Multiscale analysis of heavy metal contents in Spanish agricultural topsoils

Abstract

This study characterized and mapped the spatial variability patterns of seven topsoil heavy metals (Cr, Ni, Pb, Cu, Zn, Hg and Cd) within the Ebro river basin (9.3 million ha) by Multivariate Factorial Kriging. The variograms and cross-variograms of heavy metal concentrations showed the presence of multiscale variation that was modeled using three variogram models with ranges of 20 km (short-range), 100 km (medium-range) and 225 km (long-range). Our results indicate that the heavy metal concentration is influenced by bedrock composition and dynamics at all the spatial scales, while human activities have a notorious effect only at the short-and medium-range scale of variation. Sources of Cu, Pb and Zn (and secondary Cd) are associated with agricultural practices (at the short-range scale of variation), whereas Hg variation at the short-and medium-range scale of variation is related to atmospheric deposition.

Distribution and Risk Assessment of Heavy Metals in Soils from a Typical Pb-Zn Mining Area

“…Numerous investigations have focused on the total heavy metal concentrations in Pb-Zn mining areas [15][16][17][18][19][20]. However, more comprehensive investigations including spatial variation, vertical distribution, and risk assessment of heavy metals in soil from the abandoned Pb-Zn mining area were rarely documented.…”

Watershed-scale assessment of arsenic and metal contamination in the surface soils surrounding Miyun Reservoir, Beijing, China

“…Comparing the range of As and metals, it was found that Cd and Pb have longer effective ranges than As and the other metals, which indicates that Cd and Pb have better spatial structure and less variation caused by extrinsic factors. Human activities have effects on only short and medium-range scales of variation (Rodríguez Martín et al, 2008). In this study, semivariograms of Cr, Cu and Zn are dominated by short-range structure, and the semivariogram of As and Ni are of medium-range variation.…”

“…The significant positive correlation between Cd, Cu, Zn and Ni is consistent with a common source for these metals. Associations among these metals can be indicative of sources due to human activities or geogenic and pedogenic characteristics (Facchinelli et al, 2001;Rodríguez Martín et al, 2008). As and Pb were significantly negative correlated to Cd, Cu, Zn and Ni.…”

Influence of irrigation on the occurrence of organic and inorganic pollutants in soil, water and sediments of a Spanish agrarian basin (Lerma)

“…Pb would originate principally from the gases emitted by vehicles) or natural causes (Facchinelli et al, 2001;Nicholson et al, 2003;Micó et al, 2006;Rodríguez et al, 2008;Sheppard et al, 2009).…”