The objective of this study was to quantify and assess for the first time the variability of total mercury in urban soils at a previous termEuropeannext term level, using a systematic sampling strategy and a common methodology. We report results from a comparison between soil samples from Aveiro (Portugal), Glasgow (Scotland), Ljubljana (Slovenia), Sevilla (Spain), Torino (Italy) and Uppsala (Sweden).
At least 25 sampling points (in about 4-5 ha) from a park in each previous termcitynext term were sampled at two depths (0-10 and 10-20 cm). Total mercury was determined by pyrolysis atomic absorption spectrometry with gold amalgamation. The quality of results was monitored using certified reference materials (BCR 142R and BCR 141R).
Measured total mercury contents varied from 0.015 to 6.3 mg kg− 1. The lowest median values were found in Aveiro, for both surface (0-10 cm) and sub-surface (10-20 cm) samples (0.055 and 0.054 mg kg− 1, respectively). The highest median mercury contents in soil samples were found in samples from Glasgow (1.2 and 1.3 mg kg− 1, for surface and sub-surface samples, respectively).
High variability of mercury concentrations was observed, both within each park and between previous termcities.next term This variability reflecting contributions from natural background, previous anthropogenic activities and differences in the ages of previous termcitiesnext term and land use, local environmental conditions as well as the influence of their location within the urban area. Short-range variability of mercury concentrations was found to be up to an order of magnitude over the distance of only a few 10 m.
- Urban soils
- Urban parks
- Environmental quality