262 research outputs found
Using tracer tests and hydrological observations to evaluate effects of tunnel drainage in the Northern Apennines (Italy)
No full textThe impact of a railway tunnel on groundwater
and surface waters in the Northern Apennines (Italy) was
demonstrated and characterised by multi-tracer tests and hydrological observations. The 15-km-long Firenzuola tunnel crosses turbidite marls and sandstones previously not considered as aquifers. During the drilling, water inrushes occurred at fracture zones, and the tunnel still continues to drain the aquifer. The water table dropped below the level of the valleys, and gaining streams transformed into losing streams or ran completely dry, as did many springs, causing severe damage to the aquatic fauna and other elements of the ecosystem. Two multitracer tests, each using uranine and sulforhodamine G, were carried out in two impacted catchments in order to confirm and quantify the stream–aquifer–tunnel interrelations. The results proved connection between losing streams and numerous water inlets in the tunnel, with maximum linear
distances of 1.4 km and velocities up to 135 m/d. Several of the demonstrated flowpaths pass under previous groundwater divides (mountain ridges), proving that the tunnel has completely modified the regional flow system. Water balance estimations demonstrate that the observed waterlosses cannot be explained by climate change but can largely be attributed to the tunnel drainage
Goldscheider (Calvin) Zuckermann (Alan S.) The Transformation of the Jews
No full textBensimon Doris. Goldscheider (Calvin) Zuckermann (Alan S.) The Transformation of the Jews. In: Archives de sciences sociales des religions, n°61/2, 1986. p. 265
Differential Hydrogeological Effects of Draining Tunnels Through the Northern Apennines, Italy
No full textWater inflows are a major challenge in tunnelling and particularly difficult to predict in geological settings consisting of heterogeneous sedimentary rock formations with complex tectonic structure. For a high-speed railway line between Bologna and Florence (Italy), a series of seven railway tunnels was drilled through turbiditic formations, ranging from pelitic rocks with thin arenitic layers over sequences including thick-bedded sandstone to calcareous rocks showing chemical dissolution phenomena (karstification). The tunnels were built as draining tunnels and caused significant impacts, such as drying of springs and base-flow losses at mountain streams. A comprehensive hydrological monitoring programme and four multi-tracer test were done, focusing on four sections of the tunnel system. The tracer tests delivered unprecedented data on groundwater flow and transport in turbiditic aquifers and made it possible to better characterize the differential impacts of tunnel drainage along a geological gradient. The impact radius is 200 m in the thin-bedded sequences but reaches 2.3-4.0 km in calcareous and thick-bedded arenitic turbidites. Linear flow velocities, as determined from the peaks of the tracer breakthrough curves, range from 3.6 m/day in the thin-bedded turbidites to 39 m/day in the calcareous rocks (average values from the four test sites). At several places, discrete fault zones were identified as main hydraulic pathways between impacted streams and draining tunnels. This case shows that ignoring the hydrogeological conditions in construction projects can cause terrible damage, and the study presents an approach to better predict hydraulic impacts of draining tunnels in complex sedimentary rock settings
Goldscheider (Calvin) Zuckermann (Alan S.) The Transformation of the Jews
No full textBensimon Doris. Goldscheider (Calvin) Zuckermann (Alan S.) The Transformation of the Jews. In: Archives de sciences sociales des religions, n°61/2, 1986. p. 265
Goldscheider (Calvin) Jewish Continuity and Change. Emerging Patterns in America
No full textAzria Régine. Goldscheider (Calvin) Jewish Continuity and Change. Emerging Patterns in America. In: Archives de sciences sociales des religions, n°64/2, 1987. p. 283
Goldscheider (Calvin) Jewish Continuity and Change. Emerging Patterns in America
No full textAzria Régine. Goldscheider (Calvin) Jewish Continuity and Change. Emerging Patterns in America. In: Archives de sciences sociales des religions, n°64/2, 1987. p. 283
Goldstein (Sidney) Goldscheider (Calvin) Jewish Americans. Three Generations in a Jewish Community
No full textBensimon Doris. Goldstein (Sidney) Goldscheider (Calvin) Jewish Americans. Three Generations in a Jewish Community. In: Archives de sociologie des religions, n°28, 1969. pp. 204-205
Multi-tracer tests to assess the impact of the new railway tunnels in Northern Tuscany, Italy, on ground and surface waters
No full textHigh-speed railway tunnels in the Northern Apennines caused large-scale groundwater drainage of turbiditic sandstone units, resulting in the drying up of springs and stream baseflow. In order to better characterise the connections between the losing streams and the tunnels, multi-tracer tests were done at four catchments, one of which is presented here. Uranine was used for all experiments and proved to be the best tracer; lithium, sulforhodamine G and tinopal CBS-X were additionally used for some experiments. The results proved connections between the streams and water inlets in the tunnels, with maximum linear distances of 1.3 km, mainly along faults. The flowpath partly run across previous water divides, suggesting that the tunnels have entirely altered the natural drainage system. Although restoration of the natural situation is impossible as long as the tunnels continue to drain the aquifer, different technical measures for the maintenance of a minimum stream baseflow were evaluated
Ecohydrogeology: The interdisciplinary convergence needed to improve the study and stewardship of springs and other groundwater-dependent habitats, biota, and ecosystems
No full textThis essay discusses the need for, advantages and challenges of integrating the scientific disciplines of ecology and hydrogeology in the study of groundwater-dependent ecosystems (GDEs). We provide a definition for ecohydrogeology as “a unifying, synthetic field of study integrating the approaches from the ecological and hydrogeological sciences in the study of groundwater (GW)-related ecosystems, habitats, and organisms to advance science, stewardship, and policy”. We selected specific case studies to illustrate first how hydrogeological approaches can favour in-depth understanding and modelling of springs and crenobiontic (spring-dependent) species distribution, assemblage composition and organization. Second, this essay also examines how taxa and assemblages serve as bioassays and ecosystem indicators to infer hydrogeological aspects of GW flow and discharge, as well as quantitative and qualitative human impacts. We consider both types of features and parameters as ecohydrogeological indicators. The examples presented include topics related to springs and other GDE geomorphological types and classification, GW quality influences on crenobiont distribution, phreatophyte (= plant species the roots of which reach to and into the water table) ecophysiology in relation to water table depth, and flow variability in karstic systems, to nutrient dynamics in relation to dinoflagellate blooms in GDE montane lakes. Conceptual approaches that integrate ecology with hydrogeology include the investigation of GDE distribution and ecology, groundwater-surface water (GW-SW) interactions, and the development of the discipline of ecohydrology. Despite widespread applications, the scientific community still lacks a complete or effective integration of the principles described in the fields of groundwater hydrogeology with ecology, ecophysiology, and environmental biology. Springs are aquatic-wetland-riparian habitats that link shallow subsurface-surface processes and assemblages, often functioning as biodiversity hotspots, ecotones, keystone, and refugial ecosystems, for which coordination between studies of hydrogeology and ecology are both obvious and essential. Over the past century, springs ecosystem ecology has been largely ignored by hydrologists, and, conversely, hydrogeology has been under-emphasized by ecologists. Recent global recognition of the extraordinary biodiversity and socio-cultural significance of springs, coupled with their globally highly threatened conservation status, stimulated this inquiry into how to better integrate hydrogeology with springs ecosystem ecology. Acknowledging the highly threatened status of springs ecosystems around the world, there is an urgent need to integrate and invigorate the union of these disciplines into ecohydrogeology, the study of groundwater-dependent organisms, habitats, ecosystems, and management policy
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