Paleo and recent earthquakes have been recorded in Wadi Hagul area and its environs, which have left behind geologic structures of deformation preserved in exposed sedimentary rocks. To evaluate such deformation and s...Paleo and recent earthquakes have been recorded in Wadi Hagul area and its environs, which have left behind geologic structures of deformation preserved in exposed sedimentary rocks. To evaluate such deformation and surface break, different techniques and data types are used compromising image processing techniques, Geographic Information Systems (GIS), seismicity data, as well as, field investigation. The field investigation clarified that the study area is enriched with soft-sediment deformation structures encompassing two types of geologic structures;brittle and viscoplastic structures. The analysis of the various types of data elucidate that, the earthquakes of Wadi Hagul are frequently distributed at an average depth ranging from (1 to 35 km) within the top of the Earth’s crust which are mainly controlled by existing Hagul fault zone. The study gives new insight for a better understanding of the seismic activity in the study area which helps in the seismic hazard展开更多
The present study provides a vegetation analysis and species distribution at 50 sites, emphasizing the environmental factors that affect species distribution. A total of 74 plant species belonging to 67 genera and rel...The present study provides a vegetation analysis and species distribution at 50 sites, emphasizing the environmental factors that affect species distribution. A total of 74 plant species belonging to 67 genera and related to 23 families of vascular plants are recorded. Asteraceae, Poaceae, Chenopodiaceae, Brassicaceae, Fabaceae and Zygophyllaceae are the largest families, and therophytes (41.89) and chamaephytes (24.32%) are the most frequent, indicating a typical desert life-form spectrum. Chorological analysis revealed that 25 of the studied species were Mediterranean taxa, Saharo-Sindian chorotypes, either pure or penetrated into other regions, comprised 47 species. After application of the TWINSPAN and DCA programs, 4 vegetation groups (A-D) were identified, groups A and B were dominated by Achillea santolina, group C was codominated by Zygophyllm coccinum and Launaea spinosa and group D was dominated by Leptadenia pyrotechnica. Groups A and B may represent the vegetation types of the Western Mediterranean coast of Egypt, while groups C and D may represent the Wadi Hagul. The linear correlation of soil variables with the importance values of some dominant species and the application of Canonical Correspondence Analysis (CCA-biplot) indicates significant associations between the floristic composition of the studied area and the edaphic factors such as electrical conductivity, pH, calcium carbonate, sulphates, bicarbonate, cations (Na+, K+, Ca++ and Mg++) and PAR.展开更多
文摘Paleo and recent earthquakes have been recorded in Wadi Hagul area and its environs, which have left behind geologic structures of deformation preserved in exposed sedimentary rocks. To evaluate such deformation and surface break, different techniques and data types are used compromising image processing techniques, Geographic Information Systems (GIS), seismicity data, as well as, field investigation. The field investigation clarified that the study area is enriched with soft-sediment deformation structures encompassing two types of geologic structures;brittle and viscoplastic structures. The analysis of the various types of data elucidate that, the earthquakes of Wadi Hagul are frequently distributed at an average depth ranging from (1 to 35 km) within the top of the Earth’s crust which are mainly controlled by existing Hagul fault zone. The study gives new insight for a better understanding of the seismic activity in the study area which helps in the seismic hazard
文摘The present study provides a vegetation analysis and species distribution at 50 sites, emphasizing the environmental factors that affect species distribution. A total of 74 plant species belonging to 67 genera and related to 23 families of vascular plants are recorded. Asteraceae, Poaceae, Chenopodiaceae, Brassicaceae, Fabaceae and Zygophyllaceae are the largest families, and therophytes (41.89) and chamaephytes (24.32%) are the most frequent, indicating a typical desert life-form spectrum. Chorological analysis revealed that 25 of the studied species were Mediterranean taxa, Saharo-Sindian chorotypes, either pure or penetrated into other regions, comprised 47 species. After application of the TWINSPAN and DCA programs, 4 vegetation groups (A-D) were identified, groups A and B were dominated by Achillea santolina, group C was codominated by Zygophyllm coccinum and Launaea spinosa and group D was dominated by Leptadenia pyrotechnica. Groups A and B may represent the vegetation types of the Western Mediterranean coast of Egypt, while groups C and D may represent the Wadi Hagul. The linear correlation of soil variables with the importance values of some dominant species and the application of Canonical Correspondence Analysis (CCA-biplot) indicates significant associations between the floristic composition of the studied area and the edaphic factors such as electrical conductivity, pH, calcium carbonate, sulphates, bicarbonate, cations (Na+, K+, Ca++ and Mg++) and PAR.