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81.
Eslam A. Al-Hogaraty Hassan K. Garamoon Farouk El-Baz Reinhard Zölitz-Möller Mohamed A. Abdel Moati 《Arabian Journal of Geosciences》2013,6(11):4093-4107
Wadi Wurayah area is one of the major wadis originating and running on the Oman Mountains and drains into the Oman Gulf. These wadis in general and Wadi Wurayah in particular are characterized with a rich diversity of rare and mountainous and freshwater habitats and species. These wadis contain unequal, representative, and sensitive areas of the dry lands ecosystem with natural, outstanding landscapes and cultural heritage, while the socioeconomic situation indicates that it has enough socioeconomic infrastructures to develop new alternatives ecologically and economically sustainable. As most of the United Arab Emirates and the region, the study area is undergoing dramatic changes linked to economic diversification and promotion of tourism. Established under the UNESCO’s Man and the Biosphere Program, Wurayah Biosphere Reserve represents protected areas intended to demonstrate well-balanced relationship between conservation of biodiversity and an appropriate local development. The main objectives of this study are to develop an environmental information system to understand the dynamics of human activities associated to land use in the study area, highlight the threats to the environment, educate people about the basic environmental issues and positive traditional practices, and promote tourism. Based on the gained results, the concept of biosphere reserve as a model is to implement ideas of sustainable land use in practice. 相似文献
82.
Groundwater resources assessment using integrated geophysical techniques in the southwestern region of Peninsular Malaysia 总被引:2,自引:0,他引:2
Mohamed S. E. Juanah Shaharin Ibrahim Wan Nor Azmin Sulaiman Puziah Abdul Latif 《Arabian Journal of Geosciences》2013,6(11):4129-4144
Combined geophysical techniques such as multi-electrode resistivity, induced polarization, and borehole geophysical techniques were carried out on volcano-sedimentary rocks in the north of Gemas as part of the groundwater resource’s investigations. The result identifies four resistivity units: the tuffaceous mudstone, tuffaceous sandstone, the tuff bed, and the shale layer. Two types of aquifer systems in terms of storage were identified within the area: one within a fracture system (tuff), which is the leaky area through which vertical flow of groundwater occurs, and an intergranular property of the sandy material of the aquifer which includes sandstone and tuffaceous sandstone. The result also reveals that the aquifer occupies a surface area of about 3,250,555 m2 with a mean depth of 43.71 m and a net volume of 9.798?×?107?m3. From the approximate volume of the porous zone (28 %) and the total aquifer volume, a usable capacity of (274.339?±?30.177)?×?107?m3 of water in the study area can be deduced. This study provides useful information that can be used to develop a much broader understanding of the nature of groundwater potential in the area and their relationship with the local geology. 相似文献
83.
Iva frutescens is a common shrub at the upland fringe of salt marshes throughout the East and Gulf Coasts of North America. Within a marsh, its location and relative size are governed largely by the degree of flooding by seawater.Iva’s wide distribution and restricted location within salt marshes may make it a useful indicator of overall conditions of the marshes. This work was designed to provide basic information on the age and growth ofI. frutescens, especially as they relate to the degree of flooding that is needed in order to investigateIva’s potential as an indicator. Cross-sections of older stems (living and standing dead) from salt marshes in Rhode Island, United States, were examined in order to age stems and estimate their growth rate from cumulative increase in woody tissue. Most stems were six yr old or less, suggesting that aboveground structures live for only a few years. Stem diameter correlated with growth rate and aboveground biomass. Elevation at the root zone was used to estimate the duration that plants were flooded, which was negatively correlated with stem diameter. The most robust plants came from sites that were flooded only up to 6–7% of the total time during the growing season. No plants were found in areas flooded more than 30% of the time. 相似文献
84.
Norazlina Ab Halim Faradiella Mohd. Kusin Khairul Nizam Mohamed 《International Journal of Environmental Science and Technology》2018,15(4):733-742
This study was carried out to determine the concentration of heavy metals (Cd, Ni, Pb, Cr, Ni and Zn) in ordinary Portland cement (OPC) produced from the co-processing with hazardous waste in comparison with OPC produced using natural raw materials. The results showed that the concentration of heavy metals in cement produced from natural raw material was in the order of Zn > Pb > Cr > Ni > Cu > Cd. Zn and Cd were the highest and the lowest concentrations, respectively, in cements produced from the co-processing activity. The difference between heavy metals concentrations in OPC produced with and without co-processing was found to be statistically significant. The concentration of heavy metals in the cement produced is generally factory dependent. The human risk assessment associated with the heavy metals for non-carcinogenic and carcinogenic risks has been evaluated. The calculated hazard index (HI) and total lifetime cancer risks (LCR) were lower than the acceptable threshold reference values, HI < 1 and LCR < 1 × 10?4, respectively. Thus, it is anticipated that there is no potential of non-carcinogenic and carcinogenic risks for both adult and children. However, the findings indicated that there is a need for regulatory monitoring. The exposure pathway for both non-carcinogenic and carcinogenic risks are both in the order of ingestion > dermal > inhalation. 相似文献
85.
Hatem A. Ewea Nassir S. Al-Amri Mohamed A. Dawoud Amro M. Elfeki 《Natural Hazards》2018,94(2):801-817
Forecasting and monitoring extreme floods in arid regions like Saudi Arabia (SA) are a big challenge for engineers and hydrologists. It is difficult to derive reliable flood estimates at any site without adequate flood measurements. Therefore, envelope curves were developed for reliable estimates of flood peaks. Relaying on recorded flood events in SA, Francou–Rodier approach is used to develop the Regional Maximum Flood (RMF) for some wadis and for SA as a whole. A total of 3121 flood events in 32 arid basins of sizes varying from 99 to more than 4500 km2 are collected and analyzed. Results show that established regional coefficients (K) range between 2.76 and 5.5. The RMF formula for the Saudi regions is Q?=?251 A0.45. The flood-frequency analysis showed that the Log-Pearson Type III is best. The extreme observed floods for the envelope curve for K?=?5.5 accommodate floods of recurrence interval ranging between 1000 and 100,000 years. The study results provide more realistic runoff peaks for a design of flood protection works for SA watersheds and for the similar environment. Consequently, it is recommended to use the developed envelope curves and models for efficient, safe and precise hydraulic structures design in SA. 相似文献
86.
The presence of natural voids and cavities in subsurface karstic limestones causes severe problem for civil engineering and environmental management.The presence of such features hinders the extension of urbanizations particularly in the new metropolitan.The eastern part of Saudi Arabia contains various types of karstic limestone,sinkholes,solution cavities and voids.In this context,geophysical methods particularly electrical resistivity technique is used as a cost-effective solution for investigating subsurface caves,voids,and shallow weathered zones.2-D electrical resistivity data sets have been acquired along seven profiles in the new urbanization at Al Hassa area.Data processing has been carried out taking into consideration the response of synthetic models,which simulates physical models of the most common karstic features in the area.The results are very useful to determine the extension of shallow weathered zones and to locate different cavities underneath them.The hard limestone bedrock can also be detected and traced along the surveyed profiles. 相似文献
87.
Ayeldeen Mohamed Azzam Waseim Arab Mohamed G. 《Geotechnical and Geological Engineering》2022,40(4):1873-1885
Geotechnical and Geological Engineering - Urbanization and development in arid and semiarid have brought increased interest in the improvement of water sensitive soils susceptible to volume change.... 相似文献
88.
Abdelbaset S. El-Sorogy Mohamed A. Mohamed Hamdy E. Nour 《Environmental Earth Sciences》2012,67(3):777-785
In order to assess pollutants and impact of environmental changes along the Egyptian Red Sea coast, seven recent and Pleistocene coral species have been analyzed for Zn, Pb, Mn, Fe, Cr, Co, Ni, and Cu. Results show that the concentration of trace elements in recent coral skeletons is higher than those of Pleistocene counterpart except for Mn and Ni. In comparison with recent worldwide reefs, the present values are less than those of Central America coast (iron), Gulf of Aqaba, Jordan (lead, copper), Gulf of Mannar, India (chromium, zinc, manganese), Costa Rica, Panama (chromium, nickel), North-west coast of Venezuela and Saudi Arabia (copper). The present values are higher than those of Gulf of Aqaba, Jordan (iron, zinc, manganese), Gulf of Mannar, India (lead, cobalt, nickel), North-west coast of Venezuela (lead, zinc, chromium, manganese), Australia (copper, nickel, zinc, manganese). The highest values were recorded in Stylophora pistillata (iron, lead and copper), Acropora cytherea (cobalt), Pocillopora verrucosa (zinc) and the lowest concentrations were recorded in Goniastrea pectinata (iron, chromium, copper and nickel), Favites pentagona (lead, zinc and manganese), and Porites lutea (cobalt). The differences in metals content among the studied species are attributed to differences in microstructure and microarchitecture. 相似文献
89.
Ramzi Gharsalli Taher Zouaghi Mohamed Soussi Riadh Chebbi Sami Khomsi Mourad Bédir 《Comptes Rendus Geoscience》2013,345(9-10):401-417
The Cap Bon Peninsula, belonging to northeastern Tunisia, is located in the Maghrebian Alpine foreland and in the North of the Pelagian block. By its paleoposition, during the Cenozoic, in the edge of the southern Tethyan margin, this peninsula constitutes a geological entity that fossilized the eustatic, tectonic and climatic interactions. Surface and subsurface study carried out in the Cap Bon onshore area and surrounding offshore of Hammamet interests the Miocene deposits from the Langhian-to-Messinian interval time. Related to the basin and the platform positions, sequence and seismic stratigraphy studies have been conducted to identify seven third-order seismic sequences in subsurface (SM1-SM7), six depositional sequences on the Zinnia-1 petroleum well (SDM1-SDM6), and five depositional sequences on the El Oudiane section of the Jebel Abderrahmane (SDM1–SDM5). Each sequence shows a succession of high-frequency systems tract and parasequences. These sequences are separated by remarkable sequence boundaries and maximum flooding surfaces (SB and MFS) that have been correlated to the eustatic cycles and supercycles of the Global Sea Level Chart of Haq et al. (1987). The sequences have been also correlated with Sequence Chronostratigraphic Chart of Hardenbol et al. (1998), related to European basins, allows us to arise some major differences in number and in size. The major discontinuities, which limit the sequences resulted from the interplay between tectonic and climatic phenomena. It thus appears very judicious to bring back these chronological surfaces to eustatic and/or local tectonic activity and global eustatic and climatic controls. 相似文献
90.