Enrichment of Iron and Manganese in Zayanderoud River
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Recent Advances in Applied & Biomedical Informatics and Computational Engineering in Systems Applications Enrichment of Iron and Manganese in Zayanderoud river sediments (Iran) JAVAD TABATABAEI Department of mining and petroleum ,Meymeh branch, Islamic Azad university, Meymeh,Iran [email protected] Abstract Zayanderud River, located in Isfahan Province with a length of about 420 km flowing from west to east, is one of the most important rivers of Iran. The river is very important because of its various applications of its water. However, many heavy industries, including Zovb-e-ahan Steel Company, Foolad Mobarakeh Steel Company, Polyacryl and other chemical plants as well as several power plants, refineries, military facilities, etc. discharge their wastewater into the river. In order to study the motion changes of the potentially poisonous elements of Iron and manganese and their effective factors in Zayanderoud river sediments, samples were taken from cross-sectional area of each of 12 sampling stations ( up stream to down stream), and then examined using an ICP-MS method (Inductive Coupled Plasma - Mass Spectrometry) . The results from the analysis of fine grain sediments indicate a high concentrations of Fe and Mn in several stations. The separation of human factors from natural ones was done by comparing Mn and Fe concentrations at Zamankhan bridge station ( as the reference sample ) with those of the other sampling stations by obtaining the enrichment coefficient. These results reveal that EF measured for elements such as Mn and Fe is high in samples and Geoaccumulation index shows that sediments of Zayanderoud river are little contaminated for these elements. Key words: Heavy metal, Enrichment factor, Zayanderoud river, Sediments 1 INTRODUCTION decompose heavy metals [14,15,24]. Hence, such pollutants usually form stable compounds and aggregates in the nature [3, 17, 20, 21]. Pollution of earth’s ecosystems by heavy In a river system, metals are distributed metals is a global problem. Due to population between solution phase (water column and water growth and increasing need for resources such as between sediment particles), solid phase (suspended water, food and energy, dangers associated with this and precipitated) and aquatic plants and animals. problem seem to be increasing every day. Moreover, metals consistently change phase and Because of absorption of pollutants through such changes vary with the environment [26]. breathing, eating, , drinking water and their transfer through food chain, pollutions can have serious effects on health. They, for example, may cause 2 MATERIALS AND memory disabilities, disabilities of various body METHODS organs, cancer, etc [9,10,18,22,23,25]. Polluting sediments in rivers’ basins may 2.1 STUDY SITE cause increasing pollution in downstream aquatic ecosystems. Zayanderud Basin is located in the central Water plays a major role in geochemical and plateau of Iran, comprising of a vast area. Its area is biological processes and is usually considered the about 41,550 square kilometers, 40%, 59% and 1% main carrier of pollutants [27]. Many types of of which is mountainous, foothill and swamp, pollutants do exist, each type of which pollutes respectively [12]. various environments. Heavy metals are considered Zayanderud, flowing from west to east, is the one of the most important water pollutants which not longest river of Iran’s plateau which passes through only pollute surface and ground water resources, but Esfahan City, with a length of about 420 kilometers. also can be absorbed by the soil and sediments It starts in Zardkuh Mountains and dries up in through cation exchange mechanism. As opposed to Gavkhuni Swamp (Fig. 1). most organic pollutants, living species can not ISBN: 978-1-61804-028-2 42 Recent Advances in Applied & Biomedical Informatics and Computational Engineering in Systems Applications The study area is located between Isfahan and could reasonably be polluted. The locations and Baghbahadoran and is part of zayanderoud basin, names of the stations, shown in Fig. 2, are ordered This Basin is located between 31o 15′N and from upstream to downstream. o In each of the twelve stations, a sample of 34 45′N . about 2 kilograms was taken from surface sediments According to above information, Zayanderud (located in sediment-water contact area). A plastic Basin has a variety of climates and shovel was used for sediment sampling. Then, weathers. There is a cold and mountainous sediments were put in polyethylene containers. It climate in the upper parts and a hot, arid should be noted that the same set of stations were and Mediterranean climate in the lower parts. used for water and sediment sampling. Precipitations occur in early fall until mid spring. 0.2 gram of sediment sample was put into The dry season is from mid spring to early fall. special Teflon container. 5 ml of nitric acid 65%, 2 Zayanderud bed in mountainous area is ml of hydrofluoric acid 48% and 1 ml of covered by coarse particle sediments such as cobble, hydrochloric acid 37% was added to the sample for pebble, granule and sand. A good part of flood plain digestion. Container was sealed and heated. and low-slope banks of the river are used for Digestion process is a multi-step process; in each agricultural applications. In eastern parts of the step, power, pressure and time were increased. region, lower slope causes the size of bed sediments to reduce so that final parts of the region are covered 2.3 ANALYSIS by silt and clay. Type and composition of geological We used ICP-MS (Inductive Coupled Plasma formations as well as tectonic affect the - Mass Spectrometry) instrument equipped with concentration of potentially toxic elements [7]. CCD detectors (V10ES model, Varian Inc.) to Hence, this section examines geological detect and measure heavy metal content in the characteristics of Zayanderud basin. samples. All of samples analysis in LABVEST From the first to the fifth station (Zamankhan laboratory ( Austria). Bridge to Kalleh Bridge), river bed is composed of In order to evaluate river pollution and pre-cambrian metamorphic rocks such as Gneiss, determine concentration and toxicity of heavy Amphibolite and Schist. In Cham aseman station, metals, reliable international standards need to be river bed is composed of Shale, Sandstone and used [5]. The standard developed and recommended Shemshak formation Mudstones (Jurassic) layers. by Kabata Pendias and Mukhrejee [13] is one of the River bed in Zarinshahr station is characterized by most complete ones of its own that establishes an Cretaceous Dolomite and Dolomitic Limestone allowed range for each element found in water, layers. In other stations, river bed is composed of sediment and rock studies (Tab. 1). alluvial terraces and new low foothill alluvial fans . This standard is used to evaluate pollution concerning each element in the basin of the studied 2. 2 SAMPLING river . Twelve stations were determined for 2.4 Geochemical Background Concentration sampling based on primary studies and field observations and by considering several parameters Geochemical background concentration helps including climatic characteristics, distribution of us better understand environmental dangers of pollution sources, secondary distributaries which pollution levels calculated for water, air and join the mainstream, tectonic features, change in the sediments. In fact, natural concentration of heavy composition of the river floor, slope of the river metals should be distinguished from heavy metal bank, location of industries, municipal and industrial content discharged into the environment by human sewage and wastewater discharge into the river, activities . access to the site, possibility of conducting sampling In order to determine geochemical process and pick up samples from the middle of the background concentration, we may use unpolluted river . First station, Zamankhan Bridge, was used as or less-polluted samples. In the case of the study, we the reference (blank) sample because of its may use samples taken from upstream parts where unpolluted water. Other stations used for no pollution sources were observed. It seems that environmental sampling were located in areas which the sample taken in Zamankhan Bridge (Station 1) ISBN: 978-1-61804-028-2 43 Recent Advances in Applied & Biomedical Informatics and Computational Engineering in Systems Applications can serve as the blank(i.e.reference)sample. As it can be seen in Fig. 3 and 4, heavy Statistical analysis of this sample is provided in Tab. metals concentrations are highly variable. Highest 2. concentrations were observed post-ZOVB-E-AHAN According to Tab. 2, metals concentration in Co. Station (located just after ZOVB-E-AHAN co. some cases are equal to global average. However, drainage pipeline) as well as Bagh Bahadoran for all elements and in both water and sediment Station, Zarinshahr Station and Falavarjan Bridge samples, concentrations are below international Station. limit. For some elements such as Co, we found no In most cases, concentration variation is due reference value because its concentration was below to geochemical background concentration. LOD. While we recommend using reference values However, in some cases, such variations can be instead of global levels, both international standards attributed to geochemical reactions between water and reference values are plotted in the diagrams of and sediments, such as sedimentation and this study to allow easy comparison. absorption. In other words, sudden