Urban soil quality deteriorates even with low heavy metal levels: An arthropod‐based multi‐indices approach

Abstract

Urban-induced habitat conversion drastically changes soil life in a variety of ways.Soil sealing, human disturbance, habitat fragmentation, industrial and vehicular pollution are the main causes of urban soil degradation. Soil arthropods, as one of the most abundant and diverse group of soil fauna, are involved in many soil processes that are of great importance in maintaining soil health and multifunctionality. Nevertheless, soil quality is still mainly characterized by physical, chemical, and microbiological parameters. Here, we assessed and compared the biological soil quality in woody (REF: reference forest, REM: remnant forest) and nonwoody (TURF: public turfgrass, and RUD: ruderal habitat) types of urban green spaces along a disturbance and management intensity gradient in the Budapest metropolitan area (Hungary), using community metrics and soil arthropod-based indicators. Vegetation cover and landscape characteristics of study sites were quantified through vegetation and urbanization indices, respectively. Basic soil properties, total and bioavailable concentrations of the main heavy metals (Cd, Co, Hg, Ni, Zn) were also measured. Acari, Collembola, and Hymenoptera (mainly Formicidae) were the most abundant groups. Litter-dweller taxa, particularly Protura, proved to be the most sensitive to urban disturbance. Representatives of Hemiptera, Diptera, Symphyla, and Pauropoda were common in low densities. The taxonomic diversity of soil arthropod assemblages in nonwoody and woody habitats was similar. Although the integrated faunal indices showed no differences among soil habitat types, they provided different responses and, consequently, different information. Our findings demonstrated that the biological quality and arthropod community structure of soils were strongly impacted by soil C/N and heavy metal contamination. We found that low and moderate levels of pollution have adverse effects on edaphic fauna, suggesting biological degradation of soils, even below pollution limits. Nevertheless, more disturbed urban green spaces have been shown to play a significant role in maintaining belowground biodiversity, thereby soil functions.

Contamination and health risk assessment of potentially toxic elements in soils of different kinds of land use in Lithuania

“…Sim i lar i ties were ob served in Pol ish soil, though in terms of ur ban soil, the mean con tent of Cd, Zn, Cu were higher than the back ground val ues of the Pol ish soils (Skorbi³owicz et al, 2021). In Hun gary, on av er age, the HM con cen tra tions were be low the pol lu tion limit val ues in ur ban green spaces (Tóth et al, 2023), whereas in green ter ri to ries of Lith u a nia Cu and Zn were found above the BC limit val ues. Living ter ri to ries such as cit ies all across the world dif fer from one an other in terms of pop u la tion den sity and rate of ur ban iza tion.…”

Metal Pollution Drives Earthworm Biodiversity in Urban Lawns

“…45% of the 174 studies on European urban soils did not provide data on standard deviation (Binner et al, 2023)). Furthermore, only a limited number of studies have explored the connection between MTE pollution and soil fauna communities, and the results obtained from these investigations vary considerably (Fiera, 2009;Pižl and Josens, 1995;Santorufo et al, 2012;Tóth et al, 2023;Yu et al, 2022). The scarcity of research in this area stands in stark contrast to the abundant literature available on MTE toxicity in soil organisms, particularly earthworms (Sivakumar, 2015;Yadav et al, 2023).…”