Biomonitoring of the Urban Environment of Kielce and Olsztyn (Poland) Based on Studies of Total and Bioavailable Lead Content in Soils and Common Dandelion (Taraxacum officinale agg.)

Abstract

Kielce and Olsztyn are two different urban ecosystems. They differ from each other in terms of geological and climatic conditions, as well as spatial development and industrial past. The aim of this article is to assess and compare the degree of lead contamination of the natural environment in both cities based on the conducted tests of soils, as well as a common dandelion’s roots and leaves. For this study’s purpose, 60 samples of soils and common dandelion’s roots and leaves were collected in each city, according to four land-use types, namely industrial areas, urban green areas, urban allotment gardens, and urban forests. Basic physico-chemical properties and concentrations of lead, i.e., total content and bioavailable content were determined in the soils, using speciation analysis. Lead concentrations in the roots and leaves of common dandelion were, in turn, determined using the ICP-OES method. By using kriging models, spots with excessive lead concentrations differing from the geochemical background were identified in each city. The number of spots was comparable for both cities; however, the values for this metal differed significantly. No relationship has been found between land-use types and concentrations of lead in soils and common dandelions. The results of the study, as well as statistical and spatial analyses show that this species may be recommended as an indicator for biomonitoring of urban environments.