بررسي تغييرات مكاني فلورايد در خاك و آب هاي زيرزميني بخشي از اراضي استان مركزي

چكيده انگليسي :

Spatial Variability of Fluoride in Soil and Groundwater in Some Areas of Province Markazy Maryam mohseni Sajadi maryam@yahoo com 2009 2 30 Department of Soil Science Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiDr M Afyuni Afyuni@cc iut ac irDr H Khademi Hkhademi@cc iut ac irAbstractFluoride F is an essential element for some animals having positive impact on their growth rate ateven low levels This element reduces the solubility of tooth enamel under acidic conditions Concentration of fluoride higher than threshold level is harmful for humans and animals In most aridand semiarid regions groundwater is the main source of drinking and agricultural use The objective ofthis study was to determine temporal and spatial variability of fluoride in groundwater in agriculturaland industrial regions in a selected area in Markazi Province Arak Plain is located in an arid tosemiarid region in Markazi Province where the use of groundwater has become very important due tothe drought crisis in recent years The study region with an area of about 25 km2 is located in the northand the west of Arak city Water samples were randomly collected from wells during autumn andspring seasons Also 30 composite surface soil samples 0 10 cm were randomly taken About 80water samples were taken from wells in fall and 92 samples in spring Soil pH Electrical conductivity ECe and soil texture were measured Fluoride in soil solution and water samples was measured by IonSelective Electrode ISE The groundwater sampling location was determined using a GPA and landuse of each sampling location was recorded Water samples were analyzed for F NO3 EC pH Cl K Na Ca2 Mg2 SO42 The Fluoride concentration was mapped using Surfer computer programand kriging technique Omnidirectional variograms were prepared for soil and groundwater fluorideconcentration Spherical model was the best model to describe spatial variability of most parameters Mean square estimation error MSEE mean estimation error MEE and correlation coefficient wereused to determine validation of the variograms The results indicated that fluoride concentration in soilwas higher in industrial areas as compared to that in agricultural soils The difference in fluorideconcentration in soils of industrial and agricultural areas was statistically significant Average fluorideconcentration in groundwater samples during two seasons ranged from 0 03 to 0 53 mg l which isbelow the standard level 1 5 mg l The fluoride concentration was assessed to be suitable forirrigation and deficient for drinking The concentration of fluoride was not significantly differentamong different land uses However the concentration of fluoride in groundwater samples wassignificantly different between two sampling periods A significant correlation was obtained betweenthe concentration of fluoride in soil solution and soil calcium carbonates and pH Also fluoride inwater samples was highly correlated with Ca2 Mg2 SO42 pH HCO3 The results also showed thatthe spatial variability of fluoride in groundwater during two seasons follow almost the same pattern asCa2 pH and SAR and agricultural activity can effect the F concentration in groundwater Calciumconcentration seems to have adversely influenced the concentration of fluoride in groundwater andrising SAR and pH increase solubility of Flouride minerals Key Words Fluoride soil groundwater Markazi Province

محسني سجادي، مريم

بررسي تغييرات مكاني فلورايد در خاك و آب هاي زيرزميني بخشي از اراضي استان مركزي

زمين آمار , كريجينگ