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Soil-water dynamics and tree water uptake in the Sacramento Mountains of New Mexico (USA): a stable isotope study | Interaction sol-eau et prélèvement d’eau par les arbres dans les montagnes de Sacramento dans le Nouveau Mexique (Etats-Unis d’Amérique): une étude des isotopes stables La dinámica del agua del suelo y la captación de agua de árboles en las montañas de Sacramento en Nuevo México (EEUU): un estudio de isótopos estables (美国)新墨西哥州萨克拉门托山脉土壤水动力学和树的水摄取 Dinâmicas solo-água e absorção de água por árvore nas Montanhas de Sacramento no Novo México (EUA): um estudo de isótopos estáveis Полный текст
2016
Gierke, Casey | Newton, B Talon | Phillips, Fred M.
In the southwestern United States, precipitation in the high mountains is a primary source of groundwater recharge. Precipitation patterns, soil properties and vegetation largely control the rate and timing of groundwater recharge. The interactions between climate, soil and mountain vegetation thus have important implications for the groundwater supply. This study took place in the Sacramento Mountains, which is the recharge area for multiple regional aquifers in southern New Mexico. The stable isotopes of oxygen and hydrogen were used to determine whether infiltration of precipitation is homogeneously distributed in the soil or whether it is partitioned among soil-water ‘compartments’, from which trees extract water for transpiration as a function of the season. The results indicate that “immobile” or “slow” soil water, which is derived primarily from snowmelt, infiltrates soils in a relatively uniform fashion, filling small pores in the shallow soils. “Mobile” or “fast” soil water, which is mostly associated with summer thunderstorms, infiltrates very quickly through macropores and along preferential flow paths, evading evaporative loss. It was found that throughout the entire year, trees principally use immobile water derived from snowmelt mixed to differing degrees with seasonally available mobile-water sources. The replenishment of these different water pools in soils appears to depend on initial soil-water content, the manner in which the water was introduced to the soil (snowmelt versus intense thunderstorms), and the seasonal variability of the precipitation and evapotranspiration. These results have important implications for the effect of climate change on recharge mechanisms in the Sacramento Mountains.
Показать больше [+] Меньше [-]Ecological snapshot of a population of Panopea within their traces (Pliocene, Agua Amarga subbasin, SE Spain) Полный текст
2019
Łaska, Weronika | Rodríguez-Tovar, Francisco J. | Uchman, Alfred | Aguirre, Julio
Pliocene deposits cropping out in the Agua Amarga subbasin (Almería, SE Spain) include a composite shell bed made up of variously preserved and densely packed mollusks. The characteristics of the shell bed indicate deposition in shallow marine settings under a changeable sedimentation rate. The composite shell bed was formed through the amalgamation of several depositional events, mostly connected with storm events. During relatively slow sedimentation the bivalve Panopea colonized the substratum. The colonization took place over different stages of the shell bed formation, as reflected by differently preserved Panopea scattered throughout the shell bed. The upper part of the shell bed contains several tens of Panopea preserved within their burrows: Scalichnus cf. phiale Hanken et al., 2001. All bivalves in S. cf. phiale are articulated and preserved in life position. They are confined to a single horizon and most probably represent a single fossil population composed of adult individuals of Panopea resulting from anastrophic burial by storm deposits. As a consequence, the bivalves in their burrows succumbed at the same time; that is, the study case represents an “ecological snapshot” or ecological census.
Показать больше [+] Меньше [-]Summer rainstorm associated with a debris flow in the Amarilla gully affecting the international Agua Negra Pass (30°20′S), Argentina Полный текст
2017
Lauro, Carolina | Moreiras, StellaM. | Junquera, Sebastian | Vergara, Ivan | Toural, Rafael | Wolf, Johannes | Tutzer, Ruben
The Central-West region of Argentina was seriously affected by a series of convective summer storms on January–February of 2013 generating many debris flows and rockfall in the Central Andes mountain regions. In particular, the unreported 8th February event caused the sad death of a 10-year-old child being completely ignored by society and local authorities. Despite this, meteorological conditions associated with this event and further episodes were rarely measured and determined mainly due to scarce meteorological stations in Andean mountain areas. In this paper, meteorological data from CMORPH algorithm and measurements of surrounding gauges were analyzed for estimating the triggering precipitation value of this event. As well, the particular debris flow channeled into the main branch of the Amarilla gully in the Agua Negra valley was geomorphologically described. The amount of precipitation associated with this debris flow was 5.5 and 13.2 mm accumulated previous to the event. This violent debris flow was generated in a talus zone in a periglacial environment located just below a covered rock glacier. However, the influence of the permafrost thawing in this process is not feasible. The altitude of the 0 °C isotherm was lower during the previous days of the event, and no monitoring on permafrost is available for this area. The volume of removed mass was estimated in 5 × 10⁴ m³, and the mean velocity was 35 km/h. Boulders of 4 m diameter were found in the source area, while the deposit is up to 75% sandy with clasts that hardly exceed 10 cm in the alluvial fan distal part. Herein the main objective is to advice about the probable catastrophic impact of similar events in the future. These findings could be useful for hazard remediation, mitigation, and prevention plans for the Agua Negra international pass under construction.
Показать больше [+] Меньше [-]Défis présents et futurs pour les systèmes urbains affectés par l’eau de mer et son intrusion: le cas de Venise, Italie Desafíos actuales y futuros de los sistemas urbanos afectados por agua salada y su intrusión: el caso de Venecia, Italia 受 海水及其入侵影响的城市系统研究现状及展望---以意大利威尼斯为例 Desafios presentes e futuros dos sistemas urbanos afectados por água marinha e sua intrusão: o caso de Veneza, Itália | Present and future challenges of urban systems affected by seawater and its intrusion: the case of Venice, Italy Полный текст
2011
In lagoonal and marine environments, both historic monuments and recent buildings suffer from severe salt damage caused by sea flooding, sea-level rise and frequent storm events. Salt-water contamination of groundwater systems, a widespread phenomenon typical of coastal areas, can lead to a deterioration not only of the quality of fresh groundwater resources, but also of building materials in urban settlements. A general overview is given of the hydrogeological configuration of the subsoil of Venice (Italy), with particular reference to the shallow groundwater circulation. The relationship between the seawater in the subsoil and salt decay processes, due to salt crystallization, is highlighted. These processes affect civil constructions in Venice’s historic center. Perched aquifers, influenced by tide variations and characterized by salt-water intrusion, favor the transport of salts within masonry walls through the action of rising damp. In fact, foundations, in direct contact with the aquifers, may become a preferential vehicle for the transportation of salt within buildings. Decay patterns of different building materials can be detected through non-destructive techniques, which can identify sea-salt damage and therefore assist in the preservation of cultural heritage in coastal areas.
Показать больше [+] Меньше [-]Controls over hydrogen and oxygen isotopes of surface water and groundwater in the Mun River catchment, northeast Thailand: implications for the water cycle | Contrôle par les isotopes de l’hydrogène et l’oxygène des eaux de surface et souterraines dans le bassin de la rivière Mun, nord-est de la Thaïlande: conséquences pour le cycle de l’eau Controles sobre los isótopos de hidrógeno y oxígeno de las aguas superficiales y subterráneas en la cuenca del río Mun, noreste de Tailandia: implicancias para el ciclo del agua 泰国东北部Mun河流域地表水与地下水中氢氧同位素的控制:对水循环的启示 Controles sobre os isótopos de hidrogênio e oxigênio nas águas superficiais e subterrâneas da bacia do Rio Mun, nordeste da Tailândia: implicações para o ciclo hidrológico Полный текст
2020
Yang, Kunhua | Han, Guilin
Stable isotopic composition (δ²H, δ¹⁸O) of river water, groundwater, and paddy water in the Mun River catchment, northeast Thailand, were determined to investigate the hydrological processes and the impacts of natural and anthropogenic activities on the water cycle. Quantities of δ²H (−93.9 to −25.4‰) and δ¹⁸O (−12.24 to −2.22‰) in river water in the wet season follow the trend: upper reaches > middle reaches ≈ lower reaches. Trends for δ²H (−52.3 to −22.0‰) and δ¹⁸O (−6.37 to −1.36‰) in the dry season are: upper reaches ≈ middle reaches > lower reaches. In the dry season, groundwater (δ²H: −57.5 to −34.6‰, δ¹⁸O: −8.24 to −4.40‰) shows a lighter isotopic composition, and paddy water (δ²H: −18.2‰, δ¹⁸O: −0.72‰) shows the highest isotopic composition. Spatial variation of δ¹⁸O and deuterium excess suggests that groundwater exchanges with surface water frequently. Rainfall and river water recharge groundwater in the wet season, and groundwater flows back to the river in the dry season, especially in the middle reaches. This process is most likely related to impoundment of the rivers by large dams. On the other hand, the lowest values of stable isotopes of river water are coincident with the extreme flooding that was produced by Tropical Storm Sonca in July 2017. This study contributes to a better understanding of hydrological processes in the Mun River catchment and provides a perspective on the application of stable isotopes to other large tropical monsoon catchments around the world.
Показать больше [+] Меньше [-]Building Resilience : Integrating Climate and Disaster Risk into Development | Crear resiliencia mediante la integración de los riesgos climáticos y de desastre en el proceso de desarrollo - Resumen ejecutivo (Vol. 2) | Renforcement de la résistance aux chocs climatiques : Intégrer la dimension climatique et les risques de catastrophes dans les plans de développement - Les leçons de l’expérience du Groupe de la Banque mondiale | Caudal : revista sectorial de agua y saneamiento - Bolivia | Promouvoir la bonne gouvernance par les fonds sociaux et la d?ntralisation Полный текст
2013
World Bank
This report presents the World Bank Group's experience in climate and disaster resilient development and contends that it is essential to eliminate extreme poverty and achieve shared prosperity by 2030. The report argues for closer collaboration between the climate resilience and disaster risk management communities through the incorporation of climate and disaster resilience into broader development processes. Selected case studies are used to illustrate promising approaches, lessons learned, and remaining challenges all in contribution to the loss and damage discussions under the United Nations Framework Convention on Climate Change (UNFCCC). The introduction provides an overview of the UNFCCC and also introduces key concepts and definitions relevant to climate and disaster resilient development. Section two describes the impacts of globally increasing weather-related disasters in recent decades. Section three summarizes how the World Bank Group's goals to end extreme poverty and boost shared prosperity are expected to be affected by rising disaster losses in a changing climate. Section four discusses the issue of attribution in weather-related disasters, and the additional start-up costs involved in climate and disaster resilient development. Section five builds upon the processes and instruments developed by the climate resilience and the disaster risk management communities of practice to provide some early lessons learned in this increasingly merging field. Section six highlights case studies and emerging good practices in climate and disaster resilient development. Section seven concludes the report, summarizing key lessons learned and identifying potential gaps and avenues for future work. | En el informe “Crear resiliencia mediante la integración de los riesgos climáticos y de desastre en el proceso de desarrollo” se muestra por qué es esencial desarrollar la resiliencia al clima para poder alcanzar los objetivos del Grupo del Banco Mundial de poner fin a la pobreza extrema y promover la prosperidad compartida. En este resumen ejecutivo se hace un llamado a la comunidad internacional del desarrollo a trabajar en diversas disciplinas y sectores con el propósito de generar una mayor resiliencia de largo plazo, reducir los riesgos y evitar mayores costos en el futuro. Se hace hincapié en la necesidad de crear instituciones y dotarlas de los medios para emprender la continua labor que se requiere para lograr un desarrollo en que se tenga en cuenta la resiliencia al clima y a los desastres. Al destacar las mejores prácticas, el informe muestra cómo los instrumentos financieros y los programas de intervención, sumados a la experiencia y conocimientos especializados en preparación para casos de desastre adquiridos durante décadas, están ayudando a las naciones a prepararse para un mundo más expuesto a los cambios. Asimismo, en el informe se reconoce que un desarrollo con tales características tiene costos iniciales adicionales, que se amortizan en el largo plazo si se actúa correctamente. En este contexto, el informe propugna una colaboración más estrecha entre las comunidades responsables de crear resiliencia al clima y las encargadas de administrar los riesgos de desastre, y la incorporación de la resiliencia al clima y a los desastres en los procesos de desarrollo en sentido más amplio. Presenta estudios de casos seleccionados para mostrar algunos enfoques promisorios, las lecciones aprendidas y los desafíos que aún existen. | Le présent rapport explique pourquoi le renforcement de la résistance aux chocs climatiques est une condition essentielle à la réalisation des objectifs du Groupe de la Banque mondiale — mettre fin à la pauvreté extrême et promouvoir une prospérité partagée — et pourquoi il devrait constituer la clé de voûte du programme mondial de développement. À défaut d’aider les pays, les régions et les villes pauvres et vulnérables à se préparer et à s’adapter aux risques climatiques actuels et futurs, nous risquons de mettre en péril des décennies d’acquis du développement. Nous espérons que ce rapport, en s’appuyant sur l’expérience de la Banque mondiale en matière de résistance aux chocs climatiques et de préparation aux catastrophes naturelles, contribuera utilement au débat international en cours sur les moyens de lutte contre les pertes et les dommages occasionnés par le changement climatique. Le rapport reconnaît cependant qu’un tel développement exige au départ des financements supplémentaires qui s’avéreront rentables à long terme si les choses sont faites correctement. Dans ce contexte, le rapport préconise un renforcement de la collaboration entre les collectivités engagées dans l’application de mesures de résistance aux chocs climatiques et de gestion des risques de catastrophe, ainsi que l’intégration de ces mesures dans le cadre plus large de leurs processus de développement. Le rapport s’appuie sur diverses études de cas pour illustrer les démarches prometteuses, les enseignements tirés de l’expérience et les difficultés qui restent à surmonter. Le rapport entend contribuer au débat engagé dans le cadre de la Convention-cadre des Nations Unies sur les changements climatiques au sujet des pertes et des préjudices liés aux effets néfastes des changements climatiques. Il s’adresse principalement aux professionnels du développement et aux décideurs nationaux qui doivent composer avec le défi posé par une aggravation possible des catastrophes causées par l’évolution graduelle des conditions climatiques moyennes et extrêmes.
Показать больше [+] Меньше [-]Long-term spatio-temporal precipitation variability in arid-zone Australia and implications for groundwater recharge | Variabilité spatiotemporelle sur le long terme des précipitations en zone aride en Australie et conséquences sur la recharge Variabilidad espacio-temporal a largo plazo de la precipitación en una zona árida de Australia y las implicancias en la recarga del agua subterránea 澳大利亚干旱地区降水长期的时空变化及对地下水补给的影响 Variabilidade espaço-temporal da precipitação em longo prazo em uma região árida da Austrália e suas implicações na recarga das águas subterrâneas Полный текст
2016
Acworth, R Ian | Rau, Gabriel C. | Cuthbert, Mark O. | Jensen, Evan | Leggett, K.
Quantifying dryland groundwater recharge as a function of climate variability is becoming increasingly important in the face of a globally depleted resource, yet this remains a major challenge due to lack of adequate monitoring and the complexity of processes involved. A previously unpublished and unique dataset of high density and frequency rainfall measurements is presented, from the Fowlers Gap Arid Zone Research Station in western New South Wales (Australia). The dataset confirms extreme spatial and temporal variability in rainfall distribution which has been observed in other dryland areas and is generally explained by the dominance of individual storm cells. Contrary to previous observations, however, this dataset contains only a few localised storm cells despite the variability. The implications of spatiotemporal rainfall variability on the estimation of groundwater recharge is assessed and show that the most likely recharge mechanism is through indirect and localised, rather than direct, recharge. Examples of rainfall and stream gauge height illustrate runoff generation when a spatially averaged threshold of 15–25 mm (depending on the antecedent moisture conditions) is exceeded. Preliminary assessment of groundwater levels illustrates that the regional water table is much deeper than anticipated, especially considering the expected magnitude of indirect and localised recharge. A possible explanation is that pathways for indirect and localised recharge are inhibited by the large quantities of Aeolian dust observed at the site. Runoff readily occurs with water collecting in surface lakes which slowly dry and disappear. Assuming direct groundwater recharge under these conditions will significantly overestimate actual recharge.
Показать больше [+] Меньше [-]L’ aquifère crétacé profond des bassins Aleppo et Steppe de Syrie : estimation de l’origine météorique et de la source géographique de l’eau de nappe El acuífero Cretácico profundo en las cuencas de Aleppo y Steppe de Siria: evaluación del origen meteórico y la fuente geográfica del agua subterránea 叙利亚Aleppo和Steppe流域的深部白垩系含水层:评价地下水的大气降水起源和地理来源 O aquífero cretácico profundo nas bacias de Aleppo e Steppe da Síria: avaliação da origem meteórica e geográfica das águas subterrâneas | Thedeep Cretaceous aquifer in the Aleppo and Steppe basins of Syria: assessment of the meteoric origin and geographic source of the groundwater Полный текст
2012
Stadler, S. | Geyh, M. A. | Ploethner, D. | Koeniger, P.
A drilling project was carried out in Syria to assess the potential of the deep groundwater resources of the Cretaceous aquifer, composed of Cenomanian-Turonian limestones and dolomites. In this context, isotope (14C, 3H, δ13C, δ18O, δ2H) and hydrochemical analyses were performed on wells in and around the Aleppo and Steppe basins. The interpretation includes complementary results from published and unpublished literature. The results provide evidence that many new wells pump mixed groundwater from the Cretaceous aquifer and the overlying Paleogene aquifer. Radiocarbon measurements confirmed dominating Pleistocene groundwater in the Cretaceous aquifer and mainly Holocene groundwater in the Paleogene aquifer. Most groundwater in the Cretaceous aquifer seems to be recharged in the western limestone ridges, stretching from Jebel az Zawiyah (south of Idlep) via Jebel Samane (south of Afrin and A’zaz) to the region north of Aleppo, and in the Northern Palmyrides mountain belt. Some recharge also occurs around the basalt plateau of the Jebel al Hass, south east of Aleppo. It is concluded that the Taurus Mountains and the Euphrates River do not recharge the Cretaceous aquifer. The sources of recharge seem to be occasionally occurring intensive winter storms that approach from Siberia.
Показать больше [+] Меньше [-]Groundwater response to serial stream stage fluctuations in shallow unconfined alluvial aquifers along a regulated stream (West Virginia, USA) | Réponse des eaux souterraines à des fluctuations hydrologiques d’un cours d’eau au sein d’aquifères alluviaux libres peu profonds le long d’un cours d’eau régulé (Virginie occidentale, Etats-Unis d’Amérique). Respuesta del agua subterránea a una serie de escenarios de fluctuaciones de una corriente en acuíferos aluviales someros no confinados a lo largo de una corriente regulada (West Virginia, EEUU) (美国西佛吉尼亚州)沿管控河流区域浅层非承压冲积含水层地下水对连续河水位波动的响应 Resposta das águas subterrâneas a uma série de estágios de flutuação em aquíferos aluviais rasos não confinados ao longo um rio regulado (Virgínia Ocidental, EUA) Полный текст
2016
Groundwater response to stream stage fluctuations was studied in two unconfined alluvial aquifers using a year-long time series of stream stages from two pools along a regulated stream in West Virginia, USA. The purpose was to analyze spatial and temporal variations in groundwater/surface-water interaction and to estimate induced infiltration rate and cumulative bank storage during an annual cycle of stream stage fluctuation. A convolution-integral method was used to simulate aquifer head at different distances from the stream caused by stream stage fluctuations and to estimate fluxes across the stream–aquifer boundary. Aquifer diffusivities were estimated by wiggle-matching time and amplitude of modeled response to multiple observed storm events. The peak lag time between observed stream and aquifer stage peaks ranged between 14 and 95 hour. Transient modeled diffusivity ranged from 1,000 to 7,500 m²/day and deviated from the measured and calculated single-peak stage-ratio diffusivity by 14–82 %. Stream stage fluctuation displayed more primary control over groundwater levels than recharge, especially during high-flow periods. Dam operations locally altered groundwater flow paths and velocity. The aquifer is more prone to surface-water control in the upper reaches of the pools where stream stage fluctuations are more pronounced than in the lower reaches. This method could be a useful tool for quick assessment of induced infiltration rate and bank storage related to contamination investigations or well-field management.
Показать больше [+] Меньше [-]Inferring groundwater flow and recharge from time series analysis of storm responses in a karst aquifer of southeastern Kentucky (USA) | Déduction de l'écoulement des eaux souterraines et de la recharge à partir de l’analyse des séries chronologiques des réponses aux orages dans un aquifère karstique du sud-est du Kentucky (USA) Inferencia del flujo de agua subterránea y la recarga a partir del análisis de series de tiempo de las respuestas de tormentas en un acuífero kárstico del sudeste de Kentucky (EE. UU.) 通过对(美国)肯塔基州东南部一岩溶含水层暴雨响应的时间序列分析推断地下水流和补给 Determinação do fluxo e recarga das águas subterrâneas a partir da análise de series históricas de tempestades em um aquífero cárstico no sudeste de Kentucky (EUA) Полный текст
2018
Tagne, G. V. | Dowling, C.
Epigenic karst systems exhibit strong connectivity to surface recharge. In land use dominated by extensive agriculture and farming, epigenic karst aquifers are highly vulnerable to surface contaminants from point and nonpoint sources. Currently, the karstic landscapes of the southeastern Kentucky platform (USA) are impacted by agriculture and the rapid proliferation of concentrated-animal-feeding operations. Analysis of karst aquifer responses to storm events provides qualitative information regarding aquifer–recharge flow paths and groundwater residence time, and knowledge of spatial and temporal variations in recharge and flow is crucial to the understanding of the fate of surface contaminants. Time-series correlation analyses on long-term physicochemical data recorded at the outlet of Grayson Gunnar Cave, an epigenic karst system located along the Cumberland escarpment in southeastern Kentucky, revealed the existence of two separate conduit branches responding 4–8 h apart from each other. Recorded storm response times range from 4 h for flushing and dilution to 7 h for recovery. An estimated 6 million L of stored groundwater is discharged from both branches during major storms, and the fastest responding branch accounts for the majority (80%) of the groundwater reserve being discharged through the spring. As evidenced by groundwater residence time (7 days), recharge is likely characterized by localized infiltration of rain water from subsurface sinkholes to the conduit branches with no contribution of regional or lateral groundwater flow.
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