Hydrological Processes最新文献

{"title":"Saltwater Circulation Driven by Shoreline Curvature in Coastal Aquifers","authors":"Xuan Yu,&nbsp;Lanxuan He,&nbsp;Rongjiang Yao,&nbsp;Zexuan Xu,&nbsp;George Kourakos,&nbsp;Jie Yang,&nbsp;Franklin W. Schwartz","doi":"10.1002/hyp.70207","DOIUrl":"https://doi.org/10.1002/hyp.70207","url":null,"abstract":"<div>\u0000 \u0000 <p>In coastal lowland and plains, where dense populations and extensive agriculture thrive, fresh water is a necessity. Management of coastal groundwater requires quantitative models of groundwater flow and transport to reveal salinity distributions and submarine groundwater discharge (SGD). Historically, computational burdens in modelling coastal groundwater necessitated the use of 2-D models along cross-sections. However, a variety of different features add fully three-dimensional complexity to near-shore groundwater flow and complex patterns of saline-fresh groundwater mixing. Shoreline geometry is one such feature which has not been systematically assessed. We modelled mixing processes between freshwater and saltwater in three dimensions using the coupled surface/subsurface flow and transport code HydroGeoSphere. Various concave and convex coastlines were constructed with geomorphological features characteristic of those in China. Our simulation suggested that the lateral groundwater flow can cause significant velocity perpendicular to the plane of the cross-sections, accounting for from 2% to 12% of longitudinal velocity. The lateral velocity component of groundwater increases with shoreline curvature, causing nonlinear responses of lateral saltwater circulation. The mixing zone and SGD change as a function of coastline curvature, which depends mainly on the magnitudes of convergent/divergent flow. In addition, shoreline curvature increases the mean travel time of fresh SGD, while a limited impact on the travel time of saline SGD is found. Our results highlight the nonnegligible influence of coastline geometry on lateral groundwater flow, freshwater-saltwater mixing, and SGD characteristics in commonly concave and convex shorelines. This study has important implications for management of groundwater resources, comprehension of biogeochemical processes along the coastal lowlands and plains.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Mountain Soil Water Storage and Release in a Colombian Páramo With APSIS-InSAR Data","authors":"Andrew V. Bradley,&nbsp;David J. Large,&nbsp;Jeffrey Mauricio Prieto Naranjo,&nbsp;Wouter Buytaert,&nbsp;Emily Mitchell,&nbsp;Andrew Sowter,&nbsp;Mauricio Diazgranados,&nbsp;Boris Ochoa-Tocachi,&nbsp;Charles George,&nbsp;France F. Gerard","doi":"10.1002/hyp.70214","DOIUrl":"https://doi.org/10.1002/hyp.70214","url":null,"abstract":"<p>Direct observation of montane and upland water resources provides valuable data in support of national scale water management and policy, but direct observation is challenging on large spatial scales. To address the need for large spatial scale hydrological data we use InSAR surface motion signals, indicative of surface swelling due to increased soil water content, at approximately 90 m resolution over a tropical Colombian mountain range covered with Páramo, a biome widespread along the Northern Andes. Considering uncertainty of vegetation and mountainous terrain on the InSAR signal, we observe a regional, spatially consistent sequence of soil surface motion, which can be related to storage and movement of water through montane catchments. Swelling on the ridges and upper slopes occurs during the wet season and is consistent with infiltration and increased saturation of ridge and upper slope soils. This is followed by a marked swelling of the valley floors towards the end of the wet season and into the dry season. The InSAR signal also captures movement of water through the basin with swelling subsiding sequentially downslope and downstream. The results indicate that a shallow hillslope flow dominates during the wet season, but this alone is insufficient to explain shallow ground water storage in superficial valley deposits lasting into the late wet season and dry season. We conclude that InSAR signals can provide a qualitative insight in the storage and release mechanisms at a basin scale, thus complementing sparse point-scale measurements.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70214","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integral Modelling Approach for Hyporheic Exchange due to Porous Log Jams: Comparison With Experiments and Sensitivity Studies","authors":"Finn Amann,&nbsp;Jörg Lewandowski,&nbsp;Reinhard Hinkelmann","doi":"10.1002/hyp.70192","DOIUrl":"https://doi.org/10.1002/hyp.70192","url":null,"abstract":"<p>Hydrodynamic models of surface water (SW)–porewater (PW) interactions often rely on coupled modelling approaches that may not be suitable for coarser sediments and flow through structures such as log jams. SW–PW interactions play a critical role in maintaining the ecological health of rivers by enhancing biogeochemical activity within the hyporheic zone. In the present study, we applied an integral modelling approach to investigate for the first time the hyporheic exchange caused by a channel-wide porous log jam (PLJ). First, a previously conducted laboratory experiment was replicated. A very good agreement was obtained for flow dynamics, such as water depth differences, surface flow velocities, SW–PW interactions, and subsurface flow paths. For hyporheic exchange flow (HEF) patterns, the model performed well at low Froude numbers. However, for cases with higher Froude numbers, limitations emerged due to the model's two-dimensional discretisation, which obstructs flow uniformly across the width. An investigation of higher flow velocities revealed a logarithmic relationship between HEFs and Froude number. At higher flow rates, a linear decrease in HEFs was observed with increasing Froude numbers. Further analysis of the PLJ's effective porosity demonstrated an exponential decay in water depth difference between upstream and downstream, which was also reflected in the HEF rate. The study showed that the integral modelling approach serves as a robust basis for future studies of porous flow obstacles, although the relatively high computational demand has to be taken into account.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70192","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human-Induced Hydrological Droughts in Central Vietnam: A Study for River-Segment Analysis","authors":"Binh Quang Nguyen,&nbsp;Sameh A. Kantoush,&nbsp;Thanh-Nhan-Duc Tran,&nbsp;Tetsuya Sumi","doi":"10.1002/hyp.70206","DOIUrl":"https://doi.org/10.1002/hyp.70206","url":null,"abstract":"<div>\u0000 \u0000 <p>The number of drought studies is increasing due to rising concerns about risk-informed agriculture and water resource management. However, while most of this information is derived from meteorological variables, the literature on human-induced drought for river segments is limited, especially in the tropical monsoon region. In this study, we quantify human-caused hydrological droughts in segments of the Vu Gia Thu Bon (VGTB) River basin in Central Vietnam. Our objective is to gain a deeper understanding of how human activities have altered the frequency, severity and duration of hydrological droughts between 1980 and 2020 and their impacts on freshwater supply and ecosystem sustainability. Specifically, we use the Soil and Water Assessment Tool (SWAT) to obtain hydrological outputs, along with the Standardised Runoff Index (SRI), Probability Density Function (PDF) and Cumulative Distribution Function (CDF) for dry conditions analysis. Based on the examination of drought patterns over the Vu Gia and Thu Bon rivers using the proposed river-segment analysis and reconstructed streamflow, we found a contrast in drought conditions between the Vu Gia (+28.9%) and Thu Bon (−26.4%) rivers. The Vu Gia River experienced more dry conditions and drought events from 2011 to 2020 compared to the Thu Bon River. In contrast, the Thu Bon River experienced more moderate to extremely wet conditions during the same period. In addition, drought has caused saltwater intrusion to increase in intensity and duration, resulting in an 11.8% reduction in rice paddies' area from 2010 to 2020. This study highlights our approach to measuring temporal and spatial changes over river segments, providing deeper insights into water transfers and their changes across river tributaries, linking with saltwater intrusion and land use and land cover (LULC) changes.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Groundwater-Pond Interactions on a Remote Sand Island Driven by Oceanic and Meteorologic Processes","authors":"Sarah E. Hall,&nbsp;Julia A. Cantelon,&nbsp;Scott J. Ketcheson,&nbsp;Barret L. Kurylyk","doi":"10.1002/hyp.70215","DOIUrl":"https://doi.org/10.1002/hyp.70215","url":null,"abstract":"<p>Islands are hotspots of cultural and biological diversity; however, small-island populations and ecosystems face freshwater insecurity. Fresh <i>surface water</i> bodies on small islands are particularly limited in size and number and are less well studied than underlying freshwater lenses. Small islands with permeable geology often have a hydraulic connection among the ocean, groundwater system, and fresh surface water bodies, but these subsurface hydraulic linkages are poorly understood. Utilising in situ hydrologic and thermal monitoring and remote sensing, this study investigated how meteorologic (precipitation and evapotranspiration) and oceanic (waves, storm surge, and flooding) forcing drive pond level dynamics and groundwater–surface water interactions on a remote sand island (Sable Island) in the Northwest Atlantic. Stilling wells, piezometers, and sediment temperature rods were installed in five ponds from July 2020 to September 2021 and were collectively used to create area-depth relationships, infer pond bed hydraulic conductivity, and calculate vertical groundwater fluxes. PlanetScope satellite images during this period were classified to quantify pond surface areas and provide a link to in situ monitoring to assess changes following meteorologic and oceanic events. Meteorological and coastal hydrodynamic data were used to determine drivers controlling pond levels and groundwater–surface water exchange rates. Findings reveal that pond levels and vertical exchange fluxes are influenced by tides, precipitation, waves, and beach flooding, but have the highest correlation to oceanic forcing (high significant wave heights) that drive beach flooding and groundwater level changes. Remote sensing paired with pond level–area relationships proved effective for monitoring surface water dynamics in this remote area. Results expand our understanding of small-island hydrology and hydraulics and emphasise that surface water, groundwater, and the ocean are not separate but exist along a coupled hydrologic continuum. In a period of rapid environmental change, understanding fresh surface water dynamics on small islands is crucial to protecting vulnerable ecosystems from freshwater scarcity.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70215","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of Vegetation Restoration on Hillslope Hydrological Processes Under Climate Change in the Taihang Mountains, China","authors":"Bo Guo,&nbsp;Hui Yang,&nbsp;Chunyu Zhu,&nbsp;Jiansheng Cao,&nbsp;Yanjun Shen","doi":"10.1002/hyp.70213","DOIUrl":"https://doi.org/10.1002/hyp.70213","url":null,"abstract":"<div>\u0000 \u0000 <p>The Taihang Mountains serve as an ecological barrier and headwater, playing a critical role in maintaining ecological balance and water security for the North China Plain. In recent decades, this region has experienced significant vegetation greening, accompanied by a decline in water resources. Hillslopes are the fundamental units for understanding how vegetation restoration influences local hydrological processes. However, the hydrological impacts of vegetation restoration at the hillslope scale remain poorly quantified. Based on observational experiments and the Brook90 eco-hydrological model, we simulated hillslope hydrological processes from 1991 to 2023, quantifying the effects of vegetation restoration on eco-hydrological processes in mountainous areas. The results indicated that (1) from 1991 to 2023, the average evapotranspiration, transpiration, and interception loss at the observation site were 441.1, 321.6, and 58.3 mm, respectively. Evapotranspiration, transpiration, and interception loss showed increasing trends, with cumulative increases of 112.0, 107.7, and 17.5 mm, respectively, while soil evaporation decreased by a cumulative total of −12.3 mm. (2) Vegetation restoration contributed to the increasing trends in evapotranspiration, transpiration, and interception loss, with cumulative contributions of 16.5, 36.4, and 21.9 mm, respectively. (3) Vegetation restoration increased evapotranspiration, driven mainly by transpiration and interception loss, while reducing soil water storage and runoff, highlighting its significant impact on water availability. Long-term quantitative observations of hillslope hydrological processes help to understand the decline in water yield due to vegetation recovery in mountainous areas. These findings offer crucial guidance for improving water conservation strategies and selecting afforestation species.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144657669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial and Temporal Variability in Event Water in Near-Surface Flow Pathways in a Humid Steep Headwater Catchment","authors":"Anna Leuteritz,&nbsp;Victor Aloyse Gauthier,&nbsp;Ilja van Meerveld","doi":"10.1002/hyp.70186","DOIUrl":"https://doi.org/10.1002/hyp.70186","url":null,"abstract":"<p>In steep humid catchments with low permeability soils, lateral flow at, or near, the soil surface is an important runoff generation mechanism. However, so far, few studies have investigated near-surface runoff for vegetated hillslopes in temperate climates. To better understand the relative importance of rainfall (event water) to near-surface flow in pre-Alpine headwater catchments underlain by gleysols, we installed 14 small (1 m wide) runoff plots across the Studibach catchment and collected samples of overland flow and lateral subsurface flow in the topsoil (i.e., topsoil interflow), soil water, groundwater and rainwater during the snow-free seasons of 2021 and 2022. The samples were analysed for the stable isotopes of hydrogen and oxygen and used in a mixing model to infer the importance of soil water (i.e., pre-event water) and rainfall (i.e., event water) for overland flow and topsoil interflow. The spatial and temporal variability of the event water fractions was high. Event water was the dominant source (&gt; 50%) for nearly half of the overland flow samples and almost 40% of all topsoil interflow samples. The best predictors for the event water fractions in overland flow and topsoil interflow were, according to a random forest model, the duration of the rainfall event, the rainfall intensity, and the antecedent wetness conditions. The event water fractions were not clearly related to site characteristics. These findings show that overland flow and topsoil interflow consist of a mixture of rainwater and soil water and that the relative contribution of rainwater depends on the complex interplay between antecedent soil moisture conditions, rainfall event characteristics and site characteristics. These results have large implications for the interpretation of the event water fractions in streamflow and related inferences about the dominant runoff generation mechanisms.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scaling Up Bark Hydrology: Tree Size and Functional Traits Shape Water Storage in a Tropical Cloud Forest","authors":"Kelly Cristina Tonello,&nbsp;Juliano Carvalho de Oliveira,&nbsp;Roberto Starzynski,&nbsp;Sergio Dias Campos","doi":"10.1002/hyp.70211","DOIUrl":"https://doi.org/10.1002/hyp.70211","url":null,"abstract":"<p>Bark has long been overlooked as a component of forest water cycling, particularly in fog-dependent tropical montane cloud forests (TMCFs). Here, we quantified the water absorption capacity of bark in 17 tree species from a Brazilian TMCF and evaluated how functional traits and tree size influence bark water uptake (BWU) at the whole-tree scale. Bark samples were saturated in the lab, and field data were used to estimate water uptake per tree. While BD and BWSC showed limited interspecific variation, BWU varied greatly, mainly due to bark volume (Vb). A multiple regression model explained 89.5% of the variation in BWU. Sensitivity and bootstrapping analyses confirmed that, although Vb was the dominant predictor, functional bark traits (BD and BWSC) also contributed significantly to water uptake. These findings highlight that BWU is shaped by both structural and functional traits, underscoring a dual control on bark hydrology. Critically endangered (<i>Araucaria angustifolia</i>) and ecologically dominant (<i>Senna multijuga</i>) species exhibited the highest water storage per tree. Although the absolute values represent the potential maxima under laboratory conditions, the comparative data provide insights into species-level contributions to forest water dynamics. Notably, bark water uptake may help maintain moisture availability during dry spells or fog-free intervals, particularly in ecosystems where rainfall is intermittent and canopy-dwelling organisms depend on sustained humidity. Our results suggest that bark traits should be more explicitly considered in hydrological models and conservation planning for TMCFs under changing climate regimes.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70211","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Changing Flood Patterns in the Yangtze River: Roles of Climate, Dam Regulation, and Urbanization in Altering Hydrological Processes","authors":"Yang Xiao,&nbsp;Ran Gu,&nbsp;Chen Xu,&nbsp;Taotao Zhang,&nbsp;Zixuan Wang,&nbsp;Yao Yao,&nbsp;Jiaming Liu","doi":"10.1002/hyp.70201","DOIUrl":"https://doi.org/10.1002/hyp.70201","url":null,"abstract":"<div>\u0000 \u0000 <p>The middle and lower reaches of the Yangtze River (MLYR), China's most flood-prone region, have experienced significant changes in flood regimes under climate change and intensive human activities. To elucidate the hydrological processes driving these changes, this study combined a random forest model with the Mann–Kendall test to analyse flood characteristics and influential factors. Results reveal: (1) Abrupt flood stage declines post-2003 (Three Gorges Dam operation) followed by increases post-2016, primarily due to urbanisation amplifying runoff and accelerating drainage discharge into river channels; (2) concentration of flood peaks in July, driven by reservoir-induced baseflow elevation synchronising with intensified monsoon rainfall; (3) Spatial heterogeneity in flood severity, where middle reaches face high-magnitude floods from flow convergence, while lower reaches experience frequent inundation due to tidal-urban interactions. Mechanistically, we demonstrate how dam operations redistribute flood risk (e.g., prolonging high stages in Dongting Lake) and urbanisation reconfigures flood pathways, converting pluvial to fluvial flooding. These findings underscore non-stationary flood dynamics in regulated basins globally, necessitating adaptive strategies integrating real-time morphodynamic feedbacks and nature-based urban water retention. This study advances hydrological understanding of how human infrastructure and climate interact to reshape flood processes in large river systems.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tracing Vegetation Resilience and Recovery Pathways to Drought Through Time Series Decomposition","authors":"Syed Bakhtawar Bilal,&nbsp;Vivek Gupta","doi":"10.1002/hyp.70208","DOIUrl":"https://doi.org/10.1002/hyp.70208","url":null,"abstract":"<div>\u0000 \u0000 <p>India's vegetation dynamics are highly sensitive to water stress, with meteorological droughts posing significant risks to ecosystems and agriculture. Understanding the interaction between drought and vegetation health remains a critical challenge. Existing methods for analysing vegetation trends often fail to accurately capture abrupt changes in vegetation health and their relation with drought periods, limiting our understanding of how vegetation responds to water stress. This study introduces an integrated approach that combines the Breaks For Additive Season and Trend (BFAST) methodology with drought metrics to examine vegetation responses across various land cover types in India. Compared to other conventional methods for detecting trends and breakpoints in a time series, BFAST does not assume a rigid trend or seasonal trajectory. This flexibility allows it to identify abrupt breaks in vegetation health, which are often overlooked in traditional analyses. The identified breaks, trends, and seasonal patterns are then examined to determine the timing, magnitude, and frequency of changes in NDVI, correlating them with drought responses identified using the Standard Precipitation Index (SPI). Findings indicate that arid and semi-arid regions in India experience the highest overlap between drought occurrences and negative NDVI transition points, periods where vegetation health shows a significant decline; therefore, highlighting a heightened vulnerability to water stress. Conversely, agriculturally intensive regions like the Indo-Gangetic Plain demonstrate greater resilience. Seasonal analysis suggests that vegetation health is closely tied to monsoon variability, with most breaks occurring during peak monsoon months. Additionally, analysis of the post-drought period revealed that the vegetation response is highly sensitive to precipitation deficits during the recovery period following a drought.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"39 7","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144635248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}