Assessment of Cadmium spatial distribution in surface soil in the vicinity of Shiraz refinery by geostatistical method

All forms of life on Earth are related to soil. Soil is the final environmental destination for material degradation. Considering the importance of soil contamination, evaluation of soil contamination by various industries seems to be necessary. Characteristics of spatial distribution of pollutants in contaminated soils are important factors to identify and eliminate pollution. Heavy metals are the most important environmental pollutants. This study was conducted to assess the environmental impact of Shiraz refinery.
40 composite soil samples were taken from a depth of 0-5 cm. Calcium carbonate percentage, electrical conductivity, pH and total and available Cd concentrations were measured. The data were analyzed and the spatial distribution maps were plotted using GS and ILWIS software.
Findings: In the study area, soile pH was in the range of neutral to alkaline and contained a high percentage of calcium carbonate and moderate salinity. The average concentrations of available and total cadmium are much higher than the standard limit and the highest concentration is observed in an area close to the refinery.
In general, it can be stated that refinery activity in the region, has led to increase of Cd concentration in the surface soil. This increase was in the range to cause Cd concentration to exceede the standard limit.