6835

6377

كارشناسي ارشد

خاكشناسي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1390

چهارده، 109ص.: مصور، جدول، نمودار

ص.ع.به فارسي و انگليسي

حسين خادمي، شمس اله ايوبي

حسين شريعتمداري

19/4/91

فرشيد نوربخش، جهانگير عابدي

1396/09/14

كتابنامه

كشاورزي

مهندسي كشاورزي

ID6377

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Mapping of Total and Available Potassium in the Surface Soils of Fereidan District Hosseinali Soleimani E mail hosseinali soleimani@yahoo com Jan 25 2012 Isfahan University of Technology Isfahan 84156 83111 Iran Department of Soil ScienceDegree M Sc Language FarsiSupervisor Dr H Khademi E mail hkhademi@cc iut ac irSupervisor Dr S Ayoubi E mail ayoubi@cc iut ac irAbstractNutrient supply greatly affects the growth of plants Potassium K is an essential nutrient which isabsorbed by plants much more than phosphorus and as much as or even more than nitrogen Theobjective of this research was to map total and available K in the surface soils of Fereidan Isfahanregion Factors affecting the spatial variability of K including parent material land use and topographywere investigated The relationship between the total and available K and selected soil properties werealso studied A total of 165 surface soil samples 0 15 cm were taken from soils developed on 7different parent material in an area of 60000 ha The total and available K were determined using theexctuaetion method by NaOAC and acid digestion respectively Selected soil characteristics includingpH EC CEC organic matter carbonates and soil texture were also measured Besides mineralogicalanalysis was carried out on selected soils with different parent materials Results indicated that therewere statistical difference in both total and available K among the soils developed on different parentmaterials Soils formed on granite and limestone showed the highest and lowest level of the total K while those derived from old alluvium and the mixture of schist fine textured sandstone and marblehad the least and the maximum level of available k respectively Dryland and irrigated farms had themaximum and minimum amount of the total k respectively Besides gardens and rangeland had thehighest and lowest level of available k respectively The mean available K concentration in the soilsstudied was 354 3 mg kg 1 a value higher than the limiting threshold for most agricultural crops Available K level in a vast area of the study region varied from 241 to 400 mg kg 1 indicating that thesoils could well supply enough K for years About 27 6 of the study soils had an available K levelof less than 240 mg kg 1 requiring appropriate K fertilization management Only a small fraction of thetotal K in the soils is available to plants This is mainly due to the dominance of muscovite as aresistant mineral in the soils studied Among the soil properties studied the sand content waspositively correlated with the total K level where as the other soils characteristics showed an appositetrend Furthermore clay content organic matter and CEC were highly correlated with available k Mineralogical analysis indicated that kaolinite illite quartz and a small quantity of chlorite andvermiculite occur in the soils studied K bearing minerals mostly occur in the coarse sized particlesand the fine fractions have less K containing minerals Autocorrelation analysis shows that both thetotal and available K in the study soils are moderately spatial dependent Range of spatial dependencewas higher for available K as compared to the total k KeyWords Available potassium Total potassium Parent material Topography Spatialvariability

حسين خادمي، شمس اله ايوبي

حسين شريعتمداري

فرشيد نوربخش، جهانگير عابدي