Content of heavy metals in Carpathian soils (Poland)

The article addresses determining the concentration of six chemical elements: Cd, Cr, Cu, Ni, Pb, and Zn in the soils of the southern slope of the Jaworzyna Krynicka mountain in the Beskid Mountains. The research consisted of determining the diversity of metal content in soil samples taken at different altitudes (500, 600, 700, 800, 900, 1000, and 1100 m MSL). The test results indicated low soil contamination in the selected area, particularly for the altitudes of 500 and 900 m MSL. For these altitudes, the content of Cd, Cr, Cu, Ni, Pb, and Zn was similar to the concentration of these metals in uncontaminated soils. In the conducted research, very low Cd content was found for all absolute altitudes. The chemical element of metal whose content in the soils under study was the highest and exceeded natural values was Zn. All tested metals showed a common trend of increasing content in the soils up to 800 m MSL.

Introduction

Chemical elements of heavy metals are widespread in the natural environment. They pose a great threat to living organisms when introduced into the environment in excessive quantities [1-3]. Atmospheric dust containing heavy metals enters the soil. The source of metals in the soil is the bedrock and atmospheric pollution caused by industrial emissions and vehicle traffic. The natural content of heavy metals in soil is closely related to the type and kind of soil [3]. The exacerbation of metal deposition depends on the size of emissions, physical properties of dust, and weather conditions.

Metals with a high environmental risk were selected for the study. When these metals are introduced into the soil they accumulate and remain in the soil for a long period [4,5].

Due to the prolonged atmospheric dust, low pressure, and strong wind, heavy metals are displaced over considerable distances from emission sources [6,7]. This occurrence is observed, in particular, in mountainous areas, where plants and soil are contaminated with heavy metals despite the absence of sources of emissions of these metals in the immediate vicinity [8,9].

For research to observe the impact of long-range emissions on the size of the accumulation of heavy metals in soil, a mountainous area was selected [10]. Under the influence of such emissions, even naturally important areas such as the Beskid Mountains, are exposed to the effects of human activities (industry, traffic emissions, and nearby coal-fired towns). The spread of pollutants is influenced by altitude above sea level, as well as proximity to a major mountain ridge. The characteristic conditions of mountainous areas increase wind speeds, which may result in higher accumulations of metals in the soils of areas located at the highest altitudes.

It is an environmentally valuable area, located within the boundaries of the Poprad Landscape Park [11]. Many tourists and guests visit the site due to the Krynica-Zdrój and Muszyna sanatoriums and rest houses located there [12,13]. These towns are famous health resorts in Poland [14,15]. This region is also a popular Polish ski resort [16,17] and tourist area [18,19].

Materials and MethodsThe subject of the research was the area of the Carpathian Mountains in the Beskid Sądecki, Poland. Samples (10 samples per testing ground) were taken from seven testing grounds (A, B, C, D, E, F, and G) at altitudes of 1100, 1000, 900, 800, 700, 600, and 500 m MSL located in the area with southern exposure (Figure 1). In the study area there are light and medium loams, sometimes dusty, with skeletons of various sizes [20].

Figure 1: Location of testing grounds.

Climatic conditions in the mountainous area of the Beskids depend on many factors, including altitude above sea level, exposure, and terrain. The conditions prevailing there correspond to the habitat types of forests, in particular to the growth and development of mountain forests and mountain mixed forests. In the case of advective weather, situations with air inflow from the west (18.8%) as well as from the south and northwest prevailed, on average, in 11.0% of all cases [21]. Samples were taken in September 2022. The average temperature during sampling was 14 oC and no precipitation was recorded.

The laboratory work was carried out following the methodology used to collect and prepare samples for chemical analyses [22,23]. The content of heavy metal elements was determined by inductively coupled plasma mass spectrometry (ICP-MS) in the Bureau Veritas laboratory.

Results and discussion

The results of the research indicate that the concentrations of all tested metals, except for lead, increase to an altitude of 800 m MSL. Only the concentration of lead in the soil increases with the increase in altitude (Table 1). Perhaps such metal content in the soil is influenced by its pH and land cover. On the highest altitude testing grounds, there are beech forest habitats, while in the testing grounds located at altitudes of 800 - 700 m MSL, beech-spruce-pine mixed stands predominate, in the habitat of the mountain forest. Testing grounds at altitudes of 600 and 500 m MSL are grasslands, pastures, and arable fields. The value of soil reaction for individual sampling sites varied from very acidic for the highest areas: 1100-900 m MSL (pH in H₂O: 4.0-4.3), through acidic for areas from 800 - 700 m MSL (pH in H₂O: 5.5-6.3), to neutral or slightly acidic pH for areas at 600-500 m MSL (pH in H₂O: 6.2-7.2).

The contents of the tested metals in the soils of the southern slope of Jaworzyna Krynicka were compared with the global geochemical background (average content of the element in the Earth’s crust according to Turkian and Wedepohl [24]) and with the local geochemical background of Polish soils proposed by Czarnowska [25]. Generally, the contents of all tested heavy metals in the soils of Jaworzyna Krynicka are higher than the global and local geochemical background values. This may indicate anthropogenic pollution in the studied area. Traffic and industrial pollution resulted in increased content of heavy metals in mountainous and naturally valuable areas. The negative impact of human activity on environmental pollution was also observed by Paprotny, et al. [26], Małecka-Adamowicz, et al. [27], Kwiecińska-Poppe, et al. [28], Fabijańczyk, et al. [29] and Stankiewicz, et al. [30].

Conclusion

The average metal concentrations for the altitudes of 700 and 800 m MSL were the highest for copper, zinc, nickel, cadmium, and chromium. An increase in the content of these metals from an altitude of 500 to 800 m MSL was observed, and then a decrease in concentration from 900 to 1100 m MSL. Lead content increased with the increase in altitude.

The analysis confirms that metal pollution can occur even in areas with no metal emission. Especially mountain areas that constitute an orographic barrier to winds are exposed to the deposition of pollutants carried by winds from industrialized areas.

1. Nguyen HTH, Nguyen BQ, Duong TT, Bui ATK, Nguyen HTA, Cao HT, Mai NT, Nguyen KM, Pham TT, Kim KW. Pilot-Scale Removal of Arsenic and Heavy Metals from Mining Wastewater Using Adsorption Combined with Constructed Wetland. Minerals. 2019; 9:379. DOI:10.3390/min9060379.
2. García-Lorenzo ML, Crespo-Feo E, Esbrí JM, Higueras P, Grau P, Crespo I, Sánchez-Donoso R. Assessment of Potentially Toxic Elements in Technosols by Tailings Derived from Pb–Zn–Ag Mining Activities at San Quintín (Ciudad Real, Spain): Some Insights into the Importance of Integral Studies to Evaluate Metal Contamination Pollution Hazards. Minerals. 2019; 9:346. DOI:10.3390/min906034.
3. Kabata-Pendias A. Trace Elements in Soils and Plants. CRC Press, Boca Raton, FL, London, UK; 2010. pp. 15-204.
4. Rahmonov O, Sobala M, Środek D, Karkosz D, Pytel S, Rahmonov M. The spatial distribution of potentially toxic elements in the mountain forest topsoils (the Silesian Beskids, southern Poland). Sci Rep. 2024 Jan 3;14(1):338. doi: 10.1038/s41598-023-50817-7. PMID: 38172231; PMCID: PMC10764751.
5. Dołęgowska S, Sołtys A, Krzciuk K. Organic fermentative-humic soil subhorizon (Ofh) as a ‘natural sponge’ of selected trace elements: Does this feature make it a potential geoindicator of temperate soil quality? Land Degradation & Development. 2024;35(8):2673-2959.
6. Sörme L, Bergbäck B, Lohm U. Goods in the anthroposphere as a metal emission source. Water Air Soil Pollut. 2001; 1:213-227. DOI: 10.1023/A:1017516523915.
7. Steinnes E, Friedland AJ. Metal contamination of natural surface soils from long-range atmospheric transport: existing and missing knowledge. Environmental Reviews. 2006; 14:169-186. DOI: 10.1139/A06-002.
8. Korzeniowska J, Krąż P. Heavy Metals Content in the Soils of the Tatra National Park Near Lake Morskie Oko and Kasprowy Wierch - A Case Study (Tatra Mts, Central Europe). Minerals. 2020;10(12):1120. 14pp. DOI: 10.3390/min10121120.
9. Korzeniowska J, Krąż P, Dorocki S. Heavy Metal Content in the Plants (Pleurozium schreberi and Picea abies) of Environmentally Important Protected Areas of the Tatra National Park (the Central Western Carpathians, Poland). Minerals. 2021; 11:1231. https://doi.org/10.3390/min11111231.
10. Ciarkowska K, Miechówka A. Identification of the factors determining the concentration and spatial distribution of Zn, Pb and Cd in the soils of the non-forest Tatra Mountains (southern Poland). Environ Geochem Health. 2022 Dec;44(12):4323-4341. doi: 10.1007/s10653-022-01201-3. Epub 2022 Jan 10. PMID: 35014009; PMCID: PMC9675705.
11. Więckowski M. Natural heritage as a resource for tourism development in the Polish Carpathians. Geografický Časopis/Geographical Journal. 2020;72(3):243-259.
12. Węcławowicz-Bilska E, Vaščak M. Contemporary transformation of traditional Polish health resorts against the background of changes observed in balneological centers around the world. Technical Transactions. 2018;115(11):71-85.
13. Faracik AR, Kubal M, Kurek W, Pawlusiński R. The transformation of tourism model in the Polish Carpathians - reporting on the last 20 years of experiences. Zeszyty Naukowe Uniwersytetu Szczecińskiego. Ekonomiczne Problemy Turystyki. 2014; No.4:285-306. Ref. 25.
14. Wójcikowski WK. Muszyna Zdrój-10 years of spatial changes in the town and in the spa. Sws Journal of Social Sciences and Art. 2020;2(1):1-13.
15. Kwiek M, Korzeniowska J. Development of sports and recreational infrastructure in the Krynica-Zdrój commune in the last 10 years. In: Traditions and prospects for the development of spa culture in Muszyna in the European context, edited by Bożena Płonka-Syroka, Paweł Brzegowy, Andrzej Syroka and Sławomir Dorocki. Arboretum Publishing House, Medical University of Warsaw, Wrocław, 2020; 12:289-304.
16. Krzesiwo K. Contemporary development directions of ski resorts in Poland in the context of the idea of sustainable development. Works of the Industrial Geography Committee of the Polish Geographical Society. 2023;37(3):85-108.
17. Krzesiwo K, Mika M. 2024. A tourist business in a state of sustained uncertainty. An exploratory study of barriers to ski resort development in Poland. Current Issues in Tourism. 2024;27(8):1249-1264.
18. Gancarczyk M, Gancarczyk J, Reichel M. Revitalizing Forgotten Spaces through local leadership and social entrepreneurial ecosystems: The case of Muszyna commune. In: European Regional Policy and Development. Routledge; 2024. pp. 105-134.
19. Dryglas D, Klimkiewicz K. 2023. Emerging trends in employee competencies in Polish therapeutic tourism enterprises. International Journal of Spa and Wellness. 2023;6(1):157-175.
20. Firek A, Zasoński S. Preliminary studies of some properties of variously used soils in the southern parts of the Jaworzyna Krynicka range. Year. Soil. 1969; 20:99–118.
21. Durło G. The microclimatic typology of Jaworzyna Krynicka and the Czarny Potok Valley. Sylwan. 2003; 2:58–66.
22. Gajec M, King A, Kukulska-Zając E, Mostowska-Stąsiek J. Soil sampling in the context of soil pollution assessment. Nafta-Gas. 2018; 3:215–225.
23. Namieśnik J, Łukasiak J, Jamrógiewicz Z. Collecting Environmental Samples for Analysis. Wydawnictwo Naukowe PWN: Warsaw, Poland; 1995. pp. 67–96.
24. Turekian KK, Wedepohl DH. Distribution of the elements in some major units of the earth’s crust. Bull. Geol. Soc. Am. 1961; 72:175–192.
25. Czarnowska K. Total content of heavy metals in source rocks as a geochemical background of soils. 1996; 47:43–50.
26. Paprotny Ł, Kwapuliński J, Wianowska D, Gnatowski M, Kasprzyk-Pochopień J, Piekoszewski W. A Comparison of Co-Occurrence of Special Forms of Selected Metals in Soil, on the Example of Sycamore, Beech, and Spruce Forest Complexes in Urbanized and Non-Urbanized Regions of Tatra National Park. Polish Journal of Environmental Studies. 2024;33(5):1-10.
27. Małecka-Adamowicz M, Kicińska A, Smoleń S. Heavy Metal Accumulation in Different Components of Norway Spruce Ecosystems in The Tatra Mountains. Environmental Science and Pollution Research. 2018;25(3):2308.
28. Kwiecińska-Poppe E, Ciszek D, Bujakiewicz A, Pająk M. Comparison of The Content of Heavy Metals in Tree Stands of Various Ages in The Gąsienicowa Valley in The Tatra National Park. Sustainability. 2020;12(15):6122.
29. Fabijańczyk P, Ziółkowska M, Biziuk M, Mechlinska A. Using Tree Rings of Pinus Mugo Turra as an Indicator of Metal Contamination in Tatra National Park. Environmental Monitoring and Assessment. 2021;193(4):190.
30. Stankiewicz A, Kempers AJ, Samecka-Cymerman A, Kolon K. Ecophysiological Aspects of Metal Accumulation by Vaccinium Myrtillus L. In The Tatra National Park, Poland. Environmental Science and Pollution Research. 2020;27(30):37677.