M Shahraki; M.H Mahmudy Gharaie; R Moussavi-Harami; A Ahmadi
Abstract
In this research the catchment of the Sarbaz river, SE Iran, has been studied to determine sediment provenance and its possible pollution potential. 30 sediment samples collected from the riverbed were analyzed for major and trace elements, using combined XRF and AAS methods. Based on major and trace ...
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In this research the catchment of the Sarbaz river, SE Iran, has been studied to determine sediment provenance and its possible pollution potential. 30 sediment samples collected from the riverbed were analyzed for major and trace elements, using combined XRF and AAS methods. Based on major and trace element data and identification charts the sediments are identified to be of litharenite composition. Quartz-rich sedimentary and intermediate igneous origin and island arc tectonic setting is proposed for the sediments, mainly inferred from discrimination diagrams. Regarding the hazardous potential of metals and metalloids, As, Cd, Co, Cr, Cu, Fe, Mn, Hg, Ni, Pb, Se, V and Zn were studied from 30 locations. Pb, Cd and As concentrations measured respectively in 7, 10 and 20 locations are more than concentrations of the same elements in the world riverbeds. In this research, the polluted sediments were evaluated using the geo-accumulation index (Igeo). Based on this index, Cd, Pb, Zn and Cu show some degrees of pollution, while other elements are evaluated to be less pollutant. Statistic analysis show strong correlation between studied elements. Volcanic activity in north of the Makran zone can readily justify the common origin of the contaminants in the catchment of the Sarbaz river. Chromium is most probably originated from the nearby Makran ophiolites. It is concluded that geological factors have mainly been the controlling factors for the sediment pollution in the Sarbaz catchment.
N Hashemi; A.R Ashouri; M Aliabadian; M.H Mahmoudi Gharaie
Abstract
Paleozoology of Yafteh and Kani Mikaiel caves in center and northwest of Zagros Mountains led to the identification of small mammals' assemblage. Taxonomic determination revealed inclusion of four orders of small mammals including: order Rodentia with families of Muridea, Cricetidae, Calomyscidae, ...
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Paleozoology of Yafteh and Kani Mikaiel caves in center and northwest of Zagros Mountains led to the identification of small mammals' assemblage. Taxonomic determination revealed inclusion of four orders of small mammals including: order Rodentia with families of Muridea, Cricetidae, Calomyscidae, Dipodidae; order Lagomorpha with two families of Ochotonidae and Leporidae; order Soricomorpha with family Talpidae, and order Carnivores with family Mustelidae. These remains were recovered after systematic excavation in these caves. Radiocarbon analysis of these remains showed the oldest sample belonged to Yafteh cave with 35,000 BP. and Pleistocene period, whereas, Kani Mikaiel cave covered the periods from lat Pleistocene (19,000 BP.) to Holocene (17, 00 BP.). Geochronology analysis of Kani Mikaiel sediments showed that the lower layers of this cave belonged to the last glacial age in Pleistocene which gradually has been replaced by the warm weather in Holocene period. With continuing of this weathering varying, faunal spectrum of Pleistocene and Holocene periods has been migrated in cold and warm phases or more spread. The aim of this research, are the study of small mammal remains of Yafteh and Kani Mikaiel caves in center and northwest of Zagros mountains and the research about the study of paleobiodiversity, paleoenvironment conditions and the evolution of microvertebrate on the Iranian plateau.
F Behravesh; M.H Mahmudy Gharaie; F Ghassemzadeh; S Avaz Moghaddam
Abstract
Traffic dust often contains high concentrations of heavy metals and can influence on environment and human health. In this study, we tried to measure heavy metals in street dusts and soil in the city of Mashhad and sample collections were carried out at the time and location of high traffic. For the ...
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Traffic dust often contains high concentrations of heavy metals and can influence on environment and human health. In this study, we tried to measure heavy metals in street dusts and soil in the city of Mashhad and sample collections were carried out at the time and location of high traffic. For the purpose of this study, twenty three samples were collected from three main paths that cover the entire city and total concentrations of five heavy metals (Ni, Zn, Pb, Cr, and Cu) were measured. The index of geo-accumulation (Igeo), Pollution index (PI) and integrated pollution index (IPI) were also calculated for the contamination levels of the metals in the city of Mashhad,. The pollution index represent that all samples are highly polluted by Pb (3.688-74.16) and most of the samples are highly polluted by Zn (1.484-7.23). However, Cu (0.678-1.945) and Ni show medium level of pollution in the samples (1.01-1.935). Chromium in all samples show low levels of contamination (0.246-0.772). Possible sources of the pollutants were assessed using Pearson correlation and principal components analysis. The results of this analysis show high concentrations of metals such as lead, copper, zinc and nickel in the soil samples as compared to UCC (Upper Continental Crust). There is a positive correlation between heavy metals of zinc and copper as well as lead and zinc, which indicate the source of these metals, can be fuels as well as powder of shoe brake of vehicles. The results of the sequential extraction procedure also imply that the elements of Ni, Zn and Pb has occurred in unstable phases (F1+F2+F3+F4), indicating their human origin. But the elements such as Cr and Cu are mainly on stable phases (F5), which represents natural origin for these two elements.
