Journal of Hydrology最新文献

{"title":"A2DWQPE: Adaptive and automated data-driven water quality parameter estimation","authors":"Yiyun Hu,&nbsp;Fangling Pu,&nbsp;Chuishun Kong,&nbsp;Rui Yang,&nbsp;Hongjia Chen,&nbsp;Xin Xu","doi":"10.1016/j.jhydrol.2023.130363","DOIUrl":"10.1016/j.jhydrol.2023.130363","url":null,"abstract":"<div><p><span><span><span>Accurate remote sensing estimation of </span>inland water quality parameters (WQPs) plays a crucial role in guiding </span>water resource management<span><span><span>. To achieve this, researchers have explored various data-driven approaches utilizing machine learning (ML) techniques. However, there are two major challenges in WQPs estimation for inland waters. Firstly, current data-driven approaches focus on building a unified estimation model for an entire study area, which underestimates the complex dynamics of water constituents and optical properties. Secondly, ML models, particularly </span>neural networks, require extensive hyperparameter tuning and are not user-friendly for researchers lacking relevant background and experience. In this paper, we propose an innovative method called adaptive and automated data-driven water quality parameter estimation (A2DWQPE) to address both challenges. Our method operates under the assumption that water bodies with similar spectral characteristics should share the same WQP estimation model. A2DWQPE is composed of three phases. Firstly, water types are automatedly classified by unsupervised hierarchical clustering according to spectral similarity. Then, optimal Deep Neural Network (DNN) models for estimating WQPs from multi-spectral satellite images are customized for each water type utilizing </span>Bayesian optimization<span><span> (BO). Finally, the target WQP is estimated based on the type-specific estimates and degree of membership of each water type. To evaluate the effectiveness of A2DWQPE, we applied it to estimate Secchi disk depth (SDD) in </span>Lake Erie<span> with in situ measurements<span> and Moderate Resolution Imaging Spectroradiometer (MODIS) images. The results demonstrate that A2DWQPE outperforms the traditional approaches of developing a unified model for the entire study area. A2DWQPE achieved high accuracy with coefficient of determination (</span></span></span></span></span><span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span><span><span>) over 0.72 and root mean square error (RMSE) below 1.4 m. Our method also outperforms the methods that applied Genetic Algorithm (GA) and Particle </span>Swarm<span> Optimization (PSO) instead of BO, and several traditional ML algorithms. We firmly believe that A2DWQPE holds great potential for accurate inland water quality estimation and will contribute significantly to various applications in water quality monitoring and pollution prevention.</span></span></p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130363"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50164629","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}

{"title":"Multifractal detrended fluctuation analysis of rainfall time series in the Guadeloupe archipelago","authors":"Javier Gómez-Gómez ,&nbsp;Thomas Plocoste ,&nbsp;Esdra Alexis ,&nbsp;Francisco José Jiménez-Hornero ,&nbsp;Eduardo Gutiérrez de Ravé ,&nbsp;Silvere Paul Nuiro","doi":"10.1016/j.jhydrol.2023.130377","DOIUrl":"10.1016/j.jhydrol.2023.130377","url":null,"abstract":"<div><p>Due to the vulnerability of the Caribbean islands to the climate change issue, it is important to investigate the behavior of rainfall. In addition, the soil of the French West Indies Islands has been contaminated by an organochlorine<span> insecticide (Chlordecone) whose decontamination<span><span> is mainly done by drainage water. Thus, it is crucial to investigate the fluctuations of rainfall in these complex environments. In this study, 19 daily rainfall series recorded in different stations of Guadeloupe archipelago from 2005 to 2014 were analyzed with the multifractal detrended fluctuation analysis (MF-DFA) method. The aim of this work is to characterize the long-range correlations and multifractal properties of the time series and to find geographical patterns over the three most important islands: Basse-Terre, Grande-Terre and Marie-Galante. This is the first study that addresses the analysis of multifractal properties of rainfall series in the Caribbean islands. This region is typically characterized by the almost constant influence of the </span>trade winds<span> and a high exposure to changes in the general atmospheric circulation. 12 stations exhibit two different power-law scaling regions in rainfall series, with distinct long-range correlations and multifractal properties for large and small scales. On the contrary, the rest of stations only show a single region of scales for relatively small scales. Hurst exponents reveal persistent long-range correlations which agree with other studies in nearby tropical locations. In the most eastern analyzed areas, larger scales exhibit higher persistence than smaller scales, which suggests a relationship between persistence and the highest exposure to the trade winds. Stronger conclusions can be drawn from multifractal spectra, which indicate that most rainfall series have a multifractal nature with higher complexity and degree of multifractality at the smallest scales. Furthermore, a clear dependence of multifractal nature on the latitude is revealed. All these results showed that MF-DFA is a robust tool to assess the nonlinear properties of environmental time series in a complex area.</span></span></span></p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130377"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50164631","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}

{"title":"High uncertainty of evapotranspiration products under extreme climatic conditions","authors":"Long Qian ,&nbsp;Zhitao Zhang ,&nbsp;Lifeng Wu ,&nbsp;Shaoshuai Fan ,&nbsp;Xingjiao Yu ,&nbsp;Xiaogang Liu ,&nbsp;Yalan Ba ,&nbsp;Haijiao Ma ,&nbsp;Yicheng Wang","doi":"10.1016/j.jhydrol.2023.130332","DOIUrl":"10.1016/j.jhydrol.2023.130332","url":null,"abstract":"<div><p>Terrestrial Evapotranspiration (ET) is an important process for understanding regional or global water, energy, and carbon cycles, and with the development of satellite observations and increased research investment, grid ET products covering a broad spatial extent are becoming more readily available. However, as global warming becomes a reality and extreme climate events occur worldwide, existing studies do not go far enough to verify that these grid products can still be used under extreme climate conditions. This study evaluates nine global ET products, including land surface reanalysis products (GLDAS_CLSM, GLDAS_NOAH, ERA5, and FLDAS), remote sensing (RS) products (GLEAM_v3.6b, MOD16A2, and PMLv2), and multi-source data fusion products (REA and Synthesized), using observations from 153 flux towers worldwide. The objective is to evaluate their performance in estimating ET under extreme climatic conditions (high temperature, high vapor pressure deficit (VPD), and drought). The results indicate that the estimation accuracy of all ET products is significantly reduced under extreme climatic conditions, showing high uncertainty, and this impact is most severe in the Americas (AM) region. Overall, multi-source data fusion products showed the best estimation performance and were less affected by extreme climatic conditions. Among the remote sensing modeling products, GLEAM_v3.6b showed the best performance, while MOD16A2 has the lowest estimation accuracy. Land surface reanalysis products were most affected by extreme conditions, with CLSM and NOAH showing similar performance and ERA5 having the largest errors (RMSE_ERA5 = 1.699 mm/d, MAE_ERA5 = 1.294 mm/d). The ET products show significant error fluctuations and overestimation (PBias &gt; 0.5) in most of North America, and there is a decline in simulation accuracy in arid and semi-arid regions near 30°N, with most ET products showing overestimation. The most significant errors were observed in cropland areas (CRO) and deciduous broadleaf forest areas (DBF), with significant overestimation in mixed forest areas (MF). The results of this study provide valuable insights for researchers in selecting ET products under extreme climatic conditions and encourage product developers to consider uncertainty under such conditions, thereby improving product accuracy.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130332"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50164833","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}

{"title":"Exploring an intelligent adaptation method of hydrological model parameters for flood simulations based on the light gradient-boosting machine","authors":"Kangling Lin ,&nbsp;Sheng Sheng ,&nbsp;Hua Chen ,&nbsp;Yanlai Zhou ,&nbsp;Yuxuan Luo ,&nbsp;Lihua Xiong ,&nbsp;Shenglian Guo ,&nbsp;Chong-Yu Xu","doi":"10.1016/j.jhydrol.2023.130340","DOIUrl":"10.1016/j.jhydrol.2023.130340","url":null,"abstract":"<div><p>Traditional hydrological modeling methods use a set of parameters to simulate flood processes with complex causes and variable intensity, which can easily lead to parameter instability. To address the problem of parameter instability, this study proposes an approach integrating the hydrological model with Intelligent Adaptation Parameters (IAP), whose intelligent adaptation relationship is established by the light gradient-boosting machine (LightGBM) based on individual calibration parameters by each flood event and flood characteristics including flood-caused rainstorm information and initial soil moisture. A widely used hydrological model, Xin 'anjiang (XAJ) model, is chosen to be integrated with IAP (XAJ-IAP) in this study, which has a relatively complex structure and a total of 15 model parameters. The obtained findings demonstrate that: (1) recalibrating the sensitive runoff concentration and separation parameters with a single flood leads to a notable enhancement in simulation accuracy, while simultaneously considering the model's physical significance; (2) the XAJ overestimates large floods and underestimates small floods. Compared with the XAJ, the XAJ-IAP has a better rain-flood response relationship and simulation accuracy for floods of different magnitudes, solving the problem of parameter instability that exists in XAJ; and (3) evaluated in terms of information gain, sensitive parameters contribute the most to the establishment of the intelligent adaptation relationship in the LightGBM compared to flood-caused rainstorm information and initial soil moisture, indicating that sensitive parameters are the most important input features of the LightGBM. It can be concluded that the intelligent adaptation system can not only solve the problem of parameter instability that exists when traditional hydrological models simulate complex and changeable floods, but also further reveal the relationship between the model and floods.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130340"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50164916","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}

{"title":"The influence of anthropogenic climate change on meteorological drought in the Lancang-Mekong River basin","authors":"Xingye Han ,&nbsp;Qiongfang Li ,&nbsp;Xiaoqiang Yang ,&nbsp;Shuhong Xu ,&nbsp;Zhenhua Zou ,&nbsp;Mingjiang Deng ,&nbsp;Wen Wang","doi":"10.1016/j.jhydrol.2023.130334","DOIUrl":"10.1016/j.jhydrol.2023.130334","url":null,"abstract":"<div><p>Frequent occurrence of droughts in the Lancang-Mekong River Basin (LMRB) has produced incalculable impacts on human livelihood and river ecosystem. However, the roles of natural and anthropogenic forcings in the spatio-temporal evolution and characteristics of droughts have yet to be comprehensively explored, nor being well disentangled. In this study, two reanalysis climate datasets and an ensemble of 9 CMIP6 model simulations were used to investigate the influences of natural and anthropogenic external forcings on drought evolutions in LMRB during 1951–2020, using the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI). The changes in drought frequency, duration, severity, intensity, and affected area and their Copula-based multi-dimensional drought probabilities were also analyzed at both gridded and sub-regional scales. Results reveal: (1) for SPI, a robust forcing from greenhouse gases is substantially detected in observational signals during dry season, especially in spring; (2) for SPEI, the anthropogenic signal is strongly attributable, especially over longer temporal scales and larger geographical areas, while the natural forcing is only detectable in dry season with underestimated degrees of changes; (3) for univariate drought characteristics, the human activities have exacerbated drought conditions throughout LMRB, especially the drought frequency in the lower Lancang River basin, and drought duration and severity in the middle and lower Mekong River basin; (4) for multi-dimensional drought characteristics, anthropogenic activities have general decreased the co-occurrence probability of multi-dimensional droughts in the Lancang Rivier basin, but increased the risk of multi-dimensional drought events associated with long duration in the Mekong River basin. These findings could be beneficial to better understand the impacts of anthropogenic climate change on droughts and provide a timely evidence base for drought mitigation in the important <em>trans</em>-boundary regions of LMRB under a changing environment.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130334"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50164949","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}

{"title":"Evaluation of ecological buffer zone based on landscape pattern for non-point source pollution control: A case study in Hanjiang River basin, China","authors":"Weifeng Xie ,&nbsp;Jiake Li ,&nbsp;Yiwen Liu ,&nbsp;Kai Peng ,&nbsp;Ke Zhang","doi":"10.1016/j.jhydrol.2023.130341","DOIUrl":"10.1016/j.jhydrol.2023.130341","url":null,"abstract":"<div><p>The deterioration of ecological environment caused by non-point source pollution (NPS) has seriously threatened human health and socioeconomic development. Effective identification of critical source areas and selecting appropriate best management practices (BMPs) for watersheds are the keys to controlling NPS. This paper, using Hanjiang River basin, the vital water source for the South-to-North Water Division, China, as a case study, presents a method for accurate critical source areas dentification according to the spatial distribution characteristics of underlying surface and pollution load by coupling NPS risk index (NPPRI), Minimum Cumulative Resistance (MCR) Model, and Soil and Water Assessment Tool (SWAT). In this research, ten single and three combined scenarios are set up in the critical source areas, including three non-engineering management practices, two engineering management practices, and five ecological buffer zones. Finally, the effect of BMPs for non-point source pollution is assessed by using landscape pattern theory and information entropy method. Furthermore, the influences of the five ecological buffer zones on the characteristics of landscape in watershed and the response relationship between the landscape pattern and NPS are analyzed. The following findings are obtained: (1) The critical source areas were mainly located in the south-central and southeastern part of the study area, accounting for 35.9 % of the total watershed area, and yielding 54.2 % and 60.7 % of the total nitrogen(TN) and total phosphorus(TP) loads in the watershed; (2) All ecological buffer zones play a positive role in NPS control with an average reduction rate of 32.1 % for TN and 46.7 % for TP, and the control effectiveness for TP are better than that for TN; (3) The deployment of the five ecological buffer zones have a significant impact on the interspersion juxtaposition index (IJI), the connectivity of the “sink” landscape is enhanced, the diversity of the “source” landscape is reduced and the “sink” landscape’s ability of interception is boosted; (4) The calculation result of information entropy shows the highest attribute value of practices in the ecological buffer zones is Buffer 200 m. Overall, the findings serve as a reference for NPS control and water environment management in the watershed and strengthen the feasibility of implementing of BMPs in the watershed.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130341"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50165033","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}

{"title":"Re-inventing Bethlahmy method for estimating probable maximum precipitation","authors":"Jaya Bhatt ,&nbsp;V.V. Srinivas","doi":"10.1016/j.jhydrol.2023.130344","DOIUrl":"10.1016/j.jhydrol.2023.130344","url":null,"abstract":"<div><p>The design and risk analysis of large-scale hydraulic structures (e.g., dams) and sensitive installations (e.g., nuclear facilities) downstream of those structures rely on design flood corresponding to probable maximum precipitation (PMP). In areas where there is a sparsity of information on hydrometeorological variables, practitioners use various statistical methods to arrive at a PMP estimate, assuming it to be the possible upper bound for precipitation. However, the assumption is violated in different parts of the world. Hence, there is a need to improve the existing statistical methods and develop their potential alternatives. Against this backdrop, this paper proposes a new variant of a non-parametric method (Bethlahmy) to facilitate the estimation of PMP at locations with sparse records of extreme precipitation. It involves mapping of datapoints in annual maximum series and their ranks to a non-dimensional space (NDS) and using the information on sample size and observed maximum precipitation in the NDS to arrive at a surrogate variable representing PMP, which is eventually mapped back to PMP in the original space. The effectiveness of the proposed Bethlahmy variant over various existing statistical techniques is illustrated through Monte Carlo Simulation experiments and a case study on 37,872 stations from a global precipitation database. The existing techniques include the original Bethlahmy and Hershfield methods, conventional probabilistic approach, and relevant variant(s). Insight is provided into the relative performance of these methods, as there is a dearth of such attempts in the literature. Results indicate that the proposed Bethlahmy variant exhibits better performance than other methods/variants across samples varying in size and extreme precipitation characteristics, making it a promising statistical alternative for PMP estimation.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130344"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50165035","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}

{"title":"Capturing cascading effects under urban flooding: A new framework in the lens of heterogeneity","authors":"Jiajing Li ,&nbsp;Gaofeng Liu ,&nbsp;Huimin Wang ,&nbsp;Jing Huang ,&nbsp;Lei Qiu","doi":"10.1016/j.jhydrol.2023.130249","DOIUrl":"10.1016/j.jhydrol.2023.130249","url":null,"abstract":"<div><p><span><span>Increasing urban flooding posed serious threat to urban safety and sustainable development. The heterogeneity of hazard-bearing bodies is one of the important reasons for the variability of cascading failure scenarios in floods. Most previous studies have focused on failure propagation risks among specific types of hazard-bearing bodies, making it impossible to conduct a systematic analysis of the damage caused by persistent flooding in cities. In contrast to conventional graph representations, the heterogeneous hazard-bearing bodies network (HHBBN) based on heterogeneous functional graph theory was constructed in this paper and used to capture the relevant associations of urban resources in a flood. The HHBBN takes into account heterogeneity such as sensitivity and service </span>diffusivity, and functionalities related to hazard-bearing bodies are represented as nodes, with service relationships and geographical associations depicted as edges. To further study the performance change of HHBBN in urban areas during </span>rainstorm flooding, the cascading failure of HHBBN under continuous disturbance was also simulated. The proposed network modeling and cascading failure simulation methods were tested in Futian District of Shenzhen City, China. The case results demonstrate that the heterogeneous hazard-bearing bodies are interdependent and networked, which causes flood damage to spread more quickly and widely. Furthermore, the larger degree and more propagating hazard-bearing bodies are the key factors affecting the cascading failure of heterogeneous hazard-bearing bodies.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130249"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50165532","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}

{"title":"Managed phreatic zone recharge for irrigation and wastewater treatment","authors":"Darrell W.S. Tang ,&nbsp;Sjoerd E.A.T.M. Van der Zee ,&nbsp;Dominique M. Narain-Ford ,&nbsp;Gé A.P.H. van den Eertwegh ,&nbsp;Ruud P. Bartholomeus","doi":"10.1016/j.jhydrol.2023.130208","DOIUrl":"10.1016/j.jhydrol.2023.130208","url":null,"abstract":"<div><p>Managed phreatic zone recharge with marginal water, using (existing) drainage systems, raises the water table and increases water availability for crops. This is a newly developed method of freshwater conservation and marginal water treatment and disposal, but risks crop and environmental contamination. The fate of contaminants of emerging concern (CECs) within the irrigated water is addressed. We introduce numerical and analytical models, inspired loosely by a field site where treated domestic wastewater is used for subsurface irrigation. The treated wastewater would otherwise have been discharged into rivers, thereby spreading downstream. Model results show that minimal amounts of CECs are transported to deeper aquifers. Crops are not contaminated, except during dry years where small amounts of mobile CECs rise to the root zone, but then only directly above each irrigation drain. Under an annual precipitation surplus, less-mobile solutes are thus unlikely to ever enter the root zone. The primary mechanism of solute transport is lateral advection within the phreatic aquifer. Despite spatio-temporal heterogeneity in water flux magnitudes and directions, contaminant retardation does not significantly alter mass balance outcomes, only how fast it gets there. Therefore, persistent CECs pose the greatest risks, though overall environmental and crop contamination risks appear low. To maximize complementarity with subsurface irrigation systems, future advances in water treatment technologies should focus on removing persistent CECs. However, the system may be unsuitable for climates with annual precipitation shortages, as CECs may accumulate in the root zone and crops.</p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130208"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0022169423011502/pdfft?md5=84adf1abc3dcab2bc36789bf9afc1a55&pid=1-s2.0-S0022169423011502-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50165546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Long-distance recovery of nonuniform suspended load in the Middle Yangtze River owing to upstream damming","authors":"Meirong Zhou,&nbsp;Junqiang Xia,&nbsp;Yifei Cheng,&nbsp;Yu Mao","doi":"10.1016/j.jhydrol.2023.130263","DOIUrl":"10.1016/j.jhydrol.2023.130263","url":null,"abstract":"<div><p><span><span>The amount of suspended sediment entering the Middle Yangtze River (MYR) was greatly reduced owing to the operation of the Three Gorges Dam (TGD) and other upstream dams, which has caused the process of </span>sediment transport in the MYR at a severe non-equilibrium state. A detailed investigation was conducted into the transport of nonuniform suspended load in the MYR using about 30-year observed data: (i) firstly, the spatiotemporal variations in fractional sediment fluxes were investigated during the pre- and post-TGD periods. The total sediment flux decreased after the TGD operation, and the magnitude for the coarse fraction (</span><em>d</em> &gt; 0.125 mm) was smaller than those for the fine (<em>d</em> &lt; 0.031 mm) and medium (<em>d</em><span> = 0.031–0.125 mm) fractions; moreover, the sediment flux for each fraction continuously recovered along the 955-km-long reach, with the recovery distance for the coarse fraction being much shorter than the other two fractions; it was mainly attributed to the fact that the riverbed could supply abundant coarse sediment to the flow, and this fraction experienced a considerably higher recovery degree than the other two fractions; (ii) secondly, the sediment budgets for the fine, medium and coarse fractions were calculated to assess the contributions of different sediment sources to the recovery of graded sediments in the MYR. About 50 %, 29 % and 14 % of the increased fractional sediment amounts for fine, medium and coarse fractions were originated from the tributary confluence, while the remaining sediment was supplied from the riverbed during the process of channel erosion. Therefore, the recovery of suspended load was largely attributed to the supply of sediment from the riverbed, especially for the coarse fraction; (iii) finally, the impacts of the altered flow-sediment regime and the bed-material composition on sediment recovery efficiency were analysed. The sediment recovery efficiency greatly increased after the TGD operation, which was caused by the reduced sediment concentration; and the sediment recovery efficiency for the coarse fraction was much larger than those for the fine and medium sediment fractions. It is attributed to the fact that the channel can provide abundant coarse sediment to the flows in the MYR, while the sediment recovery efficiencies of fine and medium fractions were restricted by the low degree of sediment supply from the riverbed.</span></p></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"626 ","pages":"Article 130263"},"PeriodicalIF":6.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50165548","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}