Mutual relations between PAHs derived from atmospheric deposition, enzymatic activity, and humic substances in soils of differently urbanized areas

Abstract

Purpose The aim of this study was to determine the mutual relations between polycyclic aromatic hydrocarbons (PAHs) originated from atmospheric emissions and enzymatic activity and humic substances in soils at differently urbanized area, on an example of the Lublin city, east Poland. Materials and methods The chosen areas represented three differently urbanized environments: old tenement houses and modern residential blocks, mixture of different building and rural landscape, and typical rural environment with smallholding farms, respectively. On each of the urban, suburban, and rural areas, one representative plot was chosen on fallow lands classified as luvisol derived from loess. The soil samples were collected from the top 25 cm layer. The following properties were determined: pH, organic carbon, total nitrogen, humic and fulvic acids, PAHs content (14 PAHs from US EPA list), and the activities of the following enzymes: dehydrogenases, acid phosphatase, alkane phosphatase, protease, and urease. Results and discussion Higher contents of organic C and total N were found in the rural soil samples. The share of humic acid was similar in all soils investigated, ranging from 19.38 to 25.27%, while fulvic acid values differ significantly between urban and rural areas. The urban soils indicated much lower share of fulvic acids (9.78-10.99%) than those of rural (29.02-29.32%). Consequently, the values of the C HA :C FA ratio of the urban soil were approximately two times higher than those of the rural soil. The results showed that both the rate of humification and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases in the soils increased in the following sequence: urban < suburban < rural. Conclusions The results showed that an increase of PAHs in the urbanized areas affect other soil properties. The phenanthrene/ anthracene and fluoranthene/pyrene ratios pointed to coal combustion as the principal source of PAHs in the investigated soils. The PAH content in the urbanized area inhibit humification processes in the soil and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases.

Soil organic matter composition as a factor affecting the accumulation of polycyclic aromatic hydrocarbons

“…Polycyclic aromatic hydrocarbons (PAHs) exhibit recalcitrant properties in soils, and some of them are potentially mutagenic/carcinogenic and teratogenic for human beings (Agarwal et al 2009). The PAHs emitted into the atmosphere are ultimately deposited (dry or wet deposition processes) onto soils (Maliszewska-Kordybach et al 2009;Duan et al 2015;Wang et al 2015;Klimkowicz-Pawlas et al 2017;Bielińska et al 2018) and sediments (Luo et al 2006;Wang et al 2014;Aemig et al 2016), where they tend to accumulate. PAH diagnostic ratios may provide an important tool for the identification of pollution emission sources.…”

Residues of Persistent Organic Pollutants (POPs) in Agricultural Soils Adjacent to Historical Sources of Their Storage and Distribution—The Case Study of Azerbaijan

“…The highest average concentrations were characteristic for four-ring compounds, such as: Chry (391.8 mg kg −1 ), Fla (214.3 mg kg −1 ), Pyr (141.3 mg kg −1 ), and BaA (16.2 mg kg −1 ), while the sum of two ring (Nap) and three ring (Acy, Ace, Fl, Phe, and Ant) PAH compounds, as well as five ring (Bbf, BkF, and BaP) and six ring (IcdP, DahA, and BghiP) compounds were present at much lower concentrations, with the average values of 4.1 mg kg −1 and 2.1 mg kg −1 , respectively. Despite the very high average concentrations of some individual PAHs, the median value of Σ16PAHs was generally low, at the level of 0.7 mg kg −1 , which still gives a much higher content than that recorded from China [39], Japan [40] or European countries, such as Norway [41], Poland [15,18,42,43], and Czech Republic [19].…”

Preface: humic substances in the environment

“…The general aspects of HSs, as basis for life, are presented by Frimmel and Abbt-Braun (2018), while the majority of papers focus on more specific issues. Among them are three papers related to interactions with pesticides and PAHs Bielińska et al 2018;Ćwieląg-Piasecka et al 2018). Another two contributions deal with dissolved organic matter (DOM) in arable soils (Rosa and Debska 2018) as well as in an Antarctic soil core (Lepane et al 2018).…”