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Space use by small mammals should mirror their immediate needs for food and predator shelters but can also be influenced by seasonal changes in biotic and abiotic factors. Lemmings are keystone species of the tundra food web, but information on their spatial distribution in relation to habitat heterogeneity is still scant, especially at a fine scale. In this study, we used spatially explicit capture–recapture methods to determine how topography, hydrology, vegetation, and soil characteristics influence the fine-scale spatial variations in summer density of brown lemmings (Lemmus trimucronatus). Lemmings were monitored throughout the summer in wet and mesic tundra habitats and in a predator exclusion grid, which was also located in mesic tundra. We found that in wet tundra, lemming densities were higher at sites with a rugged topography dominated by hummocks, but only during snow melt. In both mesic tundra sites, lemming densities were higher in sites with poor drainage and low aspect throughout the summer. We found no clear association between lemming densities and any tested vegetation or soil variables. Overall, hydrology and topography appear to play a dominant role in small-scale space use of brown lemmings with a secondary role for predator avoidance and food plant abundance. [ABSTRACT FROM AUTHOR]

Depuis le milieu du vingtième siècle, les paysages bocagers du nord-ouest de la France subissent d’importantes mutations. Sous l’effet de la transformation foncière des exploitations agricoles, les parcellaires sont rationnalisés, remembrés et les haies sont fréquemment arasées. Ces mutations ont pour répercussion de multiplier les transferts hydro-sédimentaires et les connectivités hydrologiques entre les parcelles agricoles et le cours d’eau, impactant l’environnement (érosion des sols, pertes en sol, la pollution des milieux aquatiques). Ces conséquences déjà pressantes et pesantes pourraient devenir récurrentes dans un contexte de changement climatique. À l’heure où les enjeux liés à l’aménagement et à la préservation des territoires bocagers sont à repenser, il est intéressant de s’interroger sur la « vertueusité » des paysages passés au-regard des transferts hydro-sédimentaires. Cet article étudie l’évolution des connectivités hydrologiques depuis deux siècles sur différents bassins versants bocagers, afin d’offrir des perspectives quant à la gestion durable et future des territoires.

Copyright of Journal of Social Sciences & Humanities Researches is the property of Mugla Sitki Kocman University, Institute of Social Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Österreichische Wasser- und Abfallwirtschaft is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study is a meta-analysis of global articles on hydrological nutrient dynamics to determine trends and consensus on: (1) the effects of climate change-induced hydrological and temperature drivers on nutrient dynamics and how these effects vary along the catchment continuum from land to river to lake; (2) the convergence of climate change impacts with other anthropogenic pressures (agriculture, urbanization) in nutrient dynamics; and (3) regional variability in the effects of climate change on nutrient dynamics and water-quality impairment across different climate zones. An innovative web crawler tool was employed to help critically synthesize the information in the literature. The literature suggests that climate change will impact nutrient dynamics around the globe and exacerbate contemporary water-quality challenges. Nutrient leaching and overland flow transport are projected to increase globally, promoted by extreme precipitation. Seasonal variations in streamflow are expected to emulate changing precipitation patterns, but the specific local impacts of climate change on hydrology and nutrient dynamics will vary both seasonally and regionally. Plant activity may reduce some of this load in nonagricultural soils if the expected increase in plant uptake of nutrients prompted by increased temperatures can compensate for greater nitrogen (N) and phosphorus (P) mineralization, N deposition, and leaching rates. High-temperature forest and grass fires may help reduce mineralization and microbial turnover by altering N speciation via the pyrolysis of organic matter. In agricultural areas that are at higher risk of erosion, extreme precipitation will exacerbate existing water-quality issues, and greater plant nutrient uptake may lead to an increase in fertilizer use. Future urban expansion will amplify these effects. Higher ambient temperatures will promote harmful cyanobacterial blooms by enhancing thermal stratification, increasing nutrient load into streams and lakes from extreme precipitation events, decreasing summer flow and thus baseflow dilution capacity, and increasing water and nutrient residence times during increasingly frequent droughts. Land management decisions must consider the nuanced regional and seasonal changes identified in this review (realized and predicted). Such knowledge is critical to increasing international cooperation and accelerating action toward the United Nations's global sustainability goals and the specific objectives of the Conference of Parties (COP) 26. [ABSTRACT FROM AUTHOR]

Copyright of LHB: Hydroscience Journal is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Un grand nombre d’opérations de restauration/création de zones humides voient le jour en France. L’efficacité de ces dernières doit être évaluée à court, moyen et long terme. C’est d’ailleurs le cas des opérations de compensation qui sont désormais soumises à obligation de résultat et doivent, pour démontrer l’efficacité de leurs opérations de restauration/création, disposer d’indicateurs robustes et facilement mobilisables. L’indicateur HYDRINDIC a ainsi été construit pour permettre le suivi et l’évaluation de l’efficacité des opérations de restauration/création de zones humides d’un point de vue hydrologique.

More and more projects use single‐shell segmental lining for rock support as well as water and frost protection. Unless the potential water pressure is very high, i.e., above several hundreds of meters, these lining structures are usually built as undrained fully watertight tunnels. The Follo Line Project included a considerable amount of pre‐excavation grouting to reduce the water ingress during construction and invested a lot in injections to close leakage points after the tunnel excavation had finished. This article discusses the various types of injections and reflects critically the use of single‐shell linings for tunnels with high water pressure. [ABSTRACT FROM AUTHOR]

The bidding consortium 3G Gruppe Geotechnik Graz ZT GmbH and Pöyry Infra GmbH as well as Geoconsult ZT GmbH and BGG Consult Dr. Peter Waibel ZT‐GmbH were awarded the contract for the geological and hydrogeological documentation during the construction of the 33 km long Koralm Tunnel, which was split into three lots. To assess the potential for scale deposition, ongoing documentation and surveys of the groundwater inflows were undertaken in addition to the usual hydrogeological documentation. The scope of documentation included mapping of scale deposition and groundwater inflows, regular site visits and sampling of water and solids in the excavated tunnel (shotcrete and segmental lining) both during and after excavation works. Furthermore, long‐term monitoring of the water inflows (on‐site parameters, determination of / changes in humidity) and laboratory analysis of the individual and mixed groundwater samples identified the parameters required to assess the potential for scale deposition. The documentation, analysis and assessments provided the basis for ultimately deciding which tunnel sections would require hardness stabilisation measures to reduce or inhibit scaling and calcium carbonate precipitations in the drainage system during the operational phase. [ABSTRACT FROM AUTHOR]

Scale formation in water drainage systems occurs in diverse forms. In tunnel drainage systems in particular, calcium carbonate deposition can significantly impair water discharge, resulting in costly maintenance work and tunnel closures. This review paper presents and discusses the state of knowledge as well as the current challenges regarding scale formation in tunnel drainage systems in terms of typification, parameters controlling formation, such as hydrochemistry, interfacial phenomena, microbial activity, and countermeasures, such as appropriate adaptation of construction materials, drainage design, inhibitor use and cleaning. Detailed knowledge of the case‐specific scale formation environment and the scaling capacities of the waters provides the basis for the tailored development and evaluation of suitable strategies for successfully reducing maintenance efforts and tunnel closure. For this purpose, time‐ and site‐resolved monitoring of the composition of the solid phases, waters and the tunnel atmosphere during the implementation of the construction project and during the operation of the tunnel is paramount. [ABSTRACT FROM AUTHOR]

A field test was carried out in Koralmtunnel in order to enhance process understanding and to optimize the drainage system in a tunnel section that is complex in terms of hydrochemistry, water inflow and mineral (calcareous scale, iron ochre) and biological (microbial mats) deposits. The field test comprised three test fields with different system components and flow characteristics. The development of critical waters and deposits was recorded by continuous measurements of relevant water and air parameters by means of autonomous sensors/data loggers. Furthermore, the components were "forensically" examined with respect to scale formation. The experiments show the crucial importance of gas exchange (CO2, oxygen ingress), filling level (flow geometry/regime), residence time of waters and water‐air interaction in the drainage system. The type, material consistency, and amount of scale and biofilms depend significantly on specific gradients. Floating scale crusts formed in stagnant sections, biofilms and iron ochre deposits of soft consistency formed at higher flow rates. Seepage packs and siphons turned out to be potential sediment traps with decreasing flow‐through with no access. Drainage hoses and dimpled membranes tend to be beneficial because they can prevent air exchange at relatively high flow rates. High CO2 partial pressure within these components (measured and modeled) inhibits carbonate precipitation. The drainage system is locally designed as a series of direct cross‐drains with simple flow paths, restricted air exchange, precautionary cleaning access, and optional water hardness stabilization (liquid conditioning). [ABSTRACT FROM AUTHOR]

Dilute lakes, herein defined as having an electrical conductivity ≤25 µS cm−1, are considered valuable culturally, as water and recreational resources; biologically, as unique ecosystems; and scientifically, as sentinels of climate change. However, research and interest has been spread over many disciplines focusing on various issues, making hydrologic comparisons somewhat difficult. Here, 15 dilute lakes are subdivided into lake subtypes based on the dominant hydrologic input and output using annual water balance data. Dilute conditions occur in lakes dominated by all hydrologic inputs (precipitation, surface inflow, and groundwater) and outputs (evaporation, surface outflow, and groundwater), though not all possible input/output combinations produce dilute conditions. Of the nine possible hydrologic lake subtypes (three input by three output fluxes), dilute conditions have been reported in six lake subtypes, not just the traditional seepage and drainage lakes typically suggested in the literature. When annual water balance data are plotted on a "Piper‐type" graph, these six hydrologic lake subtypes are grouped into three hydrologic clusters emphasizing specific hydrologic landscape characteristics and limiting conditions hydrology may impose on naturally dilute lakes. Implications of such a classification system and possible future research questions are discussed. [ABSTRACT FROM AUTHOR]

Les stations hydrométriques de Brazzaville et Kinshasa contrôlent 98% du bassin versant du Congo. Elles se situent à la sortie d’un bassin de tranquillisation pour mesurer les hauteurs d’eau et juste en amont d’un déversoir stable et sensible pour contrôler la relation hauteur-débit. Grâce à l’équivalence entre les deux jeux d’échelles, une longue série de référence a été reconstituée à partir de relevés limnimétriques quotidiens depuis 1902. De plus, 154 jaugeages ont été recensés dont 139 au moulinet pour les périodes 1955–1962 et 1971–1981 et 15 autres à l’ADCP depuis 2010. Ils couvrent tout le cycle hydrologique comme les principales phases d’écoulement ainsi que la quasi-totalité du marnage observé depuis 120 ans. Ce travail permet d’une part d’évaluer la stabilité de la section de contrôle grâce aux jaugeages Doppler, initiés 30 ans après la fin de ceux au moulinet et d’autre part, il permet la construction des courbes de tarage hauteur-débit avec estimation de l’incertitude, en combinant la connaissance a priori sur les contrôles hydrauliques et le contenu d’information des jaugeages incertains via la méthode bayésienne BaRatin. Une première estimation de la vitesse du fond mobile du fleuve Congo entre Brazzaville et Kinshasa est présentée.

Les zones tampons humides artificielles installées en région agricole drainée sont efficaces non seulement pour améliorer la qualité chimique de l’eau, mais également pour maintenir la biodiversité locale et la diversité du paysage. Partant de ces constats, les chercheurs d’INRAE ont créé l’outil d’analyse spatiale INSPA (INsertion SPAtiale), qui en croisant les informations sur les fonctions hydrologiques et écologiques d’un territoire permet de sélectionner les sites d’implantation de zones tampons humides artificielles en vue de constituer une mosaïque paysagère favorable à la biodiversité.

Deep tunnels are long tunnel systems which cross different hydrogeological environments as a drainage. Thus, their water inflows have very different characteristics. The tunnel water discharges formed from these water inflows, which drain individual sections of the tunnel system, also have different properties. These discharges from individual tunnel sections – so‐called sectional discharges – are important for determining the geothermal potential of deep tunnels. Knowledge of the origins of sectional discharges and their properties allows optimising the usage of the geothermal potential of the water by provision of adequate tunnel water management. By monitoring sectional discharges, the most effective "mixing scenarios" can be calculated and thus an optimization of the geothermal output can be achieved. The concept of sectional discharges for the geothermal evaluation of deep tunnels is presented based on data from the Brenner Base Tunnel (BBT). [ABSTRACT FROM AUTHOR]

In Southern Germany, geothermal wells target Upper Jurassic carbonates, formerly referred to as Malm, below the Northern Alpine Foreland Basin (NAFB). In the northern, shallower carbonates (3000 m depth), e.g., in the Munich area, hydrothermal systems prevail, and wells yield proper flow rates. Deeper carbonates (< 4000 m) towards the south indicate a petrothermal system due to a decline in porosity and permeability. Inexplicably, fractures only contribute poorly to larger flow rates. This sets the goal for the project Dolomitkluft to analyse the rock mass for options countering low flow rates in two geothermal wells at Geretsried, Bavaria. Therefore, 20 m drill cores from 4600 to 4715 m total vertical depth (TVD) depict the initial structure of the rock mass: the rock parameters, the discontinuity network, and the in situ stresses. Alternating homogeneous, micritic, strong, to inhomogeneous, porous, weak limestones and massive, crystalline dolostones define the stratigraphy. Five joint sets from the cores can be distinguished into the bedding, two paleo anti‐ and synthetic normal faults and two recent strike‐slip faults. The latter, in combination with core disking, allows exclusively a strike‐slip (SS) stress regime and delimits the ratio to at least SH : Sv : Sh = 1.7 : 1.0 : 0.7. According to the results, including dilatation‐ and slip‐tendencies, drill trajectories of prosperous geothermal wells should head ESE/WNW, perpendicular to SS‐faults, and avoid the presence of normal faults. [ABSTRACT FROM AUTHOR]

Tunnel geothermal systems hold the potential to promote decarbonization of the building heating and cooling sector. They can be integrated into existing infrastructure, resulting in low additional costs. In addition, these systems have large contact areas with the ground leading to larger heat fluxes. However, tunnel geothermics is relatively unknown and rarely used. Thus, the objective of this study is to provide an overview of the two primary tunnel geothermal system types as well as their application and potential. Open hydrothermal systems use the tunnel drainage water as a heat source, whereas closed absorber systems harness the heat flux from the subsoil and the warm tunnel interior via heat exchangers. The evaluation of the global application of existing and planned tunnel geothermal systems shows that all open systems are currently located in mountainous regions with a thick rock overburden. In contrast, closed absorber systems are mostly installed in urban tunnel infrastructures. The spatial distribution of geothermal tunnel systems has a focus in central Europe with Switzerland, Germany and Austria being the countries with the highest number of installed systems. Finally, this study also presents a brief summary of existing methods to determine the geothermal potential of tunnels. [ABSTRACT FROM AUTHOR]

Based on multi‐scale and multi‐disciplinary measured data, gathered at the Geretsried geothermal site, a 3D reservoir model of the deep and fracture‐controlled Upper Jurassic carbonates in the North Alpine Foreland Basin is generated in this work. An efficient methodology is developed to numerically simulate the coupled reservoir processes of fluid flow, heat transport and thermoporoelastic stresses resulting from possible geothermal doublet operating schemes with cold fluid injection and production profiles in an enhanced naturally fractured reservoir. A variety of numerical experiments is conducted to study the reactivation potential and dilation tendency of the fracture and fault system. Simulation results show the spatiotemporal evolution of the thermoporoelastic stresses and the zone affected after 50 years of geothermal doublet operation. From these simulations, the thermoelastic response of a geothermal doublet operating with 60 °C fluid injection temperature and 20 l/s flow rate translates into a maximum induced thermal stress of around 49.4 MPa near the injection well. In terms of a long‐term reservoir performance and fault and fracture reactivation potential, the findings reveal a negligible risk to a sustainable geothermal doublet operation. [ABSTRACT FROM AUTHOR]

Copyright of GeoEcoMarina is the property of Institutul National de Cercetare-Dezvoltare pentru Geologie si Geoecologie Marina - Geoecomar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The BIM pilot project "New Köstendorf‐Salzburg Line" for ÖBB‐Infrastruktur AG covers a new twin‐track section about 21 km long involving a wide variety of different engineering structures and a corresponding need for close interdisciplinary collaboration within a sensitive project space. The pilot project successfully achieved its objective of generating a largely software‐independent overall model and transferring the knowledge gained to the Employer's Information Requirements and subsequently to a BIM execution plan. In addition to internal coordination meetings, a preliminary external meeting took place to discuss the model elements required for a government agency as part of an approval process and the availability of such elements by means of direct access to the model. By adopting an integrated, collaborative approach to project management, it was possible to define extensive procedures and workflows adapted to the needs of the respective project partners for the single‐discipline models (specialist models) and to coordinate an overall federated model. The results of the co‐ordinated overall model show the ample opportunities afforded by a parameterised ground model for transparent risk and project assessment, paving the way for a holistic, phase‐based infrastructure information model. In this regard, the authors felt that it was important to adapt the project partners' established internal procedures only minimally and to translate them into BIM‐compatible, cooperative workflows. [ABSTRACT FROM AUTHOR]

Context and background Rains, which are the main source of surface and ground water resources, provide a quantitative explanation of variations in the components of the hydrological regime in its broadest design. The Hodna watershed, situated in northeastern Algeria, is strongly marked by an arid climate highlighted by low rainfall. The latter, although weak, fall in the form of showers resulting in flooding flows. Goal and Objectives: Creating a Hydro database by multi-criteria approach is a line of research to provide a methodological framework for thematic and numeric mapping. This work is intended to establish a models of geographic hydrodatabase and models of mapping with "thematic and spatial" analysis through a GIS (Geographic Information System) approach. Methodology: The study used is to create thematic maps by combining in GIS, by representing the information collected in the form of maps and the Data tables, was carried out using the software "ArcGIS" by the exploitation of the data available at our level: DRE (Water Resources Directorate) and ANRH (National Agency of Water Resources). Results: As a result, a hydrodatabase was identified (DB), followed by the creation of Models of a Geographic Database (MGDB) for this basin and the assessment and estimation of groundwater and surface water in the Hodna Basin. The analysis of the hydrological data revealed that the surface water flow rate is influenced by physical characteristics and by meteorological parameters. The study provided firstly, the development of several maps with an improvement and an organization of information and rapid decision-making, then the Arc-GIS allows a great userfriendliness at the level of the design and at the level of the use of the application and finally access to the data is simplified, the queries are executed and the results are fed into the statistical calculations and the cartographic representation. [ABSTRACT FROM AUTHOR]

Copyright of Algerian Journal of Arid Environment (AJAE) is the property of University of Kasdi Merbah Ouargla and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the course of the preliminary planning of the new Gelnhausen–Fulda railway line which is part of the railway project Hanau–Würzburg/Fulda, two route options with tunnels, bridges, cuts and embankments are to be investigated and assessed as efficiently as possible with regard to potential geotechnical risk areas. Due to the geological and hydrogeological conditions within the north‐eastern Hessian Buntsandsteingebirge, several groundwater levels, landslides in tunnel portal areas and karstification structures are to be expected on the two route options, each of which is approx. 45 km long. In order to obtain detailed and, above all, large‐scale knowledge of geotechnical hazards of each route = in the preliminary stage of the exploration programme, geophysical surface investigations are a cost‐ and time‐optimized exploration method in addition to standard drilling. These findings as well as existing subsurface information are combined by means of BIM, so that risk areas can be identified at an early stage of the project and taken into account when selecting the most affordable route. [ABSTRACT FROM AUTHOR]

One of the major fault zones in the Semmering area runs along the Auebach Valley. In this fault zone a combination of soft fault rocks and water bearing hard rocks led to extremely challenging conditions in the design and execution of the tunnel. In difficult conditions, overlapping exploratory drillings in front of tunnel drive are essential to improve the geological‐hydrogeological model and to assess geotechnical risks. However, in the encountered geological‐hydrogeological conditions, the well‐established exploratory drilling methods reached their limits. Despite the ongoing risk analysis, a very large‐scale water and ground inflow with subsequent tunnel face collapse and development of a sinkhole on the surface occurred during the tunnelling. This paper describes the causes of the incident and the development of procedures to cope with the problem. In addition to the geological‐geotechnical analyses, the article also discusses the limitations of geotechnical surveillance in complex heterogeneous rock masses. [ABSTRACT FROM AUTHOR]

The scientific collaboration between the French and Romanian geographers has had a long and rich history of over 120 years. Over time, it has gone through more or less favorable periods, depending on the political and historical context. This paper focuses on the post-1989 era, and highlights the academic relationships between the Faculty of Geography of the University of Bucharest and universities / research centers in France, with special regard to the fields of climatology, hydrology and geomorphology. Particular attention is paid to the memory of professor Gérard Beltrando, one of the French geographers (climatologist) strongly attached to Romania and to Romanians, and who, for more than 15 years, nurtured fruitful collaborations with geographers from the University of Bucharest. [ABSTRACT FROM AUTHOR]

Scale deposit formation in drainage systems of railway tunnels represents a major challenge for their functionality and maintenance. The removal of these scale deposits causes high costs and restrictions of system availability. Effective measures to reduce scale deposit formation range from specification of the composition and structure of building materials to the application of tailored prevention and cleaning strategies. This requires advanced knowledge of the origin and type of scale deposits. The aim of this study is a systematic compilation, characterization, classification, and evaluation of scale deposits in relation to their formation mechanisms and the influence of variable environmental factors. The scale deposits from the 16 investigated tunnels mainly consist of the minerals calcite, aragonite, brucite as well as iron (hydr)oxides and detrital components. Four major types of scale deposits are distinguished: (i) unconsolidated‐particulate, (ii) shard‐like, (iii) porous, and (iv) compact scales. Types (ii) to (iv) show clear indications of microbial activity affecting the formation and appearance of individual deposits by various metabolic processes. The determining factors for the formation of scales – in addition to the geogenic composition of the aqueous solutions in the drainage system (groundwater / surface water) – are the variable interaction of these waters with the binding agents of the building materials used and the tunnel atmosphere. Geogenic conditions and technical‐operational specifications of a tunnel determine the type and character of scale deposits, which can be actively influenced based on the case‐specific reaction mechanisms by individual adaptations of environmental conditions. [ABSTRACT FROM AUTHOR]

Through decreasing hardware costs and novel areas of application, three-dimensional (3D) printing has become exceedingly popular in recent years. Starting with a project focused on public education about urban hydrology, we explored the use of 3D-printed landscape models in a number of regional applications. We also experimented with the use of 3D-printed city models to engage users through urban visualization. Our goal was to examine the role of GIS in processing geospatial data for 3D printing and to explore novel applications in physical and urban geography education and outreach. Following a brief review of related literature, this article outlines data sources for digital elevation models, boundary datasets, and building footprints with height information and the processes used to transform these into 3D-printable data files. We then describe applications focused on urban watersheds and landforms in the area of Toronto, Canada, and illustrate city models for neighbourhoods of Toronto. We found that the 3D models were favourably received by diverse types of users, from hydrology experts to environmental studies students to the general public. The overwhelmingly positive feedback generated by this project suggests that 3D-printed landscape and city models are a worthwhile strategy for improving physical and urban geography education and outreach. [ABSTRACT FROM AUTHOR]