Showing 2 results for Hamadan Province
M. Arabi, A. Soffianian , M. Tarkesh Esfahani,
Volume 17, Issue 63 (6-2013)
Abstract
Physicochemical characteristics of soil, land cover/use and human activities have effects on heavy metals distribution. In this study, we applied Classification and Regression Tree model (CART) to predict the spatial distribution of zinc in surface soil of Hamadan province under Geographic Information System environment. Two approaches were used to build the model. In the first approach, 10% of total data were randomly selected as test data and residual data were used for building model. In the second approach, all data were used to build and evaluate the CART model. Determination coefficient (R2) and Mean Square Error (MSE) were applied to estimate the accuracy of model. Final model included 51 nodes and 26 terminal nodes (leaf). Calcium carbonate, slope, sand, silt and land use/cover were determined by the CART model to predict spatial distribution of Zn as the most important independent variables. The regions of western Hamadan province had the highest concentration of Zn whereas the lowest concentration of Zn occurred in the regions of northern Hamadan province. The results indicate good accuracy of CART model using R2 and MSE indices.
M. Barzin, H. Kheirabadi, M. Afyuni,
Volume 19, Issue 72 (8-2015)
Abstract
Soil pollution and accumulation of heavy metals in soils and crops are the most important bioenvironmental problems that threaten the life of plants, animals and humans. This study was conducted to explore contamination of heavy metals in soils of Hamadan province. A total of 286 composite surface soil samples (0-20 cm) were collected thoroughout the province. After preparation of the samples, the total contents of Zn, Pb, Cu, and Ni in soil samples were extracted using HNO3. Total contents of heavy metals were measured by ICP. Contamination factor results showed that most samples were moderately polluted and contamination factor for lead was highly polluted. Interpolated distribution map of contamination factors (CF) and pollution load index (PLI) of the heavy metals were prepared using GIS. The overlap of CF and PLI maps with geology and land use maps indicated that the concentrations of Ni, Pb, Zn, and Cu have been controlled by natural factors such as parent material, but agricultural activities according to excessive consumption of animal manure and chemical fertilizers can increase most of these elements in soil.