جستجوی مقالات مرتبط با کلیدواژه "heavy elements" در نشریات گروه "جغرافیا"

Water pollution has always been one of the environmental issues around the globe. Among the surface and underground waters, running water and rivers are constantly exposed to more pollution due to the crossing of different areas. The purpose of this study was to evaluate the water quality of Kor River in south of Iran and determine the source of contamination by different factories located nearby. Maternal sample in 2016 on 14 physical and chemical parameters, December 3, April and September). 29 stations completed. Principal Component Analysis (PCA) determined the most important parameters affecting water pollution, and WQI and HEI indices determined the contamination status of each site according to the permissible limits in the river water, and finally, using Karjing method. The spatial distribution of elements in adjacent factories was investigated. The results of the measurements using Principal Component Analysis (PCA) showed that PCA introduces 13 components. The average of the lowest WQI index at station 17 was 0.9 ± 5.0 with non-food quality and highest value at station 6 with mean 87.3 ± 2.0 with good drinking status. Results from HEI showed that stations 16 and 17 had the highest values of HEI index indicating the most polluted stations. The results of the HEI showed that the values of As, Cd were much higher than the permissible limit in drinking water. Finally, the results of heavy metal zoning maps using Kriging method showed that the highest concentration accumulation was related to the central and southern parts adjacent to the factories in the study area.

The aim of this study was to prepare a map of the distribution of lead and cadmium in the topsoils of parts of Qom province to the center of Qom city, with different agricultural, urban and industrial uses of barren in two total and absorbable forms. The spatial distribution of these elements in surface soils with different uses with an area of ​​1054 square kilometers was investigated. Sampling was performed at 209 points by networking the study area and the total and absorbable amount of lead and cadmium was determined using an atomic absorption spectrometer. All-round variograms of these elements were drawn by Variowin software. Due to the lack of a proper structure, no changes were made to the cadmium, kriging and mapping. Intermediation was performed by point kriging method with WinGslib software. MEE and MSEE were used to determine the accuracy of the estimates. The range of changes in total lead with a minimum of 9.6 and a maximum of 123.4 mg / kg is reported to be 113.8. In this study, the minimum and maximum total cadmium concentrations were 0.2 and 5.5, respectively. The average concentration of absorbable lead in the study area is 4.1 mg / kg with a minimum of 0.5 and a maximum of 34.8 mg / kg. Based on the lead distribution maps, it seems that the effective factor on the increasing trend of this element is the type of use. Lands with urban and industrial use had the highest amount of total and absorbable lead, which indicates the high potential of the area for pollution. Therefore, it is necessary to take the necessary management measures to prevent the occurrence of destructive environmental accidents.

Water is one of the most vital human needs. Chromium is one of the heavy metals that causes water pollution in different regions. The studied area is Joghatai Mountains and Davarzan, Khoshab, Joghatai, Joveyn and Sabzevar plains of Razavi Khorasan Province. This research has studied, analyzed water pollution with the element of chromium as well as the impact of lithology mountains Joghatai, on the quality of water in the region from the point of view of chromit. In this research, 13 samples were collected and tested by atomic spectrometer method.To check the amount of chromium present in them by comparing the findings with standard limits. The results of this study show that the amount of chromium in the selected water sources varies from 1.2 to 1.3 mg / L. Geochemical samples vary from 210 ppm to 4700 ppm. The lithology of the region especially the chromium mines has affected the quality of water but the density of faults and fans did not affect the amount of dissolved chromite. The effect of the slope of the geological layers is positive and the role of acidity in the pollution is poor. Finally, the amount of chromium in some samples is higher than the standard limit and should be considered by the custodians.