7226

6732

كارشناسي ارشد

خاكشناسي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1391

چهارده، 113ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

شمس ا... ايوبي، محمدرضا عابدي

حسين خادمي

15/8/91

محمدعلي حاج عباسي، سعيد اسلاميان

1396/09/20

كتابنامه

كشاورزي

مهندسي كشاورزي

ID6732

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Effects of Land Use and Land Form Position on Soil Magnetic Susceptibility and the Rate of Erosion and or Deposition Using Cs 137 Technique in Fereidounshahr County Mohammad Reza Rahimi Ashjerdi Reza rahimi8599@ yahoo com 2012 9 1 Department of Soil Science Isfahan University of Technology Isfahan 84156 83111 Iran Language FarsiDegree M ScDr S Ayoubi Ayoubi@cc iut ac irDr M Abdi r abdi@phys ui ac irAbstractSoil erosion and sediment deposition represent serious problem in the word especially in hilly regionswith undulating topography Several techniques have been developed and used to measure soil erosionand deposition throughout the world Use of nuclear techniques in erosion monitoring and especiallyfor quantification of soil loss has offered a fast and economical tool to estimate erosion rate Cesium 137 is an artificial radionuclide with a high gamma radiation and half life of 30 2 years which wasreleased into the environment as a result of nuclear weapons tests primarily during the 1950 1970 Cesium 137 fallout reaches the earth s surface mostly as a result of precipitation and is strongly andrapidly adsorbed by fine soil colloidal particles such as clay minerals and organic matter in the topsoil Chemical or biological removal of Cs 137 from soil particles is limited and it is assumed that onlyphysical processes moving soil particles such as soil erosion and tillage practice are involved in the Cs 137 transport Magnetic techniques provide a rapid accurate non destructive and are relatively easyway been used to study soil erosion and trace topsoil movement on a hill slope In the Feridounshahrregion of Isfahan province soil erosion rate have increased dramatically over natural rates as a result ofhuman activities Therefore the objective of this study to evaluate the efficacy of magneticmeasurements for assessing soil redistribution by comparing with Cs 137 technique results in naturalpasture and cultivated soils Determining of soil redistribution rate was the other goal of this research The selected study area was located at hilly region with pasture and cultivation land use ofFeridounshahr Isfahan province in west of Iran Based upon the landform features summit shoulder back and foot slope and in 24 point from three depth 0 10 10 20 20 30 cm one hundred sampleswere collected in an area of 15 15 cm Soil samples were air dried and sieved using a 2 mm sieve Soilsamples 500 g were then placed in Marinelli beakers and sealed for Cs 137 analysis by gamma rayspectroscopy In this study a set of environmental magnetic parameters including magneticsusceptibility at low frequency lf and magnetic susceptibility at high frequency lh were measured Magnetic susceptibility was measured at low frequency 0 46 kHz lf and high frequency 4 6 kHz using a Bartington MS2 dual frequency sensor The results of correlation analysis showed that amongof all physico chemical and magnetic properties the magnetic susceptibility at low frequency r 0 83 in the pasture land and magnetic susceptibility at high frequency r 0 89 in thecultivated land had the highest correlation with Cs 137 inventory Throughout the multivariateregression analysis in the pasture land magnetic susceptibility at low frequency r 0 68 and thecultivated land magnetic susceptibility at high frequency r 0 79 were introduced as independentvariables for regression models developed in pasture and cultivated land respectively The resultsimplied that the use of magnetic susceptibility solely could explain all the variability of soil

شمس ا... ايوبي، محمدرضا عابدي

حسين خادمي

محمدعلي حاج عباسي، سعيد اسلاميان