Distribution of mercury in soil according to the geomorphological units of Vojvodina province

Establishing Hg background levels in various soils is problematic. The main problem is distinguishing human input (pollution) from natural Hg input. Geostatistical methods and Geographic Information System (GIS) mapping have been used in numerous studies to determine spatial distribution and behavior of heavy metals in soils and to identify their sources. A grid superimposed on Vojvodina land by means of a GIS tool (GIS ArcView 10) has divided land into 4x4 km units, each representing an area of 16 km 2 . Total number of 1,370 bulked soil samples were taken (0-30 cm depth) from agricultural land and analysed for total mercury content THg. The samples were analysed using Direct Mercury Analyzer DMA 80 Milestone. Quality control was carried out with IRMM BCR reference materials 143R. The aim of this study was to determine the total con- tent of Hg in agricultural soils, its spatial distributions in different parts of Vojvodina Province. It was indicated that the content of Hg coincides with main geomorphological units of Vojvodina Province. Hg spatial distribution indicated that most of Vojvodina Province area has geochemical origin of Hg. Average values of Hg concentrations for soils format- ted on different geomorphological units were: 0.031 for sandy area with dune fields, 0.048 for alluvial terraces, 0.055 for upper Pleistocene terraces, 0.058 for loess plateaus, 0.083 for mountains, and 0.092 mg kg-1 for alluvial plains