Are Natural or Anthropogenic Factors Influencing Potentially Toxic Elements' Enrichment in Soils in Proglacial Zones? An Example from Kaffiøyra (Oscar II Land, Spitsbergen).

Arctic soils may hold potentially toxic elements (PTE); PTE can provide evidence of past or recent pollution. In this study, five soil profiles located on Oscar II Land (Kaffiøyra) were studied to (i) evaluate the ecological status of Kaffiøyra's soils based on the determination of the possible accumulation of PTE using pollution indices; and (ii) determine the possible origin of PTE enrichment (local factors vs. long-range sources) depending on the distance from the sea. The soils were tested with standard soil science methods. The contamination of five soils was assessed by a wide spectrum of pollution soil indices: Enrichment Factor (EF), Geoaccumulation Index (Igeo), Potential Ecological Risk (RI), Pollution Load Index (PLI), and Probability of Toxicity (MERMQ). EF values calculated based on Cd, Cr, Cu, Pb and Zn content indicated an anthropogenic origin of the pollution. Values of Igeo showed the highest pollution with Cd, while CSI and MERMQ values indicated the highest Cd and Pb levels, but only in the soils located closest to the coast. RI values suggested that soils were under a strong or very strong potential ecological risk, whereas PLI confirmed the high probability of soil quality reduction. Enrichment with PTE has been conditioned by both local (natural) and long-distance (anthropogenic) factors. Among the local factors, parent material was highly relevant. The effect of long-distance anthropogenic factors, especially from European, large industrial centres, was manifested by the high content of PTE in soils located closest to the coastlines, delivered by a wet deposition and sea aerosols. The monitoring and assessment of arctic soil quality are useful practices for the verification of the sources of PTE pollution and the development of methods that can contribute to the protection and maintenance of these vulnerable ecosystems.

Soil pollution indices conditioned by medieval metallurgical activity - A case study from Krakow (Poland).

The studied soil profile under the Main Market Square (MMS) in Krakow was characterised by the influence of medieval metallurgical activity. In the presented soil section lithological discontinuity (LD) was found, which manifests itself in the form of cultural layers (CLs). Moreover, in this paper LD detection methods based on soil texture are presented. For the first time, three different ways to identify the presence of LD in the urban soils are suggested. The presence of LD had an influence on the content and distribution of heavy metals within the soil profile. The content of heavy metals in the CLs under the MMS in Krakow was significantly higher than the content in natural horizons. In addition, there were distinct differences in the content of heavy metals within CLs. Profile variability and differences in the content of heavy metals and phosphorus within the CLs under the MMS were activity indicators of Krakow inhabitants in the past. This paper presents alternative methods for the assessment of the degree of heavy metal contamination in urban soils using selected pollution indices. On the basis of the studied total concentration of heavy metals (Zn, Pb, Cu, Mn, Cr, Cd, Ni, Sn, Ag) and total phosphorus content, the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Sum of Pollution Index (PIsum), Single Pollution Index (PI), Nemerow Pollution Index (PINemerow) and Potential Ecological Risk (RI) were calculated using different local and reference geochemical backgrounds. The use of various geochemical backgrounds is helpful to evaluate the assessment of soil pollution. The individual CLs differed from each other according to the degree of pollution. The different values of pollution indices within the studied soil profile showed that LDS should not be evaluated in terms of contamination as one, homogeneous soil profile but each separate CL should be treated individually.