Assessment of Soil Contamination Using Remote Sensing and GIS

In recent years, metal contamination has become a major source of soil pollution in Bangladesh because of intensive agriculture practices, mining, industrialization, pesticides, untreated sewage sludge and combustion by-products. This experiment aimed to assess metal contamination and cropping pattern in six upazilas of Bangladesh, using remote sensing and GIS technologies. A total of 30 locations were selected and 150 soil samples were analyzed for Cr, Co, Cu, Cd, Pb and Zn contents. The soils were contaminated by metals having concentrations (Cu: 101.70 ± 58.36 mg/kg; Co: 32.65 ± 11.34 mg/kg; Cu: 58.64 ± 10.07 mg/kg; Cd: 1.25 ± 0.09 mg/kg; Pb: 46.10 ± 25.76 mg/kg; Zn: 104.65 ± 45.74 mg/kg) which were varied significantly (p ≤ 0.05) across all study areas. Chromium concentration was significantly (p ≤ 0.05) higher in Tangail Sadar compared to that of Parbatipur, Ghatail, Laksam, Mollahat and Bagher Para. The maximum concentrations of Co and Cu were found in Parbatipur and Mollahat respectively, whereas Bagher Para had significantly (p ≤ 0.05) higher Cd levels. The coefficient of variation and spatial pattern for metals revealed that the contamination was related to the anthropogenic activities. The study indicated that Gaussiang model was the best fit for Pb; Exponential model was fit for electrical conductivity; Stable model was fit for Co, Cu, and Cd; Spherical model was fit for both Cr and Zn.