Scientists unearth clues to soil contamination by comparing old and new soil samples

Abstract

Oil contamination during the era of industrialization is a complex but important topic for those involved in land use planning and health assessment [ Feshbach , 1995]. One of the most direct ways to estimate the anthropogenic contamination of soil is to compare soil samples collected before the intensive industrialization period with modern samples taken from the same locations. Quantitative information about postindustrial trends in soil chemistry is usually derived from old measurements of the soil's chemical composition.The use of such old data, however, poses important limitations. First, in most cases, the sampling site locations were identified with the name of the closest administrative district [ Lindert et al. , 1996] or nearest village or town [ Sherbakov and Vaseneva , 1996], rather than the specific location of the sampling site. Because of significant natural variability in soil properties, a difference of only a kilometer yields pronounced differences in soil composition and structure. Other challenges arise from using different soil analysis methods. For instance, the 100‐year‐old measurement of soil humus by the so‐called “dry combustion” method can underestimate humus and organic carbon content by ∼40% [ Sherbakov and Vaseneva , 1996].