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Restoration engineering measures, such as managed realignments or building groins, modify the environmental characteristics of coastal intertidal ecosystems. Creating physical modifications that are beneficial to an intertidal system's ecology necessitates an in‐depth understanding of the relationships between the abiotic and biotic components of a given intertidal habitat. In this study, we evaluate how hydrodynamics and sediment characteristics drive the development of the benthic macrofauna community during the first 5 years following engineering measures to enhance benthic macrofauna diversity at three locations. The creation of low‐energy habitats through groins (Knuitershoek and Baalhoek) and a managed realignment dike breach (Perkpolder) led to the accumulation of fine sediments in all three impact sites. Biomass of benthic macrofauna quickly increased between 2016 and 2020, with successional processes being more important in Perkpolder, where the habitat was started completely from scratch due to a managed realignment, than at Knuitershoek or Baalhoek, where habitat conditions were improved by adding groins. In addition, the density of benthos‐eating birds, especially oystercatchers, increased at some of the modified sites. While a low‐energy habitat may harbor more diverse assemblages of benthic macrofauna than a highly dynamic one, the extremely high silt content, which is typical for low‐energy habitats, may slow benthic community development. The observed increase of biomass at our impact sites highlights the value of the interventions, while the delays in the response of the benthic macrofauna community emphasizes the need for extensive monitoring both in time and space and the identification of underlying abiotic–biotic mechanisms. [ABSTRACT FROM AUTHOR]

The northern slope of Mount Merbabu exhibits a volcanic landform with the possibility of spring formation, which can be analyzed using a hydrogeomorphological methodology. The objective of this study was to examine the hydrogeomorphological features of springs, including their physical attributes such as appearance, distribution, discharge, flow parameters, temperature, pH, total dissolved solids (TDS), and electrical conductivity. This research methodology involved the collection of primary data through the observation of specific geographical sites and the deliberate selection of sampling areas. The research findings indicated the presence of 30 spring locations on the northern slope of Mount Merbabu. These springs were found in various landform units, such as craters, cones, slopes, feet, plains, and volcanoes. The main numerical results indicated that the springs exhibited a wide range of discharge rates from 0.02 to 33.29 liters per second, temperature variations from 21.9 to 23.24 degrees Celsius, pH levels from 3.57 to 7.01, TDS values from 38 to 521 mg/L, and electrical conductivity from 40 to 814 µS/cm. The main conclusions were that these springs significantly contributed to the local water resources, with potential applications for agricultural and domestic use. However, the study was limited by the seasonal variations. The scientific novelty of this study lays in its comprehensive analysis of the hydrogeomorphological characteristics of these springs, which were previously undocumented. This research bridged a crucial gap in understanding the interactions between geological formations and spring water quality and quantity, offering valuable data for sustainable water resource management and conservation strategies. [ABSTRACT FROM AUTHOR]

The role of riparian vegetation in driving hydrogeomorphic development within rivers is increasingly recognised. Vegetation-mediated biotic-abiotic interactions are known to become dominant as landscapes develop, however to date the timescales and rates of these interactions remain poorly understood. Here, we outline how our ongoing research of river development in Glacier Bay National Park has allowed us to observe and quantify the role of instream wood in driving biotic-abiotic feedback mechanisms over a large spatiotemporal scale. Our research shows that the colonisation of riparian areas with small, relatively simple woody material (predominantly alder and willow boles) and its subsequent introduction into the river channel initiates the creation of hydrogeomorphic diversity which biotic communities are able to utilise. However, as riparian vegetation continues to develop through succession, the introduction of increasingly large and complex material (spruce and hemlock trees) exerts increasing control on instream conditions. This review highlights the role of instream wood in increasing river-terrestrial interactions, and incorporates instream wood into previous conceptual models related to fluvial biogeomorphological succession and ecosystem development within Glacier Bay. [ABSTRACT FROM AUTHOR]

The current focus of river restoration on flow and sediment transfer without proper consideration of vegetation as a key structuring agent, beyond its stabilising effect, is too simplistic. We contend that vegetation has an essential role in shaping the physical fluvial environment and should be considered equally alongside hydrogeomorphic processes in restoration projects. In support, we introduce engineer plants as important controls, along with flowing water and transported sediments, on the morphodynamics of river systems and associated physical habitat development. The effect of vegetation on channel planform is then summarised, the influence of vegetation on hydrogeomorphic connectivity is outlined, and then the role of vegetation in landform development and habitat provision, as encapsulated in the fluvial biogeomorphic succession model, is described. We then present examples demonstrating how vegetation has contributed to the recovery of degraded rivers through biogeomorphic processes. Finally, we advance the concept of biogeomorphic river restoration by proposing principles to support a closer synthesis of the component sciences and list key areas for practitioners to focus on. Vegetation succession has a significance that goes beyond its physical structure or influence on sediment stability. In many river settings, it is central to channel evolution. The coupled assembly of plant communities and fluvial landforms affect the development of spatially and temporally dynamic habitat through biogeomorphic interactions. Restoration approaches that do not fully consider this dynamic may fail to anticipate river behaviour and recovery trajectories. [ABSTRACT FROM AUTHOR]

Hydrogeomorphology studies river dynamics, focusing on the interactions between flow structure, sediment transport, and the morphologies that characterize rivers and their watersheds. It provides an analytical framework and tools for better integrating knowledge of river dynamics into river management in the broadest sense, and more specifically, into river restoration as well as into the assessment and prevention of risks associated with fluvial hazards. In Quebec, hydrogeomorphology is emerging as a significant contribution to risk assessment and management approaches, and is at the heart of a paradigm shift in river management whereby process restoration aims to increase the resilience of fluvial systems and societies, and improve the quality of fluvial environments. This contribution outlines the trajectory of hydrogeomorphology in Quebec, based on scientific publications by Quebec geographers, and discusses the discipline's aims in research and knowledge integration for river management. Messages clés: Les géographes du Québec ont contribué fortement au développement des connaissances et outils de l'hydrogéomorphologie.L'hydrogéomorphologie a évolué d'une science fondamentale à une science où les connaissances fondamentales sont au service de la gestion des cours d'eau.L'hydrogéomorphologie et le cortège de connaissances et d'outils qu'elle promeut font de cette discipline une partenaire clé pour une gestion holistique des cours d'eau. [ABSTRACT FROM AUTHOR]

River typology is determined by a set of hydrological and geomorphological characteristics, which can determine the structure of aquatic macroinvertebrate communities throughout a watershed. In this study we aim to address the gap of knowledge in the classification of the typology of Neotropical rivers and determine their association with macroinvertebrate assemblages. In total, 138 sites from 107 rivers were sampled in Costa Rica, between years 2015 and 2020. Rivers were classified into V, Tr and U typologies based on the shape of the riverbed, substrates, current velocity and contact with riparian forest. The affinity of aquatic macroinvertebrate taxa to each typology was determined. The results confirmed a clear separation of the aquatic macroinvertebrate assemblages between the typologies, and we observed that some genera showed affinity to a specific typology: Macrobrachium and Caenis are related to U-type; Simulium and Anacroneuria to V-type, while Americabaetis and Thraulodes to Tr-type. This separation was related to in-stream habitat supply and substrate characteristics, yet there was an overlap of shared taxa between the V and Tr-type, and between the Tr and U-type. Our study linked 238 taxa to three river typologies, highlighting the importance of river hydrogeomorphology as a robust factor structuring the macroinvertebrate assemblages in tropical streams. River channel typology should be considered a relevant explanatory variable when studying macroinvertebrate responses, not only within ecological studies, but also for biomonitoring and risk assessment related to land use changes, pollution, or watershed management. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the processes and factors conditioning the hydrochemistry of freshwater lenses associated with Holocene coastal deposits in an area of the Argentinean Atlantic coast. For this purpose, geomorphological units were mapped and a shallow groundwater monitoring network was established, including pre-existing boreholes and shallow exploration wells. During the construction of the shallow exploration wells, sediment samples were extracted to determine the texture and mineralogical characteristics. Four samplings were carried out to measure in situ physicochemical parameters and to determine majority ions in the water. The chemical data were analysed considering the associated geomorphology, lithology, water balance and hydrodynamics. The geomorphological and lithological characteristics are the combined factors that favour the preferential rainwater recharge processes. Geoforms with greater topography and extension (continental and coastal dunes) tend to store freshwater lenses, while those with lower topography and little areal extension (sand sheets and beach ridges) have very thin lenses and tend to become salinized. Climate and local water balance are factor that determines that groundwater recharge occurs preferentially in winter. This causes increases in groundwater levels and a decrease in the groundwater EC. On the other hand, mineralogy is a factor that conditions the geochemical processes associated with the water--sediment interaction. Within the main geochemical processes, the dissolution and/or mineral weathering, the dissolution of CO2(g) and ion exchange determine the presence of different hydrochemical facies, where Ca-HCO3 facies dominates in elevated geoforms, while Na-Cl in lower ones. The results obtained in this work have provided an understanding of the factors and processes that condition groundwater chemistry in coastal deposits, being of vital importance for the management of water resources. [ABSTRACT FROM AUTHOR]

The Vakhsh River is tributary to the Amu Dayra, supporting numerous hydropower facilities as well as irrigation and community water supplies. High sediment loads are major concerns for these uses, yet little is known about the spatial distribution of the dominant sediment sources or their connectivity to fluvial systems. Here, we address this gap by combining findings from a series of field expeditions, remotely sensed climate and vegetation assessments, systematic sediment sampling, hydrograph analysis, and a review of local literature. Our preliminary findings show that various mass wasting processes (e.g., landslides, debris flows, rockfall, dry ravel, bank failures) constitute the major connected sources of sediment, particularly in the mid- to downriver reaches, many of which are unaffected by land use. Surface erosion, including the large gullies in loess deposits of the lower basin, are more affected by poor agricultural practices and road runoff, and can supply large loads of fine sediment into the river. Climate trends detected through remote sensing show an increase in rainfall in the lower half of the basin from spring to early summer while solid precipitation has increased in the eastern half in March. These trends may lead to more runoff and increases in sedimentation if they continue. [ABSTRACT FROM AUTHOR]

Habitat degradation is one of the major reasons for freshwater species decline. Hydrogeomorphological processes (such as sediment transport, bank erosion, and flooding) operate at the catchment scale and determine habitat features in river reaches. However, habitat quality indices and restoration for freshwater fish species are often implemented at small spatial scales of a few hundred metres. The Morphological Quality Index (MQI) considers fluvial processes at larger scales as well as channel forms, human impacts, and historical changes, but few studies have assessed its relevance for ecosystem health. We investigated relationships between the MQI, habitat quality (using the Qualitative Habitat Evaluation Index, QHEI), land cover, and fish metrics (number of fish species, index of biotic integrity (IBI), and trout biomass) in 26 salmonid streams in Aotearoa New Zealand and Southern Ontario, Canada. We found a significant correlation between the MQI and QHEI, and both metrics were correlated with urban and native forest proportion in the catchment. However, we found no relation between the MQI and the proportion of agricultural land in the catchment, while the QHEI was correlated with agricultural land in the riparian zone, highlighting the importance of vegetated riparian buffers in providing fish habitat. Establishing a strong correlation with fish metrics remains challenging. Nevertheless, a modified MQI targeting ecological health could be used as an effective management tool for aquatic conservation. [ABSTRACT FROM AUTHOR]

The geomorphology of the Zanjanroud basin is affected by the active tectonic zones resulting from the interaction of the Soltanieh, Zanjan, Tarem, and Manjil faults and the faults that have been investigated more closely in this research. The interaction of these faults has made this basin in the form of a small high plateau, heterogeneous compared to the surrounding areas and a suitable place for the establishment of human settlements. In this research, remote sensing and geomorphometric techniques have been used to identify the lineaments and tectonic evidence in order to discover the tectonic effect on the geomorphology of the basin. The contour lines have been converted into a map after checking with the help of telemetry, geomorphometry and field techniques. Then, by analyzing and interpreting the evidence, the relationship between the dynamic pattern of the faults and its effects on the morphology of different landforms is presented with an emphasis on the interactive reconstruction of drainage networks and faults. The results show that the active tectonics of the faults are concentrated towards the centre of the basin and Zanjanroud area. On the other hand, the compliance of the morphology and topographical trends of the basin, as well as the Zanjan River canal and many drainages with the extraction lines with the help of geomorphometric techniques, clearly shows the effectiveness of geomorphometry to evaluate and prove the impact of terraforming on the geomorphology of the basins. Although no destructive earthquake has been reported in the region, But the presence of morphological evidence and the interruption of Quaternary to Holocene deposits indicate the active deformation of the region. Therefore, it seems that the fault systems of the basin have the potential to create earthquakes with a much higher magnitude than what has happened so far, which indicates the necessity of planning based on a detailed study of the faults in the region. [ABSTRACT FROM AUTHOR]

Hydrogeomorphic characteristics of the Sita-Swarna river basin, Western Ghats, India, are investigated to understand the influence of lithology, structure and geological control on the channel morphology. For preliminary investigation, remote sensing, geomorphic and morphometric analysis was carried out, producing slope, aspect and lineament maps from a 30 m resolution Digital Elevation Model (DEM) with the help of GIS. Remote sensing analysis inferred a steep south-to-southwest slope with dominant lineaments trending NW and ENE to E in the middle reaches of the Sita-Swarna river basin. These lineaments are deduced to have possibly been instigated by faults, shear zones, dyke ridges, or subsurface structures that influence the surficial topography. Upland and pediment geomorphic zone were identified, inferring Western Ghats Escarpment (WGE) and gently coastward W-sloping dissected pediment surface. A comprehensive morphometric analysis is performed using various linear, areal, and relief parameters for basin characterization. The linear parameters infer that the basin is structurally controlled and shows moderate to high permeability and flood susceptible areas downstream. The calculated morphometric parameters for basin characterization reveals that the Sita-Swarna river basin is at the mature stage of development and highly asymmetrical with the westward tilt, which indicates a possible influence of paleo tectonism. Rapid runoff is observed due to the steep escarpment leading to less infiltration and flash flood possibility during heavy rainfall. The present study mainly establishes the potential application of remote sensing methods to quantify the hydrogeological aspects, basin morphometry and landscape evaluation in the tropical climatic zone.

Aim: Freshwater invasions are a global conservation issue. Emerging tools for biogeographical analyses can provide critical information for their effective management and monitoring. Here, we propose a method to assess the distribution of environmental resistance of stream ecosystems to biological invasions by coupling multi‐stage habitat potential models for non‐native species. Location: Andean Patagonia (Chile and Argentina). Taxa: North American beaver (Castor canadensis), Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch). Methods: Environmental resistance to invasive species was mapped throughout a large region of Patagonia by stacking multi‐stage habitat relationships for each target species and assessing the complementation between critical habitats at multiple scales. We generated an environmental model of stream networks derived from high‐resolution topographic and climatic data representing 15,406 drainage basins (>1 km2) covering an area of 369,791 km2. We quantified the intrinsic potential of stream‐reaches (100‐m and 1000‐m) to sustain high‐quality habitats and assessed habitat complementation (i.e., abundance and proximity) at the sub‐basin scale as a proxy for environmental resistance. Results: Our model revealed high heterogeneity in the distribution of environmental resistance to invasions throughout the study region, providing case‐specific insights for the research and management of invaders. Main Conclusions: Environmental resistance modelling is a novel method to study the biogeography of riverine invasions. Our approach is compatible with additional sources of information about species and the environment and shows versatility to diverse invasion scenarios and data sources. This method can be useful in prioritising research and management of incipient and spreading invasions, especially for large and data‐poor regions. [ABSTRACT FROM AUTHOR]

The geomorphology of the Zanjanroud basin is affected by the active tectonic zones resulting from the interaction of the Soltanieh, Zanjan, Tarem, and Manjil faults and the faults that have been investigated more closely in this research. The interaction of these faults has made this basin in the form of a small high plateau, heterogeneous compared to the surrounding areas and a suitable place for the establishment of human settlements. In this research, remote sensing and geomorphometric techniques have been used to identify the lineaments and tectonic evidence in order to discover the tectonic effect on the geomorphology of the basin. The contour lines have been converted into a map after checking with the help of telemetry, geomorphometry and field techniques. Then, by analyzing and interpreting the evidence, the relationship between the dynamic pattern of the faults and its effects on the morphology of different landforms is presented with an emphasis on the interactive reconstruction of drainage networks and faults. The results show that the active tectonics of the faults are concentrated towards the centre of the basin and Zanjanroud area. On the other hand, the compliance of the morphology and topographical trends of the basin, as well as the Zanjan River canal and many drainages with the extraction lines with the help of geomorphometric techniques, clearly shows the effectiveness of geomorphometry to evaluate and prove the impact of terraforming on the geomorphology of the basins. Although no destructive earthquake has been reported in the region, But the presence of morphological evidence and the interruption of Quaternary to Holocene deposits indicate the active deformation of the region. Therefore, it seems that the fault systems of the basin have the potential to create earthquakes with a much higher magnitude than what has happened so far, which indicates the necessity of planning based on a detailed study of the faults in the region. [ABSTRACT FROM AUTHOR]

This study predicts sediment yield on various landuse surfaces within the Calabar River Catchment, Nigeria. Five experimental plots of 31 by 23 cm (representing urban, farm, grass, bare, and forest surfaces) were established on a convex slope series with a 20% gradient, oriented along the slope strike. Rainfall, morphological, and hydraulic stations were derived for each plot. Multiple regressions and Factor analysis were employed to analyse the collected data. The research identifies critical factors influencing sediment yield, such as rainfall amount, rainfall intensity, slope gradient, slope length, sand, silt, clay, vegetation cover, and infiltration capacity. The results (p

A dataset of three digital terrain model (DTM) derivatives was produced at 5 m spatial resolution across mainland France. This dataset includes (i) a topographic wetness index (TWI) that characterizes potential soil wetness as a function of the contributing area and local slope, (ii) a multi-scale topographic position color composite (MTPCC) that describes the position of a pixel relative to its neighborhood at three spatial scales, and (iii) a vertical distance to channel network index (VDCNI) that expresses the vertical height between the elevation of a pixel and the nearest channel. These three raster layers were derived from the French national airborne DTM at 5 m spatial resolution and the vector layer of the channel network of the national hydrological database. This unprecedented fine-scale dataset opens new insights for geomorphological analysis. It can be used for several purposes, such as environmental modeling, risk assessment, or water-resource management.

The Ganga River is one of the largest river systems in the world that has built extensive alluvial plains in northern India. The stretch of the Lower Ganga River is vulnerable to siltation because of: (a) the naturally low slope in the alluvial stretch; (b) the confluence of several highly sediment‐charged rivers such as the Ghaghra, Gandak, and Kosi; and (c) the reduction in non‐monsoon flows because of upstream abstractions of both surface and groundwater. Additionally, the Farakka barrage has impacted the morphology of the Ganga River significantly, both upstream and downstream of the barrage. Large‐scale siltation in several reaches has reduced the channel capacity, leading to catastrophic floods in this region even at low discharges. This work has utilized historical remote sensing data and UAV surveys to reconstruct channel morphodynamics and compute sediment volumes accumulated in the channel belt along the Lower Ganga River between Buxar and Farakka. The work was carried out by dividing the total length of the river into four continuous stretches: (a) Buxar–Gandhighat (GW1, 160 km); (b) Gandhighat–Hathidah (GW2, 106 km); (c) Hathidah–Azmabad (GW3, 182 km); and (d) Azmabad–Farakka (GW4, 132 km). We document that major 'hotspots' of siltation have developed in several reaches of the Lower Ganga during the last four to five decades. Sediment budgeting using planform maps provides estimates of 'extractable' volumes of sediment in GW1, GW2, GW3, and GW4 as 656 ± 48, 706 ± 52, 876 ± 71, and 200 ± 85 Mm3, respectively. These estimates are considerably lower than those computed from the hydrological approach using observed suspended sediment load data, which assumes uniform sedimentation between two stations. Further, our approach provides reach‐scale hotspots of aggradation and estimates of extractable sediment volumes, and this can be very useful for river managers to develop a strategic sediment management plan for the given stretch of the Ganga River. [ABSTRACT FROM AUTHOR]

Geohazards are often portrayed as a calamity that has a detrimental effect on humans and the environment. It is usually uncommon to consider geohazards in the opposite context. Therefore, this study examines the positive effects of an earthquake event centered in Ranau, Sabah, especially from the aspect of ecotourism development. A total of 27 homestay entrepreneurs in Kampung Melangkap were interviewed in this study. The raw data collected during the interview were conceptually and descriptively analyzed using the ATLAS.ti 8 software. Observation techniques were used to supplement the interviews. This study found that the morphological changes of the Panataran Kedamaian River in Kampung Melangkap were a result of an earthquake centered in Ranau. This disaster has led to the development of more interesting physical attractions, attracting many tourists to Melangkap Village. The dramatic increase of tourists in Melangkap during the post-geohazard phase has become the starting point for the economic growth of ecotourism in the region. This is shown by the increase in the number of homestay entrepreneurs, the expansion in the size of their businesses, higher overall income of homestay entrepreneurs, and better job opportunities for the local population. [ABSTRACT FROM AUTHOR]

ABSTRAK Mata air merupakan sumber air bersih potensial yang dimanfaatkan masyarakat di Lembah Banjarasri Kecamatan Kalibawang Kabupaten Kulonprogo. Tujuan penelitian ini adalah menganalisis karakteristik hidrogeomorfologi mata air di daerah penelitian. Kajian hidrogeomorfologi menjelaskan tentang aspek-aspek geomorfologi yang berpengaruh terhadap karakteristik pemunculan mata air pada setiap satuan bentuk lahan. Hasil penelitian menunjukkan bahwa secara geomorfologi di Lembah Banjarasri terdapat 2 mata air yang muncul pada bentuk lahan lerengkaki perbukitan struktural terdenudasi kuat, dengan debit aliran kecil, karena dipengaruhi oleh kemiringan lereng yang sangat curam, tipisnya lapisan tanah sebagai media infiltrasi air hujan, dan jenis material penyusun berupa batuan andesit tua yang relatif kedap air. Terdapat 12 mata air pada bentuk lahan lerengkaki perbukitan struktural terdenudasi sedang tersusun oleh batugamping Formasi Sentolo, berstruktur percelahan dan retakan, sehingga permeabilitas dan prorositas batuan tinggi dan berpotensi memunculkan mata air. Hanya terdapat 4 mata air yang muncul pada lerengkaki perbukitan struktural terdenudasi ringan, karena faktor material penyusun berupa batuan beku andesit tua Formasi Kebobutak. Pada bentuk lahan dataran aluvial terdapat 3 mata air, karena faktor topografi yang relatif datar hingga landai, dan tebalnya endapan aluvium, serta tidak ada kontrol struktur yang tegas sebagai faktor pemunculan mata air. Kata kunci: bentuk lahan, hidrogeomorfologi, mata air ABSTRACT Spring is the potential sources of clean water that is used by the community in the Banjarasri Valley, Kalibawang District, Kulonprogo Regency. The aim of this study was to analyze the spring hydrogeomorphological characteristics in the study area. The hydrogeomorphology study explains the geomorphological aspects that affect the characteristics of the appearance of springs in each existing landform unit. Results of the research show that in the Banjarasri valley there are 2 springs that appear on the slopes of the foothills, structurally strongly denuded, with small flow rates, because they are influenced by very steep slopes, the thin layer of soil as a medium for rainwater infiltration, and the type of constituent material in the form of old andesite rocks which are relatively massive and impermeable to water. There are 12 springs that appear on the slopes of the foothills, a moderately denuded structural structure composed of the Sentolo Formation limestones, which has many crevices and fractures structures, so that the permeability and porosity of the rock are high and have the potential to generate springs. There are only 4 springs that appear on the slopes of the foothills with a light denuded structure, due to the constituent material in the form of old andesite igneous rocks originating from the Kebobutak Formation. In alluvial plain landforms, there are 3 springs, due to the relatively flat to sloping topography, thick alluvium and colluvium deposits on the slopes, and there is no firm structural control as a strong factor causing the emergence of springs. Keywords: landform, hydrogeomorphology, spring

Abstract Stream fishes are restricted to specific environments with appropriate habitats for feeding and reproduction. Interactions between streams and surrounding landscapes influence the availability and type of fish habitat, nutrient concentrations, suspended solids, and substrate composition. Valley width and gradient are geomorphological variables that influence the frequency and intensity that a stream interacts with the surrounding landscape. For example, in constrained valleys, canyon walls are steeply sloped and valleys are narrow, limiting the movement of water into riparian zones. Wide valleys have long, flat floodplains that are inundated with high discharge. We tested for differences in fish assemblages with geomorphology variation among stream sites. We selected rivers in similar forested and endorheic ecoregion types of the United States and Mongolia. Sites where we collected were defined as geomorphologically unique river segments (i.e., functional process zones; FPZs) using an automated ArcGIS‐based tool. This tool extracts geomorphic variables at the valley and catchment scales and uses them to cluster stream segments based on their similarity. We collected a representative fish sample from replicates of FPZs. Then, we used constrained ordinations to determine whether river geomorphology could predict fish assemblage variation. Our constrained ordination approach using geomorphology to predict fish assemblages resulted in significance using fish taxonomy and traits in several watersheds. The watersheds where constrained ordinations were not successful were next analyzed with unconstrained ordinations to examine patterns among fish taxonomy and traits with geomorphology variables. Common geomorphology variables as predictors for taxonomic fish assemblages were river gradient, valley width, and valley slope. Significant geomorphology predictors of functional traits were valley width‐to‐floor width ratio, elevation, gradient, and channel sinuosity. These results provide evidence that fish assemblages respond similarly and strongly to geomorphic variables on two continents.

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Keywords: Hydrogeomorphology; Biogeochemistry; Climatic variability; Environmental change; Ecosystem services EN Hydrogeomorphology Biogeochemistry Climatic variability Environmental change Ecosystem services 607 622 16 08/22/22 20220801 NES 220801 Introduction The United Nations Environment Programme (UNEP [64]) classifies global drylands according to an Aridity Index (AI), defined as the ratio between mean annual precipitation (MAP) and potential evapotranspiration (PET). Further, process dynamics in WiDs are equally as vulnerable as humid region wetlands to human-induced changes in riverine sediment flux, that may cause either siltation (e.g., Wolanski et al. [72], Gell et al. [9]) or erosion (Fryirs and Brierley [7]) of wetlands downstream. Emergent theme 2: implications of climate change for biodiversity in wetlands in drylands WiDs have been shown to have extremely high faunal diversity that may exceed that of more permanent wetlands. In valley-bottom wetland systems, organic accretion rates in permanent, humid-region wetlands typically outstripped clastic sedimentation rates of seasonal wetlands. [Extracted from the article]

This study aims to identify the potential groundwater in Jedong, Malang, East Java. The hydrogeomorphological approach is a suitable approach to describe the relationship between hydrological and geomorphological processes on and below the earth's surface. The survey of geoelectricity complements the hydrogeomorphological approach. It will give a better description of the groundwater conditions below the earth's surface. Based on the research, there are 2 hydrogeomorphological units in the study area, which are: Volcanic Foot Valley Unit and Volcanic Foot Ridge Unit. The best groundwater potential is in Volcanic Foot Valley Hydrogeomorphological unit, namely Awar-awar Valley and Cokro Valley. The valleys are dominated by gully erosion and landslides. They have surface deposits up to a depth of 7 meters, and lots of outcrops of breccia, pumice, and andesite boulders. The valley’s springs discharge between 56 - 198 m3/day. The average infiltration rate in the valley is 1776 mm / hour, with sandy soil material. The best aquifer consisting of sandy material is more than 10 meters in depth, based on the geoelectrical survey. Water in the aquiclude layer, cannot be exploited because it is breccia and tuff material. The Sawah valley cannot be exploited further because the groundwater potential is very low. This can be identified by the thick water outflow seepage. In the Volcanic Foot Ridge Hydrogeomorphological unit, the groundwater potential is also very small. Hydrogeomorphically, water will flow down the slope to the valley. It will reduce the infiltration rate. In general, the ridge area is only used for settlement, while the slopes are used for dryland agriculture. The geoelectric analysis results show that the groundwater potential is at a depth of more than 45 meters. This research’s results show that the combination of the hydrogeomorphological approach and the geoelectric use will provide a better description of the potential groundwater.

Hydrogeomorphic factors were suspected to contribute to the persistent gully erosion taking place in Nanka, Ogwashi and Benin formations underlying the southern Anambra State, Nigeria. Therefore, this study investigated the impact of hydrology and geomorphology on gully development and expansion in this area using integrated field survey, hydrological, geotechnical and geomorphological approaches. Field survey and hydrological results revealed that the study area is characterized by numerous surface water bodies and shallow groundwater systems. Both the surface waters and groundwater have a westward flow direction, from areas of high elevations on the Nanka Formation to areas of low elevations on the Ogwashi and Benin formations. Geotechnical results revealed that the soils are permeable, weak, easily dispersible and collapsible. Geomorphological analysis showed that the area is characterized by uneven badland topography, high gully slope gradients, concave slopes, poor land-use practices, and low vegetation cover. Generally, the results of this study indicated that hydrogeomorphology and soil engineering properties substantially influence the gullying processes in the area. However, areas underlain by the Nanka Formation have higher gullying intensity than in areas underlain by the Ogwashi and Benin formations due to variations in their hydrogeomorphological characteristics.

[Display omitted] • Hydrogeomorphological method for flood analyses in narrow rivers. • Integration of geomorphological knowledge and hydrologic-hydraulic modelling. • Study of flood events and hazards associated with probabilities of occurrence. • Analyses at high spatiotemporal resolutions at local scale. • Predictions of flood extents at different flows to define management strategies. Fluvial flood risk management requires precise knowledge of flooding processes; thus, there is a need to carry out a detailed hydrological, hydraulic, and geomorphologic analysis to understand floods and the factors that influence them. Although the integration of geomorphological methods and hydrological-hydraulic modelling is known to be crucial for flood risk analysis, it remains a challenge to apply these approaches to the understanding of floods in small and medium-sized catchments, focusing on complex fluvial systems that have been highly modified. In this work, a hydrogeomorphological methodology was developed to analyse fluvial floods in narrow rivers with broad complex alluvial plains. The procedure comprises different phases that combine hydrologic-hydraulic modelling and a geomorphological break-down. Critically, this allows for a detailed analysis of existing relationships among erosional and depositional fluvial landforms and hydraulic parameters, comprising geometric sections, discharges, depths, flood extents and, therefore, flood hazards. The approach involves the analysis of specific flood events beforehand and the study of fluvial floods associated with different probabilities of occurrence afterwards. The information employed in the present study incorporates high- detailed inputs comprising hourly time series of hydrometeorological data, LiDAR data to extract high-precision terrain information, fluvial geomorphic maps and flood event extents based on Sentinel-2 imagery. We demonstrate this methodology in the Carrión River, located in the province of Palencia, Spain, whose characteristics include a wide complex alluvial plain, reaches highly modified by anthropic interventions and recurrent flood episodes. This hydrogeomorphological approach allowed the integration of geomorphological knowledge and hydrologic-hydraulic modelling in flood analysis. As a result, it led to a deeper comprehension of the processes of inundation, which would be challenging to thoroughly understand without incorporating a holistic method, an essential factor for defining effective flood management strategies. [ABSTRACT FROM AUTHOR]

Debris floods most commonly occur in steep mountain channels and on their alluvial fans but can also occur on small gravel bed rivers with watershed areas up to several hundred square kilometers. This became obvious during July 2021 and November 2021 debris floods in northwestern Germany and southwestern British Columbia, Canada. We subdivide debris floods into three categories: those triggered by a supra‐critical bed shear stress ratio, form by dilution from debris flows, and resulting from outbreak floods. This trichotomy challenges traditional hazard assessments; debris floods classify as a fluvial process, yet their destructive mechanics are difficult to characterize. Key hazards interact spatially and temporally in debris floods: inundation, scour, sediment transport and deposition and bank erosion. We describe approaches to quantify hazards by systematically accounting for these processes and introduce a novel approach for hazard quantification and mapping in which flow velocity, depth, and presumed fluid density are combined with the annual event frequency for all event scenarios. The derivative "composite hazard maps" are equally valid for debris floods and debris flows. Isolines of bank erosion based on a probabilistic analysis of a physically based model are added to capture the potential of debris floods to abruptly widen their channels. Substantial challenges remain, specifically in the reliable prediction of sediment transport and progressive bank erosion. Our intention is to homogenize debris‐flood hazard assessments and especially mapping methodologies. This could allow for systematic integration with landuse policies assuring consistency among approaches executed by practitioners acting in this field. Plain Language Summary: Debris floods can be highly destructive. We provide a comprehensive methodology to assess debris‐flood hazards with the goal of developing a consistent approach, allowing for better input to quantitative risk assessments and the selection of appropriate mitigation measures. We suggest a method for debris‐flood mapping that combines the recurrence interval of various debris flood scenarios with their impact force and bank erosion to support a multi‐faceted hazard assessment. Key Points: Debris flood assessments are under‐researched and poorly constrained. This contribution attempts to rectify that situationBeyond debris flood inundation, this contribution outlines methods for sediment bulking, sediment transport, and bank erosionA new method for hazard mapping is proposed based on impact force and event frequency. This allows direct comparison of study sites [ABSTRACT FROM AUTHOR]

Hydrogeomorphology is an emerging discipline that studies the relationship between landforms and hydrology, focusing on groundwater and surface water interactions. This study presents the methodology for the elaboration of a hydro-geomorphological map oriented to illustrate the relationships between the aquifer components and geomorphological characteristics in the United States-Mexico Transboundary San Pedro Aquifer (TSPA). This information contributes to a further understanding of the TSPA, facilitates the location of groundwater recharge and discharge zones, is useful for the development of sustainable groundwater management strategies, and could be useful in developing conceptual and numerical groundwater models for the region. [ABSTRACT FROM AUTHOR]

Over the past decades, riparian land-use changes coupled to the multiplication of river infrastructures have enhanced vulnerability issues for societies and ecosystems located along large rivers. Exposure to geohazards is also changing due to the ongoing climate change, underlining the need for flexible management strategies for riparian environments. In this perspective, GIS-based mapping allows integrating a wide range of environmental data. However, such datasets are often incomplete and not homogeneous over large geographical scales, which can be problematic for the implementation of regional land-use planning strategies. Using the St. Lawrence fluvial system (SLFS) (Québec, Canada) as a case study, this article reports and describes a high-resolution approach to map position, characteristics and erosion susceptibility of natural and artificial riverbanks from a combination of field-based, remote sensing and local knowledge-derived data. This approach allowed identifying erosion-prone sites and highlighting dominant erosion processes and spatially constrain them along the SLFS. The proposed geospatial framework constitutes (1) an initial portrait of the riverscape that will allow an effective implementation of future monitoring and process-based studies; and (2) a first step in supporting land-use planning stakeholders in the selection of appropriate measures to ensure a greater resilience of riparian communities and ecosystems.

Water and sediment transport and redistribution around drainage ways are major riparian zone processes that affect soil chemistry and water quality of watersheds. This is more so for urbanized watersheds that generate more runoff and sediments which end up in the drainage ways. This study was done to evaluate the pedogeomorphic variability of the Aldridge Creek Watershed in Alabama, and to assess its impact on the water quality and soil properties of the watershed. Sampling locations along the creek were subdivided into five stream sites and geo-referenced. Soil samples from the riparian buffers and water samples from the creek were collected from upstream, midstream, and downstream sites of the watershed and analyzed for trace metal concentration and distribution. The trace metal concentration in soils of the riparian buffers varied from 20 to 34 µg g−1 for lead (Pb), 50–85 µg g−1 for zinc (Zn), 6–17 µg g−1 for copper (Cu), 11–18 µg g−1 for nickel (Ni) and 5–21 µg g−1 for arsenic (As). At all sites, Pb, Zn, Ni, Cu and As concentrations in the riparian zone locations were 7–67% higher than the upper slopes indicating that the riparian zone is a potential source or sink of trace metals along the flow pathways between the upper slope soils and the stream. While there were significant differences in the distribution of trace metals in soils between the upslope and riparian zone locations at the upstream, midstream, and downstream sites, there was no significant difference in the stream water trace metals concentration between the sites of the watershed.

Riparian ecosystems occur at the interface between aquatic and terrestrial ecosystems, and have important environmental functions. As they are highly dynamic areas with great spatial variability, they are difficult to be identified and delimited. The present study deals with the possibility of using plinthite occurrences at the base of slopes in contact with the floodplains as indicators of the riparian extension in the Apuaê-Mirim/RS river basin. From the analyzes made, it was observed that the variation of the subsurface humidity responsible for the formation of the plinthite in the selected points results from the influence of the geometric shapes in the bases of the slopes, the typologies of uses and land coverings, and the textural characteristics of the soils along the profiles. [ABSTRACT FROM AUTHOR]

Pastures occupy a large part of Brazilian national territory, being of heterogeneous characteristics and varying in climate, fertility, and management. Water erosion, generated by the action of rainfall, is a principal source of soil depletion. These soils exhibit distinct behaviors spatially and temporally. Therefore, this research aims to evaluate the water and soil losses in a pasture of the Cerrado region during two periods of the year (winter and summer) with the aim of understanding the hydro-geomorphological dynamic of the pastures in question. A rainfall simulator was calibrated at 64.34 mm/h, to replicate similar intensities to those of the study region, for 30 minutes (32.17 mm) over four erosion plots. Overall, the plots presented low water and sediment losses, with the largest runoff volumes in the summer and the highest erosion rates in winter. These results are connected to seasonal climate variations expressed in the region, which are reflected in the plant growth habits, generating alterations in the structural quality of the pastures. It follows that the return of the rainy season (winter-summer transition) represents a critical phase for the triggering of the erosive process. [ABSTRACT FROM AUTHOR]

Stream fishes are restricted to specific environments with appropriate habitats for feeding and reproduction. Interactions between streams and surrounding landscapes influence the availability and type of fish habitat, nutrient concentrations, suspended solids, and substrate composition. Valley width and gradient are geomorphological variables that influence the frequency and intensity that a stream interacts with the surrounding landscape. For example, in constrained valleys, canyon walls are steeply sloped and valleys are narrow, limiting the movement of water into riparian zones. Wide valleys have long, flat floodplains that are inundated with high discharge. We tested for differences in fish assemblages with geomorphology variation among stream sites. We selected rivers in similar forested and endorheic ecoregion types of the United States and Mongolia. Sites where we collected were defined as geomorphologically unique river segments (i.e., functional process zones; FPZs) using an automated ArcGIS‐based tool. This tool extracts geomorphic variables at the valley and catchment scales and uses them to cluster stream segments based on their similarity. We collected a representative fish sample from replicates of FPZs. Then, we used constrained ordinations to determine whether river geomorphology could predict fish assemblage variation. Our constrained ordination approach using geomorphology to predict fish assemblages resulted in significance using fish taxonomy and traits in several watersheds. The watersheds where constrained ordinations were not successful were next analyzed with unconstrained ordinations to examine patterns among fish taxonomy and traits with geomorphology variables. Common geomorphology variables as predictors for taxonomic fish assemblages were river gradient, valley width, and valley slope. Significant geomorphology predictors of functional traits were valley width‐to‐floor width ratio, elevation, gradient, and channel sinuosity. These results provide evidence that fish assemblages respond similarly and strongly to geomorphic variables on two continents. [ABSTRACT FROM AUTHOR]

Changes in environmental variables induced by ecological succession and hydrogeomorphological processes affects riparian vegetation dynamics along rivers. The biotic and abiotic factors driving local patch dynamics of riparian species is little known for early successional stages.To fill this gap, we examined local patch dynamics and frequency of occurrence of a protected riparian pioneer species (Typha minima Hoppe) and related it to several biotic and abiotic variables along the Isère River (France) from 2016 to 2019.We monitored biotic and abiotic factors related to ecological succession and sediment accretion. We implemented Linear Mixed and Generalized Mixed Models to analyze how environmental factors affected patch boundary dynamics of T. minima. Finally, we built a Structural Equation Model to describe potential relationships between T. minima frequency, height above mean water level, vegetation cover and composition.We found that a thick layer of silt and sand deposits as well as a moderate herbaceous and low shrub cover layer characterized T. minima patch progression close to the mean water level. Typha minima stands did not seem to expand on coarser substrates with lower herbaceous cover. Its maintenance was associated with large silt and sand deposits and high cover of herbaceous plants and shrubs well above the mean water level. The variables characterizing patch regression were not clearly identified. Finally, the interaction between bar height, vegetation cover and succession stage did not explain variations in T. minima frequency.Our results provide knowledge about the environmental variables associated with T. minima patch dynamics, which are useful for future conservation and restoration projects. Habitat rejuvenation through restoration of natural river flow regimes could sustain local T. minima transplantation and large population turnover essential to the conservation of this species. [ABSTRACT FROM AUTHOR]

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In recent years, a renewed interest in large-scale hydraulic interventions has developed, frequently justified by the premise of making the agricultural and energy sectors climate-resilient. Despite this important climate effort, hydraulic interventions are controversial and have far-reaching impacts on river-dependent communities and the environment. Drawing on gis analyses of remote sensing images and qualitative and quantitative empirical evidence from the field, this PhD dissertation focused on the impact of two large dams and one inter-basin water transfer (ibwt) on downstream socio-hydrologic systems (coupled human-water systems) in Ethiopia. The results indicated that (i) downstream hydrogeomorphic systems drastically altered after the implementation of the hydraulic interventions, (ii) small-scale farmer-led irrigation systems more efficiently increased crop productivities than several largescale irrigation projects, (iii) the newly induced hydrologic regimes strongly altered downstream social interactions due to impeded river crossing and (iv) ill-prepared land redistributions and resettlements left thousands of households with a high risk of impoverishment. [ABSTRACT FROM AUTHOR]

A geo‐eco‐hydrological approach is developed and applied to assess river condition for three anabranching reaches in the Source Zone of the Yellow River. Building on principles of the River Styles Framework, attributes used to assess river condition are tailored to measure key attributes of the character and behavior for the type of river under consideration. Hydrogeomorphic process linkages with riparian vegetation function are appraised using the Fluvial Biogeomorphic Succession Model for each reach. Reference conditions incorporate measures of river geo‐eco‐hydrological structural integrity and functional connectivity, relating the expected "best achievable" conditions to prevailing land use practices in these grazing adapted grassland ecosystems. Contemporary conditions closely approximate expected reference conditions in hydro‐geomorphic terms. While vegetation interactions function effectively in the active channel zone, they are subject to land use pressures in many floodplain areas. Minimizing impacts of direct anthropogenic disturbance, while promoting passive management practices that support self‐sustaining processes, are considered to offer the best prospect to maintain good river condition in these reaches. Major commitment to environmental protection in this area makes this a realistic possibility. The generic approach to analysis of geo‐eco‐hydrological condition is readily transferable to other situations. [ABSTRACT FROM AUTHOR]

• Either climate data or streamflow data alone is not sufficient to accurately estimate SSL. • Gradient boosting models accurately predict SSL using hydro-climate data. • Hydrological metrics improve the accuracy SSL modeling during model calibration. • The prediction uncertainty of SSL increases with the basin's area. • Average ensemble modeling enhanced the accuracy of models in rivers. Machine learning (ML) models have the potential to improve the accuracy of Suspended Sediment Load (SSL) predictions. However, their ability to incorporate climate data to enhance SSL predictions remains underexplored. This study investigates the efficacy of ML models in modeling sediment transport using hydro-climate variables as input data. Boosted decision tree models, including Xgboost, LightGBM, and Catboost, were employed to estimate SSL using hydro-climate variables such as streamflow and precipitation, as well as maximum and minimum temperatures. The models were trained, optimized, and evaluated using either climate/streamflow data or a combination of both, encompassing 47 gauges across the contiguous United States (CONUS) between 1950 and 2022. The results demonstrate that streamflow data alone is insufficient for accurate SSL estimation in all rivers. Consequently, integrating climate data and streamflow data proved effective in predicting SSL at the daily scale across diverse climate zones with commendable accuracy. The models achieved an average Nash-Sutcliffe Efficiency (NSE) of > 0.66, Kling-Gupta Efficiency (KGE) of > 0.67, and Willmott Index (WI) of > 0.83 during the unseen (test) phase. These findings highlight the potential of ML models, particularly when combining climate data with streamflow, to enhance SSL predictions and improve our understanding of sediment transport dynamics. [ABSTRACT FROM AUTHOR]

Flooding is one of the major environmental hazards within the last century that widespread around the globe. Flooding is often thought of as a result of heavy rainfall, but different geomorphic and hydrologic systems have a different response to the precipitation. The main goal of the research is studying of flooding in the Maroon Catchment that severe flooding has been inflicted great losses in the agricultural, residential and deaths sectors over the past years. Usually, after any heavy rainfall, flooding will be expected. Maroon Catchment has located in the in the Kohgiluyeh and Boyer-Ahmad province, between 30° 40´ to 31° 20´ of northern latitudes and 50° 5´ to 51°10´ of eastern longitudes. To evaluate the various effective hydro geomorphologic parameters on flooding in the basin, we specified 18 different variable, but according to cluster analysis and multivariable regression models, effective parameters on the flood in the region were summarized in 6 factors includes: area, perimeter, and width of the equivalent rectangular, the total length of the drainage network, the length of the basin and average flow length. After choosing variable, standardization of them and using different methods, sub-catchment were separated. According to, sub-catchment divide to four homogeneous groups, each group contain some sub-catchment as follows: group 1 includes 1, 2, 3, 4, 7, 8, 9, 17, 10, 20sub-catchments; group 2 includes 5, 6, 11, 14, 16 sub-catchments, group 3 includes 12, 13, 15, 19sub-catchments, and group 4 include 18sub-catchment. On the basis of the parameters and also analysis of them, we were observed that the sub-catchment of the 1 group had severe floods, the 2 group with medium floods, the 3 group with low floods and the 4 group with the intensity of floods.