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61.
62.
GeoJournal - The profound increase in human activities and the degrading scenario in fragile ecosystems of the western Himalayas like that of Wular Lake have highlighted the need to analyze the... 相似文献
63.
Yogendra Tandel Mohsin Jamal Chandresh Solanki Atul Desai Jignesh Patel 《Marine Georesources & Geotechnology》2017,35(4):504-511
Granular piles are frequently used as a method of improving soft grounds as they provide increased bearing capacity and reduce foundation settlements. However, in very soft clayey soils, they may not derive their load-carrying capacity by low confining pressure provided by the surrounding soil. In such circumstances, granular piles may be reinforced with suitable geosynthetic to increase its load-carrying capacity and to reduce excessive bulging. In this study, the performance of small group of geosynthetic-reinforced granular piles (GRGPs) is examined in terms of load-carrying capacity, settlement, and modulus by laboratory model tests. The parameters investigated include modulus of reinforcement material, area replacement ratio (ARR) based on the column diameter and reinforcement length. The results indicated that increasing the modulus of the reinforcement and the ARR based on the column diameter enhances the overall performance of the GRGP group. It was also observed that reinforcement on top portion of the granular pile is sufficient to substantially increase the load-carrying capacity of granular pile group. 相似文献
64.
Ismail Hilal Jamal Eddine Stitou El Messari Jesus Gabriel Moreno Navarro Mohamed Draoui 《Arabian Journal of Geosciences》2017,10(8):197
Preventive protection of surface waters against pollution and the guarantee of the best quality water are the major challenges to provide a sustainable supply of drinking water for the future generations. In this article, we present a hazard mapping application for water contamination of the dam “9 April 1947” located in the northwest of Morocco. This study was motivated by the proliferation of many pollution sources in the study area knowing that the dam feeds the region of Tanger-Asilah that has over 3 million inhabitants. The methodology used was applied for the first time in the city of Freiburg-Ebnet in Germany under the TECHNEAU project funded by the European commission and based on weighting of the different sources of contamination according to three indices: the toxicity index, quantity index, and probability index. The multiplication of the three indices has given us a hazard index named HI varying between 0 and 120 depending on the harmfulness of hazard; the later index has been used to create the final contamination hazard map. The hazard map shows 65% of the watershed area is witnessing a very low danger, 22% of the watershed area is witnessing a low danger, 10% of the watershed area is witnessing a the high danger, and 3% of the watershed area is witnessing a moderate. 相似文献
65.
Tristan D. Pearce James D. Ford Gita J. Laidler Barry Smit Frank Duerden Mishak Allarut Mark Andrachuk Steven Baryluk rew Dialla Pootoogoo Elee Annie Goose Theo Ikummaq Eric Joamie Fred Kataoyak Eric Loring Stephanie Meakin Scott Nickels Kip Shappa Jamal Shirley & Johanna Wandel 《Polar research》2009,28(1):10-27
Research on climate change impacts, vulnerability and adaptation, particularly projects aiming to contribute to practical adaptation initiatives, requires active involvement and collaboration with community members and local, regional and national organizations that use this research for policy-making. Arctic communities are already experiencing and adapting to environmental and socio-cultural changes, and researchers have a practical and ethical responsibility to engage with communities that are the focus of the research. This paper draws on the experiences of researchers working with communities across the Canadian Arctic, together with the expertise of Inuit organizations, Northern research institutes and community partners, to outline key considerations for effectively engaging Arctic communities in collaborative research. These considerations include: initiating early and ongoing communication with communities, and regional and national contacts; involving communities in research design and development; facilitating opportunities for local employment; and disseminating research findings. Examples of each consideration are drawn from climate change research conducted with communities in the Canadian Arctic. 相似文献
66.
SADIKI Moulay Lhassan EL MANSOURI Bouabid BENSEDDIK Badr CHAO Jamal KILI Malika EL MEZOUARY Lhoussaine 《地下水科学与工程》2019,(3):224-236
In arid and semi-arid zones,water is the most vulnerable resource to climate change.In fact,various techniques such as artificial recharge are adopted to restore aquifers and to ensure aquifer sustainability in relation to the accelerated pace of exploitation.Morocco is a Mediterranean country highly vulnerable to climate change,many of its main aquifers are subjected to excessive drawdowns.This technique is practiced to increase potentiality of these aquifers.In the Northwestern area of Morocco,the significant development experienced by Tangier City in the industrial,tourism,and commercial sectors will lead to increased water requirements-up to 5 067 L/s(159.8 mm^3)by 2030.However,the Charf El Akab aquifer system,subject to artificial recharge,is the only groundwater resource of Tangier region;hence,a rational management context is needed to ensure aquifer sustainability,and optimized exploitation under the background of differing constraints,such as increased water requirements,and climate change impacts.This work aims to respond,for the first time,to the Charf El Akab aquifer overexploitation problem,and to evaluate the future scenarios of its exploitation in the event of failure of one of the superficial resources.This work also presents a synthesized hydrodynamic modeling based on the results of the numerical simulations carried out using Feflow software for 2004(date of cessation of injections)and 2011(date of resumption of these facilities),making it possible to evaluate the impact of the artificial recharge on the piezometric level of the aquifer on a spatiotemporal scale.Finally,the exploitation scenarios have shown that the aquifer of Charf El Akab will not adequatly provide for the region's water requirements on the future horizon,entailing an optimal management of water resources in the region and an intentionally increased recharge rate. 相似文献
67.
Jamal Jokar Arsanjani 《International Journal of Digital Earth》2019,12(6):642-660
Global land cover maps are important sources of information for a wide range of studies including land change analysis and climate change research. While the global land cover maps attempt to present a consistent and homogenous data in terms of the production process, the existing datasets offer coarse resolution data, e.g. 1000 m for IGBP DISCover and 300 m for GlobeCover 2009 that is oftentimes challenging. Recently, GlobeLand30 data based on Landsat archive for two timestamps of 2000 and 2010 has been released. It presents a finer spatial resolution of 30 m, which provides numerous opportunities for a wide range of studies. The main objective of this study is to use this dataset for characterizing global land cover patterns, monitoring, and identifying extreme land change cases with their types and magnitude. The findings reveal massive land change patterns including deforestation, desertification, shrinkage of water bodies, and urbanization across the globe. The results and discussions of this research can help policy-makers, environmental planners, ecosystem services providers and climate change researchers to gain finer insights about the forms of global land change. Future research calls for further investigation of the underlying causes of the massive changes and their consequences on our ecosystems and human populations. 相似文献
68.
This contribution is an attempt to enlarge the current knowledge about the focal mechanisms as well as the seismotectonic
settings in Syria. The seismologically active zones have been identified by applying an appropriate methodology to the events
recorded during the period 1995–2003 by the Syrian National Seismological Network (SNSN). The recorded events in Syria were
classified as weak during the research period. It was extremely important to propose and apply an appropriate methodology
to identify the focal mechanisms generating this seismic activity. The proposed methodology consists of applying a combination
of two techniques: the multiplet and the composite focal mechanisms. The combination of many events in one composite focal
mechanism was realized by a multiplet technique using the spectral coherence of the events as a measure of similarity. The
application of the proposed methodology allows a data set of composite fault plane solutions to be obtained. Most of the composite
fault plane solutions had strike-slip mechanisms which are in agreement with the configuration of seismogenic belts in Syria. 相似文献
69.
Jamal Asfahani 《Acta Geophysica》2011,59(1):139-154
Electrical resistivity survey is conducted in the Khanasser Valley, considered as a semi-arid region in Northern Syria, to
guide and control fresh water well drilling. Vertical Electrical Soundings (VES) are carried out near the existing wells,
which were also used to measure salinity and conductivity of water samplings. Resistivity and hydrogeological data combination
made it possible to establish empirical relationships between earth resistivity, water resistivity, and the amount of total
dissolved solids (TDS). These relationships are used in the present research in order to follow the TDS salinity variations,
both in lateral and depth directions, along the longitudinal profile LP3, located in Khanasser Valley. Apparent salinity map
under this profile is established for Quaternary and Paleogene deposits, and boundaries of suitable areas for fresh water
well drilling in the totality of the Khanasser Valley are drawn. It was shown that excessive fresh-water depletion may affect
the groundwater quality by upward seepage of saline water. Therefore, it is important to keep the fresh-salt water interface
in a stationary situation. The geoelectrical methods widely contribute in determining the position of such interface, and
can be easily applied in similar arid areas. 相似文献
70.