توزيع مكاني مس و روي در خاكهاي سطحي استان همدان با استفاده از مدل طبقه بندي و رگرسيون درختي

چكيده انگليسي :

Spatial Distribution of Cu and Zn in Surface Soils of Hamadan Province Using Classification and Regression Tree Model Mahnaz Arabi Email Address m arabi@in iut ac ir 03 09 2011 Department of Natural Resources Isfahan University of Technology Isfahan 84156 93111 IranDegree M Sc Language Persian Dr Alireza Soffianian Dr Mostafa Tarkesh Email Address soffianian@cc iut ac ir tarkesh es@yahoo comAbstract Among soil pollutants irresolvable heavy metals due to their toxicity accumulation properties andphysiological effect on living in low concentration are of most importance These elements due to theirlow mobility accumulated in soils in time Entering the food cycle their accumulation will threadhuman beings as well as animals The heavy metals accumulate mostly in the surface soil and thusexposure more to plant uptake and transport Thus studing concentration distribution for soil pollutionmonitoring of heavy metals is indispensible for maintaining the environment quality and should beconsidered at different levels of dicision making by researchers and managers The aim of study is theevaluation of spatial distribution of Cu and Zn in the surface soil of Hamadan Province withclassification and regression tree CART model and compare with kriging assessment of soilpollution of these metals using geoaccumulation index pollution index and integrated pollution index For this purpose the surface soil samples 0 20 cm were taken using systematic random samplingmethod and the concentration of heavy metals and some soil parameters such as pH EC thepercentage of organic matter calcium carbonate calcium sulfate sand silt and clay were analyzed Spatial distribution maps of these parameters were made by comparison of accuracy of differentkriging methods Radial Basis Function RBF and Inverse Distance Weight IDW by the MeanAbsolute Error MAE values Mean Bias Error MBE and Root Mean Square Error RMSE and thenprimary dataes were extracted for preparing CART model In addition needed dataes were extractedby elevation of sea level slop geographical aspect geology and land use maps of Hamadan Provinceand final CART model was prepared Nevertheless spatial distribution map of Cu was prepared byordinary kriging method and exponential model and spatial distribution map of Zn was prepared bysimple kriging method and gaussian model for assessment of kriging method accuracy compared withCART model The regions of western and northern Hamadan Province respectively had the highest andlowest concentration of Cu and Zn The most important factors to concentration of Cu following resultsof prepared model can indicate slope calcium sulfate and calcium carbonate elevation and percentageof organic matter and most important factors to concentration of Zn percentage of calcium carbonate slop sand silt and land use were determined The results indicate that accuracy of CART model ishigher than kriging method using coefficient of determination R2 and Mean Square Error MSE indices The assessment of soil contamination using geoaccumulation index IGEO based on thebackground of concentration in the study area classified the contamination as low to negligible in theregion According to the pollution index PI more than half of the samples had intermediatedpollution based on Cu and Zn According to the integrated pollution index more than 70 of thesamples classified the contamination as medium pollution based on these metals Due to consistencyof he areas with high concentrations of the elements with agriculture landuse the Integrated PollutionIndex IPI indicated that agriculture activities could also increase the concentration of these elementsin the soils Key words Hamadan Province Geographic Information Systems Environmental Factors Heavymetals Classification and Regression Tree Model

اعرابي، مهناز

توزيع مكاني مس و روي در خاكهاي سطحي استان همدان با استفاده از مدل طبقه بندي و رگرسيون درختي

سامانه اطلاعات جغرافيايي , فاكتورهاي زيست محيطي , فلزات سنگين