4275

4046

كارشناسي ارشد

خاكشناسي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1387

داوزده، 116، [II]ص.: مصور، جدول، نمودار

ص. ع. به: فارسي وانگليسي

حسين خادمي، مجيد افيوني

احمد، جلاليان

23/07/1387

جهانگير عابدي، مهران شيرواني

مهندسي كشاورزي

ID4046

به فارسي وانگليسي: قابل رويت در نسخه ديجيتال

AbstractThe industrial agricultural and urban activities have caused the pollution of heavymetals in soil that could also increase the concentration of these metals in the foodchain One of the most well known environmental pollutants is heavy metals whichhave noticeably increased recently Identification of the kind and the source of heavymetals is of pivotal importance As one of the biggest industrial cities in Iran Isfahanis exposed to contamination by heavy metals In previous investigations a greatportion of heavy metals concentration found in the soil was attributed to humaninduced pollution The main objective of this investigation was to distinguish heavymetals with anthropogenic source from the background concentration of these metalsoriginated from the parent materials in important landforms around the city ofIsfahan Three soil profiles each of them 2 m deep were investigated in eachlandform Three different extraction methods were used and the concentration ofselected heavy metals including lead cadmium zinc copper nickel and cobalt weredetermined by an atomic absorption spectrometer The results showed that except forlead and zinc the increase in heavy metals concentration is negligible and the currentconcentration of heavy metals at the depth of 2 m in studied soils is not very muchdifferent from that of the surface soil Also heavy metals contents in differentmethods are less than the threshold values of the heavy metals reported in differentcountries and only an increase in heavy metals concentration of surface soil isdetectable The differences in heavy metals concentration among landforms implydifferences among parent materials and the lithologically derived heavy metals insoils Sequential extraction results showed that a great portion of heavy metals is inthe residual fraction of the soil which cannot be at attributed to human activities Astrong relationship between the quantity of heavy metals and the content of CaCO3 EC and clay in the soils shows the great influence of these factors in controlling theconcentration of these metals in the soils studied Due to the precipitation andadsorption of heavy metals in calcareous soils of dry regions it can be concluded thatalthough the high amount of carbonates creates many problems for plant nutrition butit limits the mobility of pollutants such as heavy metals in soil and consequentlyreduces the risk of these compounds entering the human food chain

حسين خادمي، مجيد افيوني

احمد، جلاليان

جهانگير عابدي، مهران شيرواني