegetation productivity across different climate zones, vegetation types, and soil depths remain poorly understood. Based on Global Solar Induced Chlorophyll Fluorescence, soil moisture, the average air temperature at 2 m, and solar radiation datasets, this study employed trend analysis, causal inference, and multiple linear regression to explore the Granger causality between vegetation productivity and multi-layer soil moisture under different environmental conditions. Results revealed widespread bidirectional dependence between vegetation productivity and soil moisture across all soil layers, with interaction strength declining from 79.84% in the surface layer (0–10 cm) to 72.04% in the deep layer (100–200 cm). The magnitude of this bidirectional coupling varied significantly across climate zones: dependence peaked in surface soils within temperate regions (82.52%), while tropical zones exhibited maxima in the shallow (82.99%) and deep (78.05%) layers. Boreal zones showed the strongest dependence in the middle soil layer (76.25%). Furthermore, driven by differences in transpiration rates and water retention capacity, woody plants demonstrated higher average bidirectional dependence (79.4%) than herbaceous plants (75.75%), whereas shrubland vegetation exhibited relatively lower dependence (74%). Considering the spatial distribution of climate and vegetation types, tropical zones (dominated by evergreen broadleaf forests) and boreal zones (dominated by shrublands) both showed peak bidirectional dependence in the shallow soil layer. Other climate zones, primarily influenced by grassland vegetation, exhibited peak dependence within the surface soil layer. This study reveals the variability in bidirectional dependence between vegetation productivity and multilayer soil moisture across different climatic zones and vegetation types, which will provide a robust theoretical foundation for improving regional soil moisture regulation and guiding ecosystem restoration under changing climatic conditions.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"669 ","pages":"Article 135065"},"PeriodicalIF":6.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
期刊
Journal of Hydrology
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1