نشریه زمین شناسی محیط زیست
پیاپی 30 (بهار 1394)

The pollution of aquatic ecosystems by heavy metals is a global issue and one of the main problems in aquatic ecosystems, including wetlands. For this reason, examining the pollution in Amir-Kalayeh wetland was considered as the main goal of this study. In the current research, this wetland was studied in terms of the origin of the contamination, contamination factor, pollution load index, enrichment factor, and geo-accumulation index of elements to evaluate the distribution of heavy metals in the sediments of the area under study. For this purpose, 12 samples were taken from the surface sediments of the wetland from locations that represent the whole wetland and the concentrations of elements such as Al, Fe, Mg, P, As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V and Zn in the sediments were measured. Then, using statistical methods such as Pearson correlation coefficient, cluster analysis and factor analysis, the natural or anthropogenic origin of these elements were determined. According to the results, As, Cd, Mn, Mo, Ni, And Pb have contamination factors over one, which means they have contaminated the area. that is probably caused by agricultural pesticides and Amir-Kalayeh wetland, except for the pollution by agricultural fertilizers, is a fairly clean wetland, with no pollution from domestic and industrial wastes.

Damghan dam is made in 12 km northwest of the city of Damghan on the river of Cheshmehali. It plays an important role in the economic life of the region because of its multi-functionality: providing water supply for the region, and for agriculture in lowlands; generating power; pisciculture; and as a recreation resort. One of the most important issues in construction of dams is the environmental impact imposed on the area’s ecosystem during construction and exploitation process.. In this Research, environmental parameters are studied in the two phases of construction and exploitation impacts using descriptive, documentary and statistical Whetten Vray matrix and multivariate statistical methods by cluster analysis. Therefore, environmental parameters are identified and measured, a conclusion is drawn, and the measurements were converted into common scalar units.. The impacts of the dam construction on parameters such as surface water, groundwater, soil and morphology of the region are is studied based on our research and performing weighting on available data. Results show that the Damghan dam lake, despite its negative influences on water resources, plant and animal ecosystems, is considered to have positive effects on the region because it provides water supplies for the region and agriculture; improves the economic, social, and sanitary conditions; balances the climate; and gives beauty and recreational sites to the region.

The main objective of this study is to determine the possible sources and spatial distribution of some PTEs in surficel sediments of Pariz region in Kerman province by means of statistical multivariate analysis, enrichment factor and Geo-accumulation index. In the following survey, 8 PTEs “Cu, Pb, As, Mo, Cr, Co, Zn and Ni” from Pariz region have been analyzed using ICP-MS instrument in Geological Survey of Iran (GSI). The results of the analyses have been studied using Spearman correlation coefficient, Principal Component Analysis (PCA) and PTEs distribution map using Geo-accumulation index. Two main scenarios have been identified for pollution intensity and sources of these PTEs. The first scenario consists of Zn, Cr, Co and Ni elements which does not demonstrate obvious pollution patterns, originated mainly from Coloured Mélange and volcanic sediments. While Cu, Mo, As and Pb are classified in second group and cause high pollution in the region. The possible sources for the PTEs in the second group is probably Granodiorites and Dasites rocks and shales existed in the geological formation of in the study area. The substantial pollution of the second-group elements in the vicinity of Sar Cheshmeh Copper mine and Dareh Zar Gold mine demonstrate the anthropogenic source of these elements distribution.

Erosion is a natural process which is developing all around of the earth and it is important in changing surface of the earth. The purpose of this research is preparation of maps of sensitivity of rock to erosion, erosion intensity, rate of erosion and sediment yield of rock units in Abhar-rood watershed by using an experimental model of EPM in a GIS environment. Abhar-rood watershed basin with 189256.1 hectares is located in the southeast of the Zanjan. The study area shows a semiarid and Mediterranean climate with average annual rainfall of 344/5 mm. There are geological formations related to Paleozoic, Mesozoic and Cenozoic in this region. Kahar Formation (Pre-Cambrian) is the oldest and Quaternary alluvial deposits is the youngest deposits. The region is mainly consisted of sedimentary rocks. For better study of the area, it is divided into eleven subbasins. In this research, the factors affecting erosion and its forms and also rate of erosion was calculated and then erosion types map is prepared. Map of sediment yield ratio was prepared using Arc GIS software and intensity of sediment yield was calculated by experimental model of EPM in each subbasin. Subbasin A7 shows the minimum and subbasin A2 the maximum annual sediment yield in this basin. The specific sediment yield was estimated 8.81 in tons per hectare per year in this area. Calculation of EPM model shows that the erosion intensity is very sever in Abhar-rood basin. The A2 subbasin should be the first priority for soil conservation programs.

Sarcheshmeh Copper Mine is the largest porphyry deposit in the world and in this study heavy metal contamination is investigated. To determine concentrations of these elements, intact samples of soil, surface water and groundwater of the region have been sent to the laboratory for analysis. After determining the concentration of samples, the data are analyzed using Excel and ArcGIS. Using Kriging method, the variations of chosen elements’ concentration are interpolated and the maps and charts are drawn.. The results show that concentrations of copper, molybdenum, lead and cadmium in the soil of this region, on average, are respectively 235ppm, 13ppm, 65ppm and 7.1ppm which exceeded the limits and according to international standard, soil is unfavorable. The concentration of Aluminum, lead, molybdenum and cadmium in river water source on average, are respectively 0.73ppm, 0.8ppm, 1.32ppm and 0.42ppm; and in of groundwater on average are respectively 0.9ppm, 0.4ppm, 0.8ppm and 0.2ppm is. The comparison of concentration of these elements in surface and groundwater with global quality criteria standards indicates that the concentration of these elements according to different uses are not desirable. The analysis indicates an increase in the concentration of these elements in the southern part of the map area (mine), the source of the river downstream and adjacent to the mine fields to other parts of the region.

Though there are several alternatives to solid waste disposal, including the sanitary landfill method, the incineration method, the composting method and anaerobic digestion, but disposing of waste in a landfill is the most traditional method of disposal of solid wastes, and it is a common practice in most developed countries. Several techniques and methods have been used in a sanitary landfill site selection in the literature. In this paper three methods consist of a simple additive weighting method, fuzzy based method and Neuro - Fuzzy hybrid method has been used to landfill site selection in Lorestan province and the results of three methods have been compared to each other. The prepared maps by means of simple additive weighting and fuzzy methods have a correlation with the real condition of ground of 43 and 65 percent, respectively, whereas the Neuro - Fuzzy method map has a 55 percent correlation with field observation.

Lead and zinc mine of Larikhani is an abandoned mine which is located in the northern slopes of Alborz mountains in the south of Siahkal city of Gilan province. Geochemical and environmental characteristics of the host rocks indicate that the carbonate rocks were deposited during Cretaceous. The mineralization consists of pyrite, arsenopyrit, chalcopyrite, galena, sphalerite, colitis, plattnerite, cerusite, smithsonite, and iron hydroxides. The minerals can be seen as veins and veinlets which have filed the pore spaces. Galena, sphalerite and pyrite are primary and most frequent. Based on geochemical studies on the springs of hot water in the studied area, there is no indication of element anomalies. Geochemical studies show high concentrations of lead, zinc, cadmium and arsenic. The high concentration may results in contamination which is important for the animals living and feeding in the area. In this study, the environmental contamination of the abandoned lead-zinc mine was investigated.