جستجوی مقالات مرتبط با کلیدواژه "soil pollution" در نشریات گروه "علوم انسانی"

Soil is a major component of the biosphere that is exposed to pollutants such as heavy metals. Soil pollution by heavy metals is an important issue and heavy metals originate from the two main sources of natural resources and human inputs including mining, various industries, road transport, mineral and chemical fertilizers for agriculture, sewage sludge, and industrial wastes. Mining and mineral processing activities are the most important sources of potentially toxic elements entering the environment and pollute various parts of the environment (including water, soil, air, and vegetation sources). Along with population growth and industrial development, mining activities for metal extraction have also expanded and as a result, the environment around the mines has been more and more affected by metal pollutants. Kushk Pb-Zn mine has been manually worked since 1940 and mechanized since 1964 and is located in a condensing and processing plant next to the mine. Mining waste is located on the margin of the mine deposited and can be spread downstream by wind or water. Because so far few studies have been conducted on the level and extent of pollution of soil sources around the lead and zinc mine, so the present study aims to evaluate the concentration of heavy metals (Cd, Mn, Cu, Fe, Pb, and Zn) and the extent of pollution and their environmental hazards were assessed in the study area. Sampling was done in November 2018 and 102 soil samples were collected from the Kushk mine area and its surroundings. Sampling has been done inside and outside the mine up to a radius of about eight kilometers. The location of the samples was determined by the Latin square method. The Latin Square Method is an almost modern sampling method that is stratified or layered. Their concentration was measured using a German model atomic absorption spectrometer (Jena330). After reading the concentration by the atomic absorption spectrometer, the obtained data were analyzed by Excel and IBM SPSS Statistic 22 software. Also, to show the spatial distribution of pollution of different elements considered in the research, the IDW method was used to prepare the maps using Arc GIS 10.3 software. Also, soil pollution was assessed using the pollution factor (CF), enrichment factor (EF), and land accumulation index (Igeo). This study evaluated six heavy metals in 102 soil samples (Cd, Mn, Cu, Fe, Pb, and Zn) conducted in the Kushk Pb-Zn mine in Bafq. The concentration of the studied heavy metals was in the order of Zn > Pb > Mn > Fe > Cd > Cu and only three elements of cadmium, lead, and zinc were above the alert threshold. The highest amount of elements was present in the southern part of the mine and near the mineral tailings and downstream of the road and sometimes on the road and machine traffic. The results showed the distribution of lead and zinc elements in the margins of the mine, especially in the margins of mineral tailings and downstream of the road. The reasons for this can be considered as the effect of wind and the existence of seasonal waterways in the transfer of these elements due to human activities such as mining and transportation to the mentioned points. Lead and zinc are gallons, so the amount of lead in the soil can indicate the geological origin of the contamination. The concentrations of copper, iron, and manganese for the soil in the study area were below the warning threshold. The results of the pollution indices used (except the Nemro index) indicated that the area was either not polluted or had little pollution. The Nemro index indicated that all elements (except copper) were severely contaminated. The lead was the highest element in all indicators, which can be said to be due to the type of parent rock and the geology of the region. On the other hand, the results of multivariate statistical analysis of heavy metals showed that vehicle and geological activities were the most important sources of zinc, lead, and cadmium contamination. Iron, copper, and manganese were mainly controlled by geological sources and parent materials, and manganese concentrations can be affected by fertilizers and agricultural soils. Due to the fact that the soil of the study area was contaminated with other heavy metals in addition to lead and zinc, so the need for more research in the area to evaluate strategic plans for soil resource management is necessary.

Affected by the change of land-use pattern, soil pollution has become an important environmental issue in developed and developing countries.  Heavy element pollution, as a kind of soil pollutant, is really dangerous due to their high toxicity and persistence in the environment. In the current study, the extent of pollution to heavy elements in downstream area of southern waste landfill of Kermanshah city was investigated. In this research, 208 soil samples (from 0 to 20 cm depth), were collected with 50 meters distances systematically from downstream area of waste landfill. The spatial pattern of variables was investigated through calculating experimental variograms and fitted models using geostatistics.  The mean concentrations of Fe, Mn, Cu and Zn in downstream area of waste landfill are 4077, 943, 41.8 and 102 mgkg−1 respectively. The spherical model was recognized as the best model to describe the spatial variability of total heavy metals. Total content of Fe, Mn, Cu and Zn showed a strong spatial dependence. According to the ordinary kriging maps, the total concentration of elements in the central parts of the study area is less than the other parts. This is probably due to the lower slope of the central region and consequently the lower infiltration. The concentration of elements in the southeastern towards the northeast High slope of the area is the result of the adjacency to the waste landfill and also the higher steepness in this part. The findings indicated a long-term progressive trend soil pollution, thus it is necessary to halt latex infiltration either towards the soil or vertically ground water. The results showed a long-term progressive trend in soil pollution. Considering population growth, waste production rate, distance from the city center, and other factors determining the location of landfill, it is suggested to reconsider positioning waste landfill scientifically. Furthermore, some services such as waste separation in the source, waste recycling in the source, and composting would be inevitable.

Nowadays, environmental pollution with heavy metals has become a global issue. Heavy metals can enter the environment through human and natural resources. Soil can hold environmental pollution and these pollutants can be checked by chemical analysis. The purpose of this field survey is assessment of soil pollution by heavy metals around Ilam Cement factory. In this regard, a total of 20 soil samples taken in different directions and the concentration of Zinc, Cobalt, Manganese, Molybdenum, Cadmium, Copper, Lead, Chromium and Nickel in soil samples was measured using atomic absorption spectrometry. In order to better understand about distribution of heavy metals, Geoaccumulation Index, Contamination Factor, modified Contamination Degree, Pollution Load Index methods applied. Results showed that although the concentration of all of heavy metals in the study area is less than standard but the correlation coefficient (R2) of elements in different directions show that the highest correlation coefficient for elements is in the North West direction of study area which is in agreement with main winds direction in the region. So wind direction is effective in elements distribution and their concentration decreased with distance from the factory.

Being informed of spatial distribution of heavy metals concentrations in soil for environmental pollution monitoring and maintaining the quality of the environment is necessary. This study aimed to map the spatial distribution of heavy metal contamination concentration of Manganese، Copper، Zinc and Iron in Harris agricultural soils located in the province of East Azerbaijan done. For this purpose، using systematic random sampling of 370 surface soil samples were collected at a depth of zero to 30 cm، and the concentrations of all these metals were measured. In order to modeling the spatial variation of heavy metal concentrations in the soil، the ordinary kriging and radial basis functions were applied in ArcGIS. Among the various models of ordinary kriging and radial basis functions، the lowest RMSE and MAE values and very close to zero MBE and the highest correlation coefficient R as a criterion for evaluating the best way to model the spatial distribution of heavy metals were considered. Both methods have accuracy، but based on proper the evaluation criteria for metals، Magnesium and Copper، kriging method with exponential model، for Zinc، kriging method with spherical model and for iron، RBF method with Multi-quadric function was chosen. The map after choosing the best model for each of the elements، drawing and taking into account the standard of the Institute of Soil and Water Conservation، re-classifying the elements in four classes deficiency، sufficiency، and infection. Analysis of the spatial distribution maps of heavy metal contamination showed that most of the land was sufficient range for Magnesium; for Copper was found that about 92 percent had a high class and about 8 percent of the study area was contaminated; contamination for zinc and iron wasn’t found and respectively، about 96 and 80 percent were deficient.

Global experiences indicate that, physical development of the cities on the boundaries of land and coast has sparked numerous problems, one of which is Caspian Sea environmental issues. The cost caused by coastal soil and water pollution in Northern Iran has led to new challenges for the officials of the urban affairs on one hand and a researchable subject to provide scientific strategies for the researchers on the other hand. Climate change and global warming has led to the advancement of the water to the Caspian Sea coast. Furthermore, the cities inclination toward the sea has raised the environmental load to a worrying degree. Thus, the current descriptive-analytical study with regard to proposed hypotheses tries to re-identify the negative dimensions of the physical development of the coastal cities. The results show that the increasing inclination of the city toward the coast has provided severe environmental problems and that many of the coming problems in the region can be prevented by principled planning and considering the role of sustainable development

To evaluate the impacts of polluted soils on human health, it is important to understand the of soil particle size distribution. Polluted soil particles are considered as pollutants and their transportation by water and wind depends on particle size. Applying the of new techniques such as spectrophotometry and remote sensing which enhance feasibility and swift determination of soils pollution risk could be useful due to high costs of soil sampling and laboratory measurements. This research has been carried out to determine spatial distribution of zinc concentration in soil particle size classes using IRS-LISS III reflectance in Southern Isfahan city. There fore, 100 compound soil surface samples have been collected randomly through the area. The samples have been air - dried and soil particle size classes 250-500, 125-250, 75-125, 50-75 and <50 μm have been determined, using appropriate sieves after dispersion the bulk soil samples by ultrasonic apparatus. Total Zn concentration has been measured using Atomic Absorption Spectrophotometer after wet digestion of samples in acid nitric. Results showed that concentration of Zn increases by decreasing soil particle size. Significant negative correlation coefficients have been found between Zn concentration in soil particle size classes and soil spectral reflectance in visible and near infrared bands of IRS-LISS III satellite. Stepwise multiple regression models have been used for estimating Zn concentration in soil particle classes through satellite data and spatial distribution of Zn concentration in soil particle size classes were mapped using stepwise multiple regression equations. Results showed possible estimation of Zn concentration to certain ranges of concentrations using multiple regression models and satellite data so that in size classes <2000, 50-75 and <50 μm concentrations lower than 400 mg kg-1, measured and estimated Zn concentrations are closed to 1:1 line. This is an indication of higher precision in estimating Zn-concentration at lower concentrations. The results also indicated increments of Zn concentration in all soil particle size classes by approaching to the mines.