Occurrence of heavy metals (Cu, Ni, Pb and Zn) in mosses in Kozienicki Landscape Park and Tatra National Park
Ryszard Świetlik, Marzena Trojanowska, Artur Molik
Heavy metal pollution is regarded as one of the most serious threats to the natural environment and also as a factor contributing to a poor condition of the forests. In Poland, combustion in manufacturing industry and in the municipal and residential sectors is mainly responsible for the release of heavy metals into the air. In the case of Pb and Zn an important role is played also by production processes and, in the case of Ni, combustion in energy and transformation industries as well. Biomonitors are often used to study the immission of heavy metals and their deposition in forest areas. Due to their omnipresence, characteristic structure and high tolerance of pollution, mosses turned out to be particularly useful for evaluation of heavy metal deposition in forest areas, particularly Pleurozium schreberi (Schreber’s moss) which is very common in those areas. The aim of this study was to examine the content of heavy metals (Cu, Zn, Ni and Pb) in mosses occurring in Kozienice Landscape Park (KLP) and Tatra National Park (TNP) and to evaluate the pollution by the heavy metals of the two forest areas. Three moss species were used: Pleurozium schreberi, Hylocomium splendens and Polytrichum commune. Moss samples were collected from fve sites in KLP (including three nature reserves): Źródła Królewskie, Miodne and Załamanek
as well as Poborskie Łąki and Kozie Ługi. In the TNP area the samples were collected from three valleys: Dolina Lejowa, Dolina Chochołowska and Dolina Białego.
The mean metal content in the green parts of the mosses forms a decreasing order: Zn > Pb ≈ Cu > Ni which is similar to the order formed by emission levels of these metals in Poland: Zn (1447 Mg/year) > Pb (543 Mg/year) > Cu (368 Mg/year) > Ni (179 Mg/year). The contents of heavy metals in Pleurosium schreberi samples collected in the three TNP valleys do not differ signifcantly but the heavy metal content in the samples from Załamanek and Miodne nature reserves is considerably higher than in the other KLP areas. Taking into account the local factors, road traffc emission can be pointed out as a potential source of anthropopressure. Comparing the obtained values of the content of heavy metal with the literature data for other forest areas, the heavy metal emission hazard for the investigated TNP and KLP areas can be regarded as
relatively low. However, it is worth noting that the level of zinc was slightly higher in the Pleurozium schreberi samples (TNP – av. 94.9 mg/kg d.w. and KLP – 88.4 mg/kg d.w.).