نشریه زمین شناسی محیط زیست
پیاپی 29 (زمستان 1393)

Heavy metal pollution of water sources due to discharge of factories into environment is the highest risk for human and environment health. Humans and animals by consuming vegetables and food staff washed with polluted water are at high risk. The quality of surface waters is a very sensitive issue. Sampling for watershed was carried out over 4 months (April, May, June and July) from 6 stations and quality parameters were determined. These parameters are: pb, Zn, Cu, Cd, Ni and Fe. Also the data were analyzed with standard methods and atomic absorption. Results showed that in April the highest average was that of pb (.0.54 mg/l) and the lowest cadmium (0.001 mg/l). In May, the highest average was related to pb (1.15mg/l) and the lowest its was Fe (0.013mg/l). In June the highest and lowest averages were Cu(.0.56 mg/l) and Fe (0 mg/l) respectively, while also in July they were Cd (0.018 mg/l) and Fe(0 mg/l). The River was polluted with heavy metals in some stations and water quality of this river does not matchwith standards. With physical, chemical and biological agent monitoring and also with control of water quality indexes in these stations, we observed wastewater and other pollution arrive river. Environmental effects of pollution are seen in different parts of the river.

In order to study the effect of hydrogeochemical parameters on arsenic contamination level, the surface and groundwater samples were examined in the Sefid Rud basin. Statistical analyses display medium correlation between physicochemical parameters (such as EC, BOD, TDS, COD) and abundance of arsenic in surface and groundwaters of the study area. As abundance shows indirect correlation with nitrate and Do in surface and groundwater samples. The highest As contamination levels were observed in Fakhrabad and Salkadeh during October and November. The multivariate statistical and graphical techniques were used to identify the sources of arsenic along the river basin. Hydrogeochemical parameters of surface and groundwater samples plus mineral assemblages and sedimentological characteristics of the quaternary alluvial were examined in the Sefid Rud basin where As concentration in the samples is highly variable in different places.The hydrogeochemical data suggest that the releasing of As into surface and groundwaters of the study area is controlled by complex processes including: 1) the dissolution of As from surface of Fe-oxyhydroxide minerals as the primary mechanism responsible for releasing As into surface and groundwaters, 2) weathering of minerals and rocks, 3) mineralogical composition of aquifer, 4) salt input (from evaporate deposits), 5) ion exchange processes (clay minerals in sedimentary rocks), 6) velocity and volume of groundwater flow, 7) precipitation and 8) anthropogenic activities.

Biogeochemical cycle begins with rock, so geology and geochemistry of rock and soil erosion play the most important role in the distribution and concentration of potentially toxic elements in each ecosystem. In this study, rock and soil samples from Gorveh, Bijar and Takab cities were analyzed using ICP-MS instrumental method. Geochemical analyses indicate high amounts of heavy metals such as As, Ni, Cd, Se and Co in soil and travertine samples, of which arsenic is prominent (>10000 ppm). XRD analysis revealed how heavy metals are present in the travertines of the area and by integrating mineralogical and geochemical results, the main reason for high concentration of As in these deposits was shown to be the presence of arsenic bearing minerals. The environmental indices including enrichment factor, contamination factor, pollution load index, potential ecological risk index were calculated and indicated that the majority of the samples are categorized as highly contaminated. Average arsenic concentration in rock and soil samples is 423 and 1089 (mg/kg) respectively. The main reason for such high heavy metals contents -especially arsenic- in the area is believed to be the existence of many hot springs representing waning stages of volcanic activity.

One of the serious environmental problems that could cause irreversible ecological and economic damage to the environment is organic pollutants. Contamination with organic pollutants is a very serious issue that is of interest to the general public because in some cases, it causes serious damages to the environment, soil and water as well. Polycyclic aromatic hydrocarbons which are abbreviated as PAHs are one of the major groups of organic substances soluble in water due to the geological conditions of the region. Various methods are used to clean up polluted aquatic environments among which the use of oil absorbent material to remove different kinds of contaminants, particularly petroleum compounds and its derivatives (Polycyclic aromatic hydrocarbons) is highly regarded. PAHs absorption by the bentonite and activated carbon is considered in this research. Then, PAHs distribution coefficient and the maximum absorption have been determined according to the results using Freundlich absorption isotherms, and Langmuir isotherm. Results show that the bentonite has a high potential for PAHs absorption. Distribution coefficient (kd) and the maximum absorption are 0.005 L/g and 0.157 mg/g.

Narigan area is located in Bafgh-Saghand metallogenic zone on Iran plateau. There are some anomaly radioactive elements which can penetrate into the soil, plant roots, plant textures and animal bodies. On the other hand, these anomaly radioactive elements can effect animals by emitting dangerous rays. During this research for environmental studies in Narigan area, after determining plants and animal viodeversity, 15 samples were chosen from plant bodies and the soil around them. Radioactive elements were measured by (HPGs) device. According to the analysis results, most of the samples contain large amounts of radioactive elements such as: Ra226, U, and Cs137and K40 which are a risk for environment of this area. Due to the studying of plants and soil samples, Astragalus can be used as geo botanical indicator for U and Th elements in this area.

Development of land in the area of natural resources and human threats to the environment from various sources is imported. This study aimed to compare the results of the Minnesota Pollution Control method Bushehr landfill site selection and environmental protection organizations in the GIS were studied. Methods Minnesota Pollution Control consists of two groups of factors. The first group of six playoff factor and the second group of seven secondary condition factor, failure to meet the six primary factor in eliminating the desired location. Environmental criteria are examined and the distance from surface water, airport, away from roads and highways, are wells, wetlands, and sensitive earthquake-prone areas, terrain, annual waste deep underground water, land use, erosion, cover Plant and primary and secondary factors were determined in Minnesota with the use of GIS. The results showed landfill in Bushehr current zoning and distance from the aqueduct and Jshmhhay most studied area in Minnesota inappropriate criteria in categories B, a secondary index. According to the Environmental Protection Agency, landfills% 43.75% 56.25 appropriate and inappropriate. This limiting factor, distance from surface water, exposure to wind, flood storage areas, making the area susceptible to earthquakes and low depth to groundwater from shallow wells due to proximity to the sea has a great impact. Classification erosion study area are inadequate landfill and erosion in the region is very high.

The ecological potential assessment of land as one of the guidelines for moving towards sustainable development is looking for assessing land latent capacity with standards and preplanned criteria. Identifying and assessing the ecological characteristics of each region are, guidelines for a development in tune with nature. And in this way, the nature itself clarifies acceptable developmental capacity. In this study, Dayer Nakhiloo national marine park which covers an area of 202.34 square kilometers in the East of Bushehr has been selected and after identification of environmental resources and map preparation by using multi criteria decision making methods and taking advantage of the geographical information system (GIS), overlaying maps, appropriate areas for intensive and extensive recreation were identified. Then, according to the economic development of the region and due to the sensitive and protected zones within the study area, final zoning was made. The results have shown about 21.47% of the area (43.3 square kilometers) is appropriate for protection and 67.52 percent (136.16 km2) is suitable for extensive recreation zone, besides about 11 percent (including 22.19 sq km) is dedicated to intensive recreations.