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61.
Rahman A. T. M. Sakiur Hosono Takahiro Tawara Yasuhiro Fukuoka Youichi Hazart Aurelien Shimada Jun 《Hydrogeology Journal》2021,29(5):1885-1904
Hydrogeology Journal - Integrated watershed modeling techniques have been applied in recent years to examine surface and subsurface interactions. Model performance is often evaluated by best fit of... 相似文献
62.
Brückner Florian Bahls Rebecca Alqadi Mohammad Lindenmaier Falk Hamdan Ibraheem Alhiyari Mohammad Atieh Ala’a 《Hydrogeology Journal》2021,29(8):2789-2802
Hydrogeology Journal - In 2017, a comprehensive review of groundwater resources in Jordan was carried out for the first time since 1995. The change in groundwater levels between 1995 and 2017 was... 相似文献
63.
Khoshghalb Arman Nobarinia Mohammad Stockton Joshua Kalateh Farhoud 《Acta Geotechnica》2021,16(5):1635-1645
Acta Geotechnica - The purpose of this study is to conduct hole erosion tests (HETs) to better understand the progression of concentrated leaks in compacted soils. While samples with high levels of... 相似文献
64.
Parvin Sultana Paul Michael Thompson Naya Sharma Paudel Madan Pariyar Mujibur Rahman 《Climate Policy》2019,19(6):S94-S106
ABSTRACTSince the 1990s, climate change impact discourse has highlighted potential for large scale violent conflicts. However, the role of climate stresses on local conflicts over natural resources, the role of policies and adaptation in these conflicts, and opportunities to enhance cooperation have been neglected. These gaps are addressed in this paper using evidence from participatory action research on 79 cases of local collective action over natural resources that experience conflicts in Bangladesh and Nepal. Climate trends and stresses contributed to just under half of these conflict cases. Nine factors that enable greater cooperation and transformation of conflict are identified. Participatory dialogue and negotiation processes, while not sufficient, changed understanding, attitudes and positions of actors. Many of the communities innovated physical measures to overcome natural resource constraints, underlying conflict, and/or institutional reforms. These changes were informed by improving understanding of resource limitations and indigenous knowledge. Learning networks among community organizations encouraged collective action by sharing successes and creating peer pressure. Incentives for cooperation were important. For example, when community organizations formally permitted excluded traditional resource users to access resources, those actors complied with rules and paid towards management costs. However, elites were able to use policy gaps to capture resources with changed characteristics due to climate change. In most of the cases where conflict persisted, power, policy and institutional barriers prevented community-based organizations from taking up potential adaptations and innovations. Policy frameworks recognizing collective action and supporting flexible innovation in governance and adaptation would enable wider transformation of natural resource conflicts into cooperation.Key policy insights
Climate stresses, policy gaps and interventions can all worsen local natural resource conflicts.
Sectoral knowledge and technical approaches to adaptation are open to elite capture and can foster conflicts.
Many local natural resource conflicts can be resolved but this requires an enabling environment for participatory dialogue, external facilitation, flexible responses to context, and recognition of disadvantaged stakeholder interests.
Transforming conflict to greater cooperation mostly involves social and institutional changes, so adaptation policies should focus less on physical works and more on enabling factors such as negotiation, local institutions, knowledge, and incentives.
65.
The problem of drained cavity expansion in soils of finite radial extent is investigated. Cylindrical and spherical cavities expanded from zero radius subjected to either constant stress or zero displacement at the finite boundary are considered. The generalised analytical solution procedure presented enables more advanced constitutive models to be implemented than have been possible in previous studies. Results generated for Sydney quartz sand highlight substantial differences between cavity limit pressures for the two boundary conditions and for boundaries of finite and infinite radial extent. This is of significance in accounting for boundary effects when interpreting cone penetration tests conducted in calibration chambers. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
66.
Benoît Thibodeau Moritz F. Lehmann Jacqueline Kowarzyk Alfonso Mucci Yves Gélinas Denis Gilbert Roxane Maranger Mohammad Alkhatib 《Estuarine, Coastal and Shelf Science》2010
Water column concentrations and benthic fluxes of dissolved inorganic nitrogen (DIN) and oxygen (DO) were measured in the Gulf of St. Lawrence and the Upper and Lower St. Lawrence Estuary (USLE and LSLE, respectively) to assess the nitrogen (N) budget in the St. Lawrence (SL) system, as well as to elucidate the impact of bottom water hypoxia on fixed-N removal in the LSLE. A severe nitrate deficit, with respect to ambient phosphate concentrations (N*∼−10 μmol L−1), was observed within and in the vicinity of the hypoxic bottom water of the LSLE. Given that DO concentrations in the water column have remained above 50 μmol L−1, nitrate reduction in suboxic sediments, rather than in the water column, is most likely responsible for the removal of fixed N from the SL system. Net nitrate fluxes into the sediments, derived from pore water nitrate concentration gradients, ranged from 190 μmol m−2 d−1 in the hypoxic western LSLE to 100 μmol m−2 d−1 in the Gulf. The average total benthic nitrate reduction rate for the Laurentian Channel (LC) is on the order of 690 μmol m−2 d−1, with coupled nitrification-nitrate reduction accounting for more than 70%. Using average nitrate reduction rates derived from the observed water column nitrate deficit, the annual fixed-N elimination within the three main channels of the Gulf of St. Lawrence and LSLE was estimated at 411 × 106 t N, yielding an almost balanced N budget for the SL marine system. 相似文献
67.
Prof. Dr. K. Hinz Dr. J. Fritsch Dr. E. H. K. Kempter Mr. A. Manaf Mohammad Dr. J. Meyer Mr. D. Mohamed Dipl. Geophys. H. Vosberg Dipl. Ing. J. Weber Mr. J. Benavidez 《International Journal of Earth Sciences》1989,78(3):705-730
Widely accepted plate tectonic models suggest that an inactive subduction zone lies along the north-west continental margin of Sabah. In contrast, interpretation of reflection seismic data acquired by BGR shows an autochthonous continental terrane comprising an Oligocene to Early Miocene carbonate platform being progressively overthrust by an allochthonous rock complex. Progressive compression resulted in the development of four structural zones: Imbricated thrust sheets (Zone III); two thrust sheet systems one on top of the other (Zone IV); a complex zone with multiphase deformation (Zone V); and piercement ridges (Zone VI).
Zusammenfassung Nach herkömmlichen plattentektonischen Vorstellungen soll eine inaktive Subduktionszone am nordwestlichen Kontinentalrand von Sabah liegen. Reflexionsseismische Meßdaten der BGR zeigen jedoch, daß hier autochthone kontinentale Kruste mit einer oligozänen-frühmiozänen Karbonatplattform progressiv von einem allochthonen Gesteinsverband überschoben wird. Fortschreitender Zusammenschub seit dem frühen Miozän führte zur Anlage von vier Deformationszonen: Tekonische Schuppen (Zone III); zwei übereinander geschobene Verschuppungssysteme (Zone IV); Gürtel mit mehrphasiger Deformation (Zone V) und Durchspießungsstrukturen (Zone VI).
Résumé Les modèles géodynamiques que l'on admet habituellement comportent une zone de subduction inactive le long de la marge continentale nord-occidentale de Sabah. Toutefois, des mesures de sismique-réflexion exécutées par le BGR font apparaître qu'à cet endroit, une croûte continentale autochtone, comportant une plateforme carbonatée oligocène à éomiocène, est chevauchée progressivement par un complexe allochtone. La compression, qui s'est manifestée progressivement depuis le Miocène inférieur, a engendré quatre zones structurales: un ensemble d'écailles tectoniques (zone III); deux systèmes de lames tectoniques charriés l'un sur l'autre (zone IV); une zone complexe à déformation multiphasée (zone V); des structures d'extrusion tectonique (zone VI).
, - Sabah'a. , - . 4-? : ( 3), ( 4) ( 5) ( 6).相似文献
68.
Mohammad Qausar 《Pure and Applied Geophysics》1989,131(4):703-713
The attenuation properties of eight rheological models have been studied theoretically. The expressions forQ have been obtained by using dissipated and stored energies and/or complex modulus for each model. The dependence ofQ on frequency has been demonstrated. The three-element elastic model appears to be the best one to represent the viscoelastic nature of the earth's material for a finite value ofQ. 相似文献
69.
Mushtaqur Rahman 《GeoJournal》1993,31(4):363-371
Present irrigation practices and water management techniques in Pakistan are the result of a long process. Through a cultural-historical approach, generic relationships of some present patterns are traced to their origin. The origin of irrigation was probably in small alluvial valleys of Southwest Asia, which is also considered the hearth of seed agriculture. From a simple beginning the irrigation and water management systems have become extremely complicated to support Pakistan's largest irrigation network in the world.Part of the research for this paper was done at the Department of Geography, South Asia Institute, University of Heidelberg, Heidelberg, Germany during the summer of 1992. 相似文献
70.