Journal of Hydrology-Regional Studies最新文献

{"title":"Retrieval of water quality parameters based on IOA-ML models and their response to short-term hydrometeorological factors","authors":"Wentong Hu,&nbsp;Donghao Miao,&nbsp;Chi Zhang,&nbsp;Zixian He,&nbsp;Wenquan Gu,&nbsp;Dongguo Shao","doi":"10.1016/j.ejrh.2024.102118","DOIUrl":"10.1016/j.ejrh.2024.102118","url":null,"abstract":"<div><h3>Study region</h3><div>The Honghu Lake (HHL) and Changhu Lake (CHL) in middle China.</div></div><div><h3>Study focus</h3><div>Large-scale and high-precision estimation of water quality parameters (WQPs) is critical in explaining the spatiotemporal dynamics and clarifying their response to short-term hydrometeorological factors. Six machine learning models optimized by intelligent optimization algorithms (IOA-ML) were developed to retrieve WQPs using paired <em>in situ</em> measurements and near-synchronous Sentinel-2 reflectance (R_rs). Furthermore, the response of pixel-based WQPs to short-term hydrometeorological factors were explored by generalized additive model (GAM).</div></div><div><h3>New hydrological insights for the region</h3><div>The results showed that R_rs curves were significantly correlated with WQPs concentration, which provided a solid foundation for WQPs retrieval. The best IOA-ML model for total phosphorus (TP), total nitrogen (TN), and permanganate index (COD_Mn) was extreme gradient boosting optimized by genetic algorithm (GA-XGB), while that for dissolved oxygen (DO) and turbidity was categorical boosting regression optimized by GA (GA-CBR). Coefficient of determination (R²) of the best retrieval models for the test sets of TP, TN, turbidity, COD_Mn and DO were 0.545, 0.418, 0.794, 0.798, and 0.653, respectively. The best retrieval models were applied to two big inland lakes and revealed that TP, TN, COD_Mn, and turbidity in HHL increased rapidly from 2016 to 2022, especially during 2021–2022. 81.4 %-91.5 % of the WQPs variations in HHL and 63.4 %-92 % in CHL can be explained by hydrometeorological factors.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102118"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 improved statistical bias correction method for Global Climate Model (GCM) precipitation projection: A case study on the CMCC-CM2-SR5 model projection in China’s Huaihe River Basin","authors":"Yuning Luo ,&nbsp;Ke Zhang ,&nbsp;Wen Wang ,&nbsp;Xinyu Chen ,&nbsp;Jin Feng ,&nbsp;Haijun Wang ,&nbsp;Wei Liu ,&nbsp;Cheng Guo ,&nbsp;Cuiying Chen ,&nbsp;Xiaozhong Wang","doi":"10.1016/j.ejrh.2024.102146","DOIUrl":"10.1016/j.ejrh.2024.102146","url":null,"abstract":"<div><div>Study region: We selected the China’s Huaihe River Basin as the study region.</div><div>Study focus: Bias correction is crucial for improving the accuracy of Global Climate Model (GCM) predictions. We proposed an improved statistical bias correction method called the EquiDistant Cumulative Distribution Function (CDF) matching method with least square fitting of CDF’s deviation (LS-EDCDF) to correct biases in GCM precipitation. The LS-EDCDF method incorporates recurrence periods and least squares with the determination of transfer functions relating observation to model simulation. We applied this and three other methods—EquiDistant Cumulative Distribution Function matching method (EDCDF), combined Linear Scaling and Cumulative Distribution Function matching method (LS-CDF) and Quantile-quantile mapping method (QUANT)—to correct biases in the CMCC-CM2-SR5 model. Performance was evaluated in four aspects. Taylor diagram statistical metrics and correlation coefficients are used to measure agreements between the basin-average observations and bias-corrected model precipitation and their CDFs during the validation period (2015–2020), respectively. The Expert Team on Climate Change Detection and Indices (ETCCDI) extreme precipitation indices and spatial patterns of extreme precipitation in July 2020 in the observations and bias-corrected data were then compared to evaluate the effectiveness of these methods on capturing precipitation extremes.</div><div>New hydrological insights for the region: Results show that the LS-EDCDF method outperforms the other three methods in correcting monthly CDFs, reducing biases, and preserving extreme precipitation. All results of these methods indicate that the CMCC-CM2-SR5 model tends to overestimate precipitation but performs well during the main flood seasons, especially for extreme precipitation. Future projections suggest decreasing interannual variability of precipitation, with a lower change rate during the flood season and a higher rate during the non-flood season. The bias-corrected data from this method can serve as a valuable input for projecting future floods in this important area of China.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102146"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Advancing hydrological modeling through multivariate calibration of multi-layer soil moisture dynamics","authors":"Yan He ,&nbsp;Huihui Mao ,&nbsp;Chen Wang ,&nbsp;Jinghao Hu ,&nbsp;Sarawut Ninsawat ,&nbsp;Xianfeng Song ,&nbsp;Guifei Jing ,&nbsp;Runkui Li ,&nbsp;Mingyu Wang ,&nbsp;Zheng Duan","doi":"10.1016/j.ejrh.2024.102125","DOIUrl":"10.1016/j.ejrh.2024.102125","url":null,"abstract":"<div><h3>Study region</h3><div>The Meichuan Basin, China</div></div><div><h3>Study focus</h3><div>Soil water processes are critical in hydrological modeling, yet most studies focus on surface moisture due to data limitations, which hampers accurate simulations of root zone soil moisture dynamics. To address this gap, we developed three calibration schemes: M1 and M2, two benchmarks that rely solely on traditional streamflow data and incorporate both streamflow data and top-layer soil moisture data, respectively. In contrast, M3 integrates both streamflow data and multi-layer soil moisture information from SMCI 1.0. These schemes aim to assess the added value of integrating multi-layer soil moisture data to enhance hydrological modeling performance.</div></div><div><h3>New hydrological insights for the region</h3><div>The M3 scheme yielded the most accurate simulation of the spatial and temporal distribution of multi-layer soil moisture compared to M1 and M2 benchmarks. In this subtropical humid basin, the M3 model effectively captured the pronounced fluctuations in soil moisture driven by frequent and intense precipitation events, as well as the seasonal variability between wet and dry periods. M3 also improved the accuracy of evapotranspiration simulations across all subbasins, while maintaining acceptable streamflow simulations at gauge stations. These findings underscore the importance of using advanced multi-layer soil moisture data in models to regulate hydrological processes and control water distribution within the hydrological cycle.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102125"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Estimation of inelastic skeletal storativity based on SAR-derived land subsidence and groundwater variation in Beijing Plain, China","authors":"Chenxia Li ,&nbsp;Yanbing Wang ,&nbsp;Jie Yu ,&nbsp;Huili Gong ,&nbsp;Xiaojuan Li ,&nbsp;Xiyue Yang ,&nbsp;Haowen Cheng ,&nbsp;Xiaohuan Li ,&nbsp;Kemiao Shao","doi":"10.1016/j.ejrh.2024.102161","DOIUrl":"10.1016/j.ejrh.2024.102161","url":null,"abstract":"<div><h3>Study region</h3><div>Beijing plain in the eastern of Beijing, China.</div></div><div><h3>Study focus</h3><div>Over the past three decades, more than 2 billion m³ of groundwater have been pumped annually in the Beijing Plain, resulting in approximately 431 km² of land subsidence of more than 50 mm annually. While most studies have identified a correlation between land subsidence and groundwater overexploitation, quantifying their relationship has been challenging. In this paper, the land subsidence data were obtained based on the persistent scatterer interferometric synthetic aperture radar (PS-InSAR, PSI) and the least square (LS) method. The parameter of inelastic skeletal storativity (<em>S</em>_<em>i</em>) of the confined aquifer was used as a quantitative indicator to describe the relationship between land subsidence and groundwater exploitation in the Beijing Plain.</div></div><div><h3>New hydrology insights</h3><div>Moreover, the paper found a robust correlation between groundwater overexploitation and land subsidence in the deep confined aquifer through groundwater monitoring data. From 2005–2016, <em>S</em>_<em>i</em> showed a gradual and continuous increase in a specific range. The abnormal change in <em>S</em>_<em>i</em> value during 2014–2015 may be associated with the recharge of shallow confined and unconfined aquifers in the Beijing Plain by the South-to-North Water Diversion Project. The <em>S</em>_<em>i</em> estimated in the study area can be utilized to accurately deduce the regional water level shifts, thereby aiding in the efficient and sustainable management of groundwater resources.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102161"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Estimation of water storage changes in a tropical lake-floodplain system through remote sensing","authors":"Thijs de Klein ,&nbsp;Victor Bense ,&nbsp;Syed Mustafa","doi":"10.1016/j.ejrh.2024.102173","DOIUrl":"10.1016/j.ejrh.2024.102173","url":null,"abstract":"<div><h3>Study region</h3><div>Lake Urema and its floodplain in Gorongosa National Park, Mozambique</div></div><div><h3>Study focus</h3><div>Tropical lowland lake-floodplain systems are increasingly threatened by climate change effects and other human-induced pressures. Determining the effect of these pressures on the water balance is challenging because of a lack of hydrological monitoring data, which impedes water management decisions. A collection of optical remote sensing and Synthetic Aperture Radar (SAR) scenes is used in combination with supervised classification algorithms and topographical data to derive lake volumes for the period 1984–2023, which are analyzed for trends and correlation with satellite-derived climate data.</div></div><div><h3>New hydrological insights for the region</h3><div>Although lake volumes show strong interannual variability, no significant historical trend is identified. A precipitation response time of approximately two months is observed, suggesting a considerable contribution of groundwater to the lake’s water balance. Minimum lake volumes found for the period 2014–2017 coincide with a prolonged period of below-average precipitation, indicating the effect of decreased groundwater recharge. Dry season lake volumes show weak correlation with cumulative precipitation in comparison to rainy season lake volumes, further indicating the importance of groundwater inflow for the dry season water balance. Results suggest that climate change effects and anthropogenic activities may have little short-term impact on the lake’s dry season volume, while altering groundwater recharge may have more significant long-term effects.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102173"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143152561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Geochemical-based appraisal of karst groundwater quality, west Nile Valley, central Egypt, for drinking and irrigation","authors":"Hassan Alzahrani ,&nbsp;Abdullah Basaloom ,&nbsp;Sayed Mosaad","doi":"10.1016/j.ejrh.2024.102152","DOIUrl":"10.1016/j.ejrh.2024.102152","url":null,"abstract":"<div><div><em>Study region:</em> west El-Minya region is located West Nile Valley in the central part of Egypt.</div><div><em>Study focus</em>: The research aims to evaluate the geochemical processes affecting the groundwater and its suitability for drinking and agricultural purposes. This was achieved through integrated the analysis of ionic concentration data, using Piper and Gibbs diagrams, ionic ratios, multivariate analysis, and Water Quality Indices (WQI).</div><div>New hydrological insight: Funding indicated that the groundwater varies from fresh to brackish. The water types are characterized by Na-Cl-SO₄ and Ca-Mg-SO₄-Cl. Binary diagrams and factor analysis identified key mechanisms regulating major ion chemistry, including silicate weathering and ion exchange, with a minor contribution from carbonate and gypsum dissolution. The Drinking Water Quality index (DWQI) indicated that 75 % of groundwater samples are appropriate for drinking, especially in the southern and middle of the study area. Various agricultural indices were used to assess groundwater suitability for irrigation, indicating that most samples are suitable for irrigation use. The Irrigation Water Quality Index (IWQI) indicated that 42.86 % of the groundwater samples fell in a moderate restriction, while the rest of the sample was divided between the high and low restriction classes. The study shows vulnerability in water quality, highlighting the need for improved groundwater management. Adjusting watering frequency and using modern irrigation methods, like drip and sprinkler systems, can enhance water-use efficiency and reduce aquifer depletion.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102152"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Spatial assessment of land use and land cover change impacts on groundwater recharge and groundwater level: A case study of the Hat Yai basin","authors":"Nantiya Indhanu ,&nbsp;Tanit Chalermyanont ,&nbsp;Tanan Chub-Uppakarn","doi":"10.1016/j.ejrh.2024.102097","DOIUrl":"10.1016/j.ejrh.2024.102097","url":null,"abstract":"<div><h3>Study region</h3><div>Hat Yai Basin, Thailand.</div></div><div><h3>Study focus</h3><div>This study aimed to assess the impacts of land use and land cover changes on groundwater recharge and groundwater levels—specifically, the effects of increasing built-up areas and urban expansion. The MOLUSCE (plug-in QGIS) software was used to analyze land use and land cover changes. The groundwater recharge estimation in this study was conducted using the WetSpass model, and the groundwater level was simulated using MODFLOW.</div></div><div><h3>New hydrological insights for the region</h3><div>The findings indicate that the Hat Yai basin has experienced its highest increase in built-up areas and found a decrease in the average recharge rate for 2017 compared to 2007. Correspondingly, a simulation of groundwater levels indicates that the overall groundwater level has decreased. Spatially, the Hat Yai district, which exhibited the highest increase in built-up areas, experienced a decrease in groundwater levels. In contrast, the Khuan Niang district, which had the largest increase in perennial areas, demonstrated increased groundwater levels. The findings show that increasing built-up areas decreases the recharge rate, consequently lowering groundwater levels. The spatial assessment is proved to be more effective in illustrating positive and negative impacts than the basin's overall average. Such spatial assessment is valuable for water resource management planning and addressing localized water resource issues that may differ across various areas.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102097"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Characteristics of compound heat and drought events during the spring maize growing season in Northeast China Based on a novel daily-scale analysis framework","authors":"Jianhua Yang ,&nbsp;Jianjun Wu ,&nbsp;Lei Zhou ,&nbsp;Hongkui Zhou ,&nbsp;Zhenqing Zhang ,&nbsp;Ruilin Zhang","doi":"10.1016/j.ejrh.2024.102140","DOIUrl":"10.1016/j.ejrh.2024.102140","url":null,"abstract":"<div><h3>Study Region</h3><div>The Northeast China (NEC) is located in the northeastern part of China (117.78°E-135.08°E, 38.71°N-53.55°N).</div></div><div><h3>Study focus</h3><div>To address the limitations in previous studies that could not monitor compound heat and drought events (CHDEs) at a daily-scale during crop growing seasons, we developed a daily-scale method for analyzing CHDEs.</div></div><div><h3>New hydrological insights for the region</h3><div>We found: (1) CHDE frequency, duration, and severity were higher in the south and west of NEC, especially in the vegetative growth stage (VGS) compared to the reproductive stage (RGS). (2) Compared to 1961–1990, during 1991–2020, most stations showed more severe CHDEs during the EGS, VGS and RGS of spring maize. (3) Throughout the entire period (1961–2020) and the earlier period (1961–1990), drought-dominated CHDEs were more frequent during the EGS and VGS of spring maize. In the later period (1991–2020), heat-dominated CHDEs became more prevalent. For RGS, drought-dominated CHDEs were more likely in both the entire period and the later period, while heat-dominated CHDEs were more common during the earlier period. This research advances understanding of CHDEs in spring maize and offers a novel daily-scale framework for crop CHDE analysis.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102140"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Assessment of multidecadal precipitation seasonality in the panama canal watershed","authors":"István Gábor Hatvani ,&nbsp;Nayara Azevedo de Castro Souza ,&nbsp;Russell S. Harmon ,&nbsp;Jorge A. Espinosa ,&nbsp;Zoltán Kern","doi":"10.1016/j.ejrh.2025.102213","DOIUrl":"10.1016/j.ejrh.2025.102213","url":null,"abstract":"<div><h3>Study Region</h3><div>The 3000 km² of the Panama Canal Watershed.</div></div><div><h3>Study Focus</h3><div>This study provides insight into the spatiotemporal behavior of precipitation across the PCW<span><span>¹</span></span> utilizing 6-day rainfall records from 29 meteorological stations from 1950 to 2019. The focus interval of 2000–2017 offered the most complete spatiotemporal coverage of the long-term seasonal variability explored by hierarchical cluster analysis. Since the ENSO<span><span>²</span></span> is a key driver of hydroclimate variability in central Panama, differences in the rainfall patterns during the six most prominent El Niño and La Niña events, having respective ENSO indices of &gt; 1.80 and &lt; ˗1.63, were compared to quasi-neutral conditions for the assigned hydroclimatological domains.</div></div><div><h3>New Hydrological Insights for the Region</h3><div>Three spatial domains of similar patterns of seasonal and geographical distribution of rainfall were delineated in PCW by clustering the precipitation-seasonality time series. Stations in the northeastern and northwestern domains of the PCW experience higher average daily precipitation, influenced by the interplay of the annual movement of the ITCZ<span><span>³</span></span> across Panama and weather systems over the Caribbean Sea. The southwestern group of stations reflect the drier conditions prevailing along Panama’s Pacific coast. The most significant ENSO effect is observed in the northeastern part of the PCW, which displays distinct rainfall patterns during the early and late stages of the annual wet season. Since an increase in consecutive La Niña events is expected, it may potentially lead to more precipitation, along with prolonged wet and shorter dry seasons.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"58 ","pages":"Article 102213"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143183590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Agricultural drought monitoring using modified TVDI and dynamic drought thresholds in the upper and middle Huai River Basin, China","authors":"Dui Huang ,&nbsp;Tao Ma ,&nbsp;Jiufu Liu ,&nbsp;Jianyun Zhang","doi":"10.1016/j.ejrh.2024.102069","DOIUrl":"10.1016/j.ejrh.2024.102069","url":null,"abstract":"<div><h3>Study Region</h3><div>The upper and middle reaches of the Huai River Basin.</div></div><div><h3>Study Focus</h3><div>The study seeks to enhance the monitoring of agricultural drought by introducing a modified temperature vegetation drought index (TVDIm) and developing a flexible drought threshold that considers crop growth stages and water requirements. This approach intends to accurately identify areas impacted by drought. The TVDIm enhances the detection of wet and dry boundaries in the regions of land surface temperature (LST)—normalized difference vegetation index (NDVI)—and LST—enhanced vegetation index (EVI). The TVDIm derived using the NDVI and EVI indices are denoted as TVDI_NDVIm and TVDI_EVIm, respectively.</div></div><div><h3>New Hydrological Insights</h3><div>The findings indicate that TVDIm, particularly TVDI_EVIm, has a stronger association with soil moisture at different depths in comparison to conventional TVDI. The annual comparisons demonstrate that the TVDIm index is associated with soil moisture throughout several soil layers, accommodating the diverse water needs of different phases of crop growth. Using the strong correlation between TVDI_EVIm and observed data, we developed dynamic drought thresholds (ranging from 0.8 to 0.85) that are tailored to different crop growth stages. These thresholds greatly reduce the spatial extent of areas classified as experiencing drought, decreasing by 15,500–79,700 square kilometres compared to the threshold of 0.67. Additionally, they increase the intra-annual variability of areas affected by drought.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"57 ","pages":"Article 102069"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}