Heru Hendrayana

Determination of Lead Contamination in Urban Soil, Yogyakarta City, Indonesia

Lead (Pb) is one of common heavy metal that has been shown to be very useful tracers of environmental pollution. The consequences of urbanization process can cause not only economic growth but also negatively impact on the quality of water and soil. Therefore the objective of this research is to know the potential contamination of lead in soil of urban area. The soil samples were conducted by batch leaching experiment. In surface soil, lead in soil of Pakem area varies from 2.01ppm to 5.13 ppm with average value of 3.02 ppm and Merapi area ranges from 1.84 ppm to 3.41ppm with average value of 2.42 ppm. In urban area, lead varies from 4.18 to 14.88 ppm with average of 9.93 ppm. Lead in urban soil is higher than Pakem and Merapi soil. The potential contamination of lead in urban soil is occurred with respect to urbanization and human activities. The value of lead is shown with the average of 3 ppm for Caturtunggal, Depok District, 6.53 ppm in Mantrijeron District and 9.82 ppm for Kotagede District in Yogyakarta city. The result of lead distribution in Kotagede District is the highest concentrated and it is followed by Mantrijeron District and Caturtunggal, Depok District.

Geochemical fractionation and risk assessment of copper in urban soil, Yogyakarta city, Indonesia

Copper (Cu) is one of the most pollutants that impact the soil of urban environment. Urbanization in Yogyakarta city with its human activities causes asoil contamination. The objective of this study was to determine the geochemical fraction of copper and the risk assessment in urban territory. The study area, Kotagede district, is located in the southeastern part of Yogyakarta Special Province, and it is the oldest urban area. The soil sampling was drilled by hand auger until 7 meters and sampled for each 1 m depth from the surface. Six steps of sequential extraction procedures were carried out to assess the geochemical fraction of copper and risk assessment of copper. The highest amount of copper was found in amorphous iron oxide with the average of 81.72%. Exchangeable of copper in the geochemical fraction was shown in anegligible amount. Because of high concentration copper in amorphous iron oxide fraction, copper seems to occur as poor mobilization, bioavailability, and low-risk assessment in the stud...