Studia Quaternaria

The research on the content of polycyclic aromatic hydrocarbons (PAHs) in soil and grass ( Lolium perenne L.) was carried out on samples collected in the city of Białystok, in north-eastern Poland. The test samples came from green belts in the vicinity of communication routes, differentiated in terms of the surrounding buildings and infrastructure and characterized by a different car traffic intensity. The highest total concentration of all sixteen PAHs in soil and grass samples was found near a large intersection at Nicholas Copernicus Street, one of the most important communication routes connecting two parts of the city. In the aboveground parts of the studied grass samples, benzo[a]pyrene was the most abundant, its content ranging from 53.8 μg/kg DM up to 91.7 μg/kg DM. On the other hand, in soil samples, much higher benzo[a]pyrene content was found, and the dominance of this compound was observed in almost every measurement location. Based on the obtained results, it was found that car traffic is a significant source of PAH emissions to the urban soil environment and urban greenery. The squares and green belts located along communication routes and intersections are the most exposed to pollution.

This paper presents the concentrations of the polycyclic aromatic hydrocarbons (PAH) and heavy metals in leachates from the autothermal thermophilic aerobic digestion (ATAD). The leachates from ATAD installations (Dąbrowa Białostocka, Hajnówka, Pisz, Olecko, Giżycko, Wysokie Mazowieckie) located in Poland were tested. The concentrations of PAHs in samples from Pisz, Giżycko, Wysokie Mazowieckie and Hajnówka were similar to those in industrial wastewater. The cluster analysis confirmed that in sites with a higher polyethylene (p.e.) input from the industrial sector, the leachates were more contaminated with PAH compounds. In samples from Dąbrowa Białostocka, Olecko, Pisz and Hajnówka, the heavy fraction of PAHs compounds prevailed over the light fraction. Concentrations of heavy metals in leachates from ATAD varied. The Ward’s method isolated the wastewater treatment plant in Giżycko. The p.e. from the industrial sector was the highest for this facility. Also, the samples from ATAD had the highest total concentration of heavy metals (5.87 mg/l). The leachates from ATAD are returned to biological systems of municipal sewage treatment plants, where they can be combined into more toxic compounds. Biological wastewater treatment processes do not ensure the removal of PAHs and heavy metals from the wastewater. As a result, harmful compounds can get into the water or ground, polluting the environment.

The aim of the statistical analyses carried out was to identify similarities and to point out differences between the various tributaries of the Narew River, to identify the factors and processes responsible for the transformations occurring in the aquatic environment and finally, to identify the main sources of pollution in the river catchment. For the purposes of statistical analysis, the results of studies conducted as part of diagnostic monitoring by the General Inspectorate for Environmental Protection in 2017–2018 were used. The studies included 8 measurement points located directly on the Narew River and 17 points located on its selected left and right tributaries. Analysis of the collected results indicates that the chemical condition of the water in the Narew catchment is assessed as being poor. This observation may be due to the fact that the Narew catchment is mainly used for agricultural purposes and, in addition, there is a relatively large number of potential anthropogenic sources. As part of the analysis, two potential sources of pollution affecting water quality in the Narew catchment were identified, which include surface run-off and treated wastewater inflow.

Ditches and drainage canals are an important element in the post-bog meadows. Their basic function is to regulate air-water relations in ecosystems, mainly in agrocenoses. The environmental functions of ditches and canals consist of maintaining a large diversity of flora and fauna species due to high humidity of these ecosystems. The study of plant communities in the ditches in the post-bog meadows habitat of the Supraśl Dolna valley structure in 2010–2020 was carried out. There were 23–27 species of plants in the ditches. Species diversity did not change significantly during this period, while changes in individual species’ coverage and viability were found. The species were classified into two rush communities: reed rush ( Phragmitetum australis) and rush ( Phalaridetum arundinaceae). As a result of the lack of maintenance of the ditches, an invasive species of flapped barbed ( Echinocystis lobata) was found. The natural valorization carried out by the Oświt method showed that plant communities in the drainage ditches are in the lowest valorization classes.

In order to assess the possibility of using waste from agri-food processing for fertilization, residues in the form of apple pomace, carrot root, onion husks and dried nettle were selected for the tests. The research material came from food plants located in north-eastern Poland. In selected waste, the pH value, dry matter content, organic matter, nitrogen, phosphorus, potassium and carbon were determined. It was found that apple pomace, carrot root and onion husk were acidic and dried nettle was alkaline. The nitrogen content in the tested waste ranged from 0.61 to 2.29%, phosphorus from 0.07 to 0.55%, and potassium from 0.19 to 3.72%. Based on the results obtained, it was found that the examined post-production residues are characterized by good fertilizer properties. However, it should be remembered that fertilizers or soil improvers must meet a number of requirements and above all, they must be safe for the environment.