تفكيك رژيم هاي رطوبتي خاك با استفاده از تكنيك پذيرفتاري مغناطيسي و برخي خصوصيات خاك در خاك هاي لسي و شبه لسي بخشي از استان گلستان

چكيده انگليسي :

Discrimination of Soil Moisture Regimes Using Magnetic SusceptibilityTechnique and some Soil Properties in Selected Loess and Loess Like Soils of Golestan Province Morteza Valaei valayeimorteza@yahoo com January 12 2014 Department of Soil Science Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiShamsollah Ayoubi ayoubi@cc iut ac irAbstractAmong the soil forming factors climate plays a major role as well as topographic and climatic characteristicsaffected soil properties as parallel Soil moisture regime is one of the deterministic soil properties which play avital role in soil genesis and fertility Soil moisture regime also is important in soil classification soil survey land evaluation and management aspect Identification and differentiation of soil moisture regimes is verydifficult and time and cost consuming This study was conducted to differentiate soil moisture regimes usingmagnetic susceptibility techniques and some soil physical and chemical properties Our hypothesis was that soilphysical and chemical properties in combination of magnetic measures could discriminate the soil moistureregimes in the study area The study area included a climatic transect in the Golestan province north of Iran The parent material along transect is approximately similar including loess and loess derived parent material Inthe present study four soil moisture regimes comprising Aridic Aquic Xeric and Udic were selected alongtransect In this respect in each soil moisture regime twenty soil profiles were studied and total 100 profileswere drug and described The dominant soils in Aridic moisture regime were Aquisalids and Haplocalcidsbelonging to Aridisols an Entisols orders In the Udic moisture the greatest group was Argiudolls Afterpreparing the samples soil physicochemical properties were measured by standard approaches Iron componentsincluding crystalline amorphous and organic were extracted by citrate bicarbonate dithionite and amorphousiron oxide content was determined by oxalate ammonia Also magnetic parameters including magneticsusceptibility at low frequency lf high frequency hf SIRM saturation isothermal remanentmagnetization IRM100mT isothermal remanent magnetization at the field of 100 mT and IRM 100mT backfiledisothermal remanent magnetization at the field of 100 mT were measured The highest and lowest value ofmagnetic susceptibility at low frequency was attributed to Udic and Aquic moisture regime respectively Significant positive correlations were obtained between magnetic properties Positive significant correlationswere obtained between Fed Fed Feo with magnetic susceptibility at low frequency The ratio of Fed to FeOshowed negative correlation with magnetic susceptibility at low frequency The gypsum and electrical contentindicated negatively significant correlations with both of low and high frequencies magneticsusceptibility Among the soil properties calcium carbonate organic matter salinity and Fed clay content siltcontent showed significant correlations with magnetic measures The results showed that discriminate analysishad more accuracy than multiple regressions for discrimination of soil moisture regimes in the studied area Theresults of study revealed that magnetic measures could be applied as a powerful indicator for differentiation ofsoil moisture regimes The results of discriminate analysis verified that measures in control sections f profilesresulted powerful results as compared to measures in surface and subsurface horizons Although incorporationof soil physical and chemical with magnetic properties provided highest accuracy for soil moisture regimeprediction but using of magnetic measures with 80 accuracy and also for low cost and rapid measurement aresuggested in the study area for soil moisture regimes discrimination Key words Soil moisture regime magnetic susceptibility climate loess discriminate analysis

والائي، مرتضي

تفكيك رژيم هاي رطوبتي خاك با استفاده از تكنيك پذيرفتاري مغناطيسي و برخي خصوصيات خاك در خاك هاي لسي و شبه لسي بخشي از استان گلستان

اقليم , آناليز