Soil texture as a key driver of polycyclic aromatic hydrocarbons (PAHs) distribution in forest topsoils

Abstract

Due to the dynamic development of civilization and the increasing demand for energy, pollution by harmful chemicals, including polycyclic aromatic hydrocarbons (PAHs) compounds, is a serious threat to forest soils. The aim of the study was to determine the role of texture in the distribution of polycyclic aromatic hydrocarbons (PAHs) and trace elements in forest soils. The areas with different texture ranging from sand through sandy loam to silt loam were selected for the study. The study was carried out in the Chrzanów Forest District in southern Poland (50° 7′ 18 N; 19° 31′ 29 E), which in one of the most intensive industrial emission zones in Europe. The soil samples for properties determination were collected from locations distributed on a regular grid 100 × 100 m (20 points). The samples were collected from the humus horizon (0–10 cm) after removing organic horizon. Basic chemical properties, heavy metal content, polycyclic aromatic hydrocarbons (PAHs) content and magnetic susceptibility values were determined in soil samples. Additionally, enzymatic activity and microbiological biomass was determined in the samples. Our study confirmed the importance of texture in PAHs distribution. A strong correlation between PAHs content and silt content in the soils studied was noted. The regression tree analysis confirmed the importance of the silt content, followed by soil organic carbon in PAHs distribution. Organic carbon content and nitrogen content played a predominant role in controlling the microbial activity. In our study, we did not note a relationship between enzymatic activity, microbiological soil biomass and the amount of PAHs. This may be due to the effective sorption and immobilization of PAHs by particles of fine fractions, especially silt. Obtained results confirmed the usefulness of magnetic susceptibility in the assessment of heavy metals contamination of forest soils. We noted high correlation between magnetic susceptibility value and heavy metals content. Moreover, the relationship between magnetic susceptibility and soil texture of the topsoil was also observed.

Anthropogenic impact on soils of protected areas—example of PAHs

“…Polycyclic aromatic hydrocarbons may also be released naturally into the environment as a result of e.g. volcanic activity or forest fires 26 , 34 . In conjunction with water vapour suspended in air, PAHs become components of smog.…”

Variability in Water Capacity of Small-Leaved Linden Associated with Both the Presence of Honeydew and Various Sources of Pollution

“…Many of these compounds show strong carcinogenic and mutagenic properties. On the other hand, the strong hydrophobic and lipophilic properties of most PAHs may be the reason for the easy accumulation of these compounds on the assimilation apparatus of plants [15], but also in the soil [16].…”

Analysis of influencing factors of phenanthrene adsorption by different soils in Guanzhong basin based on response surface method

“…At the same time the absorbed PAHs can also be desorbed with the solvent. Absorbed PAHs in soils will enter into the food chain through the plants metabolism, posing a serious threat to the ecological environment and human health 7 , 8 . Understanding the transport and fate of PAHs in soil environment is paramount to determinations of the PAHs risks to human health and the environment.…”