Hydrological Processes最新文献

{"title":"Investigating Spatial Heterogeneity of Karst Water Storage Capacity and Nonclosure of Underground Watersheds in Karst Hydrological Simulation","authors":"Zeling Ren,&nbsp;Binquan Li,&nbsp;Yang Xiao,&nbsp;Kuang Li","doi":"10.1002/hyp.70012","DOIUrl":"https://doi.org/10.1002/hyp.70012","url":null,"abstract":"<div>\u0000 \u0000 <p>Karst landforms interfere with the runoff generation and confluence process, resulting in generally poor hydrological simulation accuracy in karst watersheds. We proposed a new karst hydrological module, which has two cores. One is the karst water storage capacity distribution curve that represents the distribution of runoff generation thresholds in karst areas, and the other is the underground nonclosure coefficient that represents the nonclosure phenomenon of underground watersheds in karst areas. The new module was further coupled with the Xinanjiang rainfall–runoff (XAJ) model to establish a complete hydrological model for karst areas (referred to as XAJ-karst model). The sensitivity of the XAJ-karst model parameters was analysed using the Sobol method, and applied to a typical karst watershed in Guizhou Province, China, to test the model performance on daily and hourly time scales. In addition, we also explored the impact of dynamic changes in the nonclosure coefficient of underground watershed area in karst watersheds on model results. Results showed that the average value of Kling–Gupta efficiency (KGE) of the XAJ-karst model on the daily and hourly time scales was 0.85 and 0.77, respectively. In comparison with the XAJ model, the average KGE value of the XAJ-karst model on both daily and hourly scales improved by 10.8% and 6.4%, respectively, demonstrating better simulation accuracy. In addition, there is a underground nonclosure phenomenon in the Xiangyang watershed, and the actual area of underground watershed expands abruptly as the antecedent-precipitation increases to the critical value. Moreover, the water storage and hysteresis effects of the karst landform result in a certain hysteresis in water exchange between the underground watershed and adjacent watersheds.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 12","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142763994","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":"Quantitative Classification of Spring Discharge Patterns: A Cluster Analysis Approach","authors":"Magdalena Seelig,&nbsp;Simon Seelig,&nbsp;Matevž Vremec,&nbsp;Thomas Wagner,&nbsp;Heike Brielmann,&nbsp;Jutta Eybl,&nbsp;Gerfried Winkler","doi":"10.1002/hyp.15326","DOIUrl":"https://doi.org/10.1002/hyp.15326","url":null,"abstract":"<p>Springs provide critical water resources that are sensitive to changing climate and catchment processes. In many regions, understanding the temporal variability and spatial distribution of spring discharge is therefore crucial for sustainable water management. Knowledge of these discharge characteristics, organised in a coherent framework, is essential for protecting spring water and preventing shortages. To establish such a framework, we conducted a comparative analysis of long-term discharge records from 96 springs across Austria. Based on discharge seasonality and autocorrelation, we derived a broad-scale classification through cluster analysis and explored associations between individual clusters. The identified similarities in discharge patterns were grouped into four distinct spring categories, each demonstrating common behaviour. To determine the main factors influencing discharge across these four groups, we compared their spatial and temporal patterns with regional climate and catchment characteristics. They align with physical drivers of spring discharge, including precipitation frequency and intensity, snow cover duration, and dominant aquifer type. As these factors were not included in the classification procedure, their alignment supports the validity of our statistical approach. We conclude that the quantitative information derived from this analysis provides a valuable complement to traditional spring classification schemes, which are often based on qualitative knowledge. Our proposed strategy refines these classification approaches, enhances objectivity and reproducibility, and promotes conformity across hydrological disciplines.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 12","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.15326","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142763993","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":"Effects of Different Spatial Distributions of Vegetation on the Hydraulic Characteristics of Overland Flow","authors":"Chengzhi Xiao,&nbsp;Xiang Liu,&nbsp;Luqiang Ding,&nbsp;Nan Zhu,&nbsp;Zihan Wang","doi":"10.1002/hyp.70016","DOIUrl":"https://doi.org/10.1002/hyp.70016","url":null,"abstract":"<div>\u0000 \u0000 <p>Vegetation plays a crucial role in mitigating and controlling soil erosion caused by overland flow. However, variations in the hydraulic characteristics of overland flow induced by the spatial distribution of vegetation with different row and column spacings are often overlooked in existing literature, potentially leading to significant deviations in predicting these characteristics. In this study, 180 lab-scale runoff tests were conducted to clarify the hydraulic characteristics of overland flow considering six <i>α</i> (the ratio of the lateral distance of vegetation to stem diameter) levels, six <i>β</i> (the ratio of the slope distance of vegetation to stem diameter) levels, and three slope angles (<i>θ</i>) under five flow discharges (<i>Q</i>) conditions. The results show that the observed flow regime of overland flow belongs to the transition flow regions, shifting from slow to rapid as <i>α</i> and/or <i>β</i> increase. The friction coefficient and the proportion of frictional resistance in the total flow resistance increase with increasing <i>α</i> and <i>β</i>. The local resistance dominates the total flow resistance of bare glass slopes. The local resistance coefficient <i>ξ</i> decreases with increasing <i>α</i> and <i>β</i>, however, it initially increases and then decreases with increasing <i>θ</i>. The impact of <i>β</i> on the local resistance is greater for gentle slopes, whereas the impact of <i>α</i> is more significant for steep slopes. <i>ξ</i> exhibits a negative correlation with <i>Re</i> and the <i>ξ</i>-<i>Re</i> curves gradually level off as <i>α</i> or <i>β</i> increases, while they become steeper with increasing <i>θ</i>. A prediction model for the total flow resistance was established taking into account the combined effects of <i>Re</i>, <i>α</i>, <i>β</i> and <i>θ</i>, which provides better prediction performance than two other relevant models. The results obtained from this study provide valuable insights into the hydraulic characteristics of overland flow and offer clear guidance for vegetation management in controlling soil erosion on slopes with heterogeneous vegetation coverage.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 12","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142764267","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":"Modelling Seasonal Variability in Parameters Defining Volumetric Water Content in a Low Permeability Soil in Central Illinois: An Application of MODFLOW-6 and the Unsaturated Zone Flow Package","authors":"Michael P. Krasowski,&nbsp;Esra Gulsen,&nbsp;Allan E. Jones,&nbsp;Daniel B. Abrams","doi":"10.1002/hyp.70007","DOIUrl":"https://doi.org/10.1002/hyp.70007","url":null,"abstract":"<p>Increasing interest in solute transport phenomena in agricultural systems on a sub-annual basis necessitates a better understanding of seasonal changes in natural systems and how these changes can be incorporated into modelling. A better understanding of the seasonal timing of nutrient loading in tile drained agricultural systems in particular is essential for efforts trying to replicate or predict the occurrence of harmful algal blooms. Literature exists showing there are seasonal dynamics (freeze–thaw, plant-root processes, land management practices, etc.) that may cause changes in the hydraulic properties of the soil zone including hydraulic conductivity and porosity. To test whether these changes are important in an agricultural system, a MODFLOW-6 model using the unsaturated zone flow package was constructed. The simulation was comprised of separate, seasonal models to be run sequentially with each year being broken into a winter and summer seasons. As part of this architecture, model parameters representing soil hydraulic properties were allowed to vary by season. The model was calibrated against soil moisture observations at multiple depths using a genetic algorithm machine learning technique. The parameters of the sub-models were compared for the winter and summer seasons. Brook-Corey epsilon, saturated vertical conductivity, saturated volumetric water content and residual volumetric water content were found to be consistently different between the modelled summer and winter periods. A more traditional model which did not allow hydraulic properties to vary seasonally was also run and compared to the seasonal architecture and the seasonal architecture was found to improve simulation results. The hydrologic dynamics of the unsaturated zone—particularly in tile drained agricultural systems—control the residence time for water and solutes, which is critical for in-field chemical processes such as denitrification. This work has important implications for seasonal transport phenomena in agricultural systems and improving the simulation and prediction of harmful algal blooms.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737374","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":"Microscopic Mechanism of Particle Clogging in Porous Media During Managed Aquifer Recharge: From X-Ray Computed Tomography (CT) Imaging to Numerical Modelling","authors":"Yang Xu,&nbsp;Xueyan Ye,&nbsp;Xinqiang Du","doi":"10.1002/hyp.70002","DOIUrl":"https://doi.org/10.1002/hyp.70002","url":null,"abstract":"<div>\u0000 \u0000 <p>Managed aquifer recharge (MAR) is a strategy within water resources management. However, issues related to clogging have hindered its implementation. The change in permeability of the medium is significantly influenced not only by the macroscopic characteristics of infiltration sand, such as heterogeneity and anisotropy, but also by its microstructural features, including pore structure, morphology and connectivity. Nevertheless, the interactions between fluid flow, particle migration and changes in permeability remain unclear. This study investigates the pore-scale response mechanisms between fluid flow and pore clogging using a non-destructive x-ray computed tomography approach. Our findings indicate that the decrease in permeability due to particle deposition occurs in stages, with particles preferentially accumulating in irregularly shaped pores. The changes in the permeability of the sand column exhibit a negative correlation with alterations in shape factor and tortuosity, while showing a positive correlation with the fractal dimension. As pores become clogged with particles, the increase in tortuosity leads to a longer flow path. Once the sharp edges of the irregular pores are filled with particles, the pore space becomes smoother and more uniform, and the fractal dimension of the pores gradually decreases with further clogging. Based on numerical modelling of particle movement and the clogging process in porous media, it was determined that pressure is greatest in clogged pores. When this pressure reaches a certain threshold, the particles that were previously trapped in the pores are flushed out, leading to uneven changes in normalised hydraulic conductivity and normalised concentration at the outlet. If the pressure is insufficient to dislodge the clogging particles, the water flow path is compelled to change, resulting in a gradual stabilisation of the clogging.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737455","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":"Quantifying Hydraulic Geometry and Whitewater Coverage for Steep Proglacial Streams to Support Process-Based Stream Temperature Modelling","authors":"A. L. Dufficy,&nbsp;B. C. Eaton,&nbsp;R. D. Moore","doi":"10.1002/hyp.70003","DOIUrl":"https://doi.org/10.1002/hyp.70003","url":null,"abstract":"<p>At-a-station hydraulic geometry (AASHG) relationships describe the dependence of a river's width, mean depth and mean velocity on discharge at a given location, and are typically modelled as power-law functions. They are often used when modelling stream temperature under unsteady flow conditions. Deriving AASHG relationships is challenging for steep proglacial streams due to the combination of complex morphology and velocity distributions, and rapidly varying flow. The objective of this study was to combine tracer injections with drone-based photogrammetry to derive AASHG relationships for a steep proglacial channel and to quantify whitewater coverage and its relationship with discharge to support process-based stream temperature modelling. Velocity–discharge and width–discharge relationships were reasonably well characterised using power-law functions, but varied amongst sub-reaches. Whitewater coverage as a fraction of total stream surface area generally exceeded 50% for the range of flows sampled, and exhibited a statistically significant positive relationship with discharge, which varied amongst sub-reaches. For the range of flows captured during drone flights, the relationship could be represented by a linear function. However, an asymptotic model would be required to extend the relationship to higher flows. The magnitude of whitewater coverage indicates that the albedo of the stream should be substantially higher than values typically used in stream temperature models, and the relationship with discharge means that ongoing glacier retreat, and the associated reduction in summer discharge, should result in lower albedo and higher downstream warming rates, reinforcing the effects of decreasing velocity and mean depth as flows decline.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737456","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":"Snow Depth Distribution in Canopy Gaps in Central Pyrenees","authors":"Francisco Rojas-Heredia,&nbsp;Jesús Revuelto,&nbsp;César Deschamps-Berger,&nbsp;Esteban Alonso-González,&nbsp;Pablo Domínguez-Aguilar,&nbsp;Jorge García,&nbsp;Fernando Pérez-Cabello,&nbsp;Juan Ignacio López-Moreno","doi":"10.1002/hyp.15322","DOIUrl":"https://doi.org/10.1002/hyp.15322","url":null,"abstract":"<p>This research analyses the snow depth distribution in canopy gaps across two plots in Central Pyrenees, to improve understanding of snow–forest and topography interactions. Snow depth maps, forest structure–canopy gap (FSCG) characteristics and topographic variables were generated by applying <i>Structure from Motion</i> algorithms (SfM) to images acquired from Unmanned Aerial Vehicles (UAVs). Six flights were conducted under different snowpack conditions in 2021, 2022 and 2023. Firstly, the snow depth database was analysed in terms of the ratio between the radius of the canopy gap and the maximum height of the surrounding trees (<i>r</i>/<i>h</i>), in order to classify the gaps as <i>small-size</i>, <i>medium-size</i>, <i>large-size</i>, or <i>open areas</i> at both sites independently. Then Kendall's correlation coefficients between the snow depth, FSCG and topographic variables were computed and a Random Forest (RF) model for each survey was implemented, to determine the influence of these variables in explaining snow depth patterns. The results demonstrate the consistency of the UAV SfM photogrammetry approach for measuring snowpack dynamics at fine scale in canopy gaps and open areas. At the northeast exposed Site 1, the larger the <i>r</i>/<i>h</i> observed, the greater was the snow depth obtained. This pattern was not evident at the southwest exposed Site 2, which presented high variability related to the survey dates and categories, highlighting the relevance of topography for determining optimum snow accumulation in forested areas. <i>Slope</i> systematically exhibited a negative and significant correlation with snow depth and was consistently the highest-ranked variable for explaining snow distribution at both sites according to the RF models. <i>Distance to the Canopy Edge</i> also presented high influence, especially at Site 1. The findings suggest differences in the main drivers throughout each site and surveys of the topographic and FSCG variables are needed to understand snow depth distribution over heterogeneous mountain forest domains.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.15322","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737454","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":"Rapid Hydrological Responses Following Process-Based Restoration in a Degraded Sierra Nevada Meadow","authors":"Emma C. Sevier,&nbsp;Karen L. Pope,&nbsp;David N. Dralle,&nbsp;Joseph W. Wagenbrenner,&nbsp;Adam K. Cummings,&nbsp;Paul Richardson,&nbsp;Margaret Lang","doi":"10.1002/hyp.70005","DOIUrl":"https://doi.org/10.1002/hyp.70005","url":null,"abstract":"<div>\u0000 \u0000 <p>Mountain meadows are ecologically important groundwater dependent ecosystems that retain and store water in upland forested landscapes. They tend to occur in low gradient, broad valleys where water slows and sediment accumulates, making them efficient locations for restoration. Over a century and a half of land use has degraded many meadows in the Sierra Nevada, reducing their hydrological and ecological functionality. Process-based restoration (PBR) is an ecosystem rehabilitation approach that utilises biogeomorphic processes to facilitate functional ecosystem recovery. Low-tech applications of PBR leverage fluvial processes, plant growth and the manipulation of onsite materials to increase structural and hydrological complexity. In meadows, typical goals associated with restoration are to increase groundwater elevations, expand wetted area, encourage sediment capture and create diffuse flow paths leading to improved ecological function over time. This study compares surface and groundwater conditions in a degraded riparian meadow in the Sierra Nevada, California, USA for 1 year before and after process-based restoration to understand initial changes in meadow hydrogeomorphic function. Restoration included the installation of 39 postless beaver dam analog structures in ~1 km of incised meadow channel. Stage-discharge data at the inlet and outlet of the project area were paired with groundwater data collected from 13 wells distributed across the meadow to estimate increased water storage of 3700 m³ due to restoration. After the wet winter of 2023, we estimated that pools upstream of structures filled to over half their volume with fine sediment. We also applied hydrodynamic modelling to evaluate fluvial changes at high flows and found that restoration increased flow complexity and wetted surface area. These short-term responses highlight the potential speed and ability of low-tech, process-based restoration in achieving restoration outcomes.</p>\u0000 </div>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737457","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":"Advancing Hydrologic Modelling Through Bias Correcting Weather Radar Data: The Valgrosina Case Study in the Italian Alps","authors":"Andrea Citrini,&nbsp;Georgia Lazoglou,&nbsp;Adriana Bruggeman,&nbsp;George Zittis,&nbsp;Giovanni P. Beretta,&nbsp;Corrado A. S. Camera","doi":"10.1002/hyp.15339","DOIUrl":"https://doi.org/10.1002/hyp.15339","url":null,"abstract":"<p>The urgency of understanding the intricate input–output relationships of the hydrologic cycle is amplified by the accelerating climate change impacts in mountain environments. This study focuses on optimising water resource management of a dammed valley in the Central Alps (Northern Italy). The research aims to integrate radar data and precipitation interpolation techniques (TIN, Copula, cumulative distribution function; CDF techniques, inverse distance weighting; IDW, thin plate spline; TPS, ordinary kriging; OK and detrended kriging; DK) into a semi-distributed hydrologic model, by utilising hourly precipitation data from 22 rain gauges and a composite weather radar product spanning 2010–2020. Two main objectives were pursued: (i) to develop and evaluate various radar precipitation correction methods against a benchmark dataset and (ii) to calibrate and assess the performance of the GEOFrame hydrologic model forced with corrected precipitation input. Point-based and spatial correction approaches were evaluated against ground measurements through leave-one-out tests. The former derives dependence functions between the biased radar series and those of the closest three rain gauges to the target point applying a triangular irregular network. The latter combines deterministic and geospatial interpolations to the rain gauge/radar residuals to derive a corrected surface by incorporating radar values as trends. Precipitation series exceeding the composite scaled score of the benchmark dataset were used as input for hydrologic modelling. The spatial method combining radar values with ordinary kriging provided the best results for both correction and modelling (hourly KGE &gt; 0.75). The spatial approaches proved easier to apply than the point-based methods. In addition, correcting precipitation significantly improved low-flow simulation from negative hourly lnNSE to values greater than 0.25. As a further step, given the overall good performance of the spatial methods, they could be used operationally as an ensemble to analyse management scenarios.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.15339","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708378","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":"The Effects of Bedrock Topography and Soil Permeability on Saturated Zone Distribution in a Mountainous Steep-Slope Area","authors":"Kotaro Yanai,&nbsp;Naoya Masaoka,&nbsp;Ken'ichirou Kosugi,&nbsp;Masamitsu Fujimoto,&nbsp;Yosuke Yamakawa","doi":"10.1002/hyp.70000","DOIUrl":"https://doi.org/10.1002/hyp.70000","url":null,"abstract":"<p>Saturation development and distribution at the soil–bedrock interface are important for predicting shallow landslide occurrence. Previous studies have indicated that saturation is generated in bedrock depressions and valleys and that bedrock groundwater seepage generates locally saturated areas. However, the effects of soil permeability, which is known to be heterogeneously distributed, on saturation development and distribution are poorly understood. In this study, we performed unprecedented high-resolution (approximately 50 cm grid) soil pore water pressure and soil temperature monitoring using 141 tensiometer–thermocouple sets in a plot measuring approximately 5 × 4 m to investigate the effects of topography and bedrock groundwater seepage on saturation development and distribution. We then measured permeability distribution of two soil profiles, including at the soil–bedrock interface, using the Guelph Permeameter method (GP method) for comparison with saturated zone distribution and saturation duration. The results indicated that a perennial saturated area was formed by bedrock groundwater seepage and was distributed downstream from a certain bedrock surface altitude in the lower region of the study plot. After a peak of rainfall, the perennial saturated area expanded upslope owing to the increased seepage. In areas without the influence of bedrock groundwater, saturation was observed to retreat rapidly at high permeability points and persist over long periods at low permeability points; however, the saturation duration was inconsistent with the bedrock surface topography. Therefore, it is suggested that the bedrock altitude controls the saturation distribution generated by bedrock groundwater, whereas the distribution of saturation that is associated with direct rainwater infiltration may be controlled by the permeability distribution during recession periods. Although the plot size was small, the unprecedented high-resolution observations suggest that the permeability distribution, rather than the bedrock topography, may control the saturated zone distribution following rainfall.</p>","PeriodicalId":13189,"journal":{"name":"Hydrological Processes","volume":"38 11","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hyp.70000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708379","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}