Distribution patterns of PAHs and trace elements in mosses Hylocomium splendens (Hedw.) B.S.G. and Pleurozium schreberi (Brid.) Mitt. from different forest communities: A case study, south-central Poland

Twenty samples of the moss species Hylocomium splendens and Pleurozium schreberi were collected at 10 sites of the Holy Cross Mountains (south-central Poland) and analyzed for 16 polycyclic aromatic hydrocarbons and 33 elements. The ring sequence of PAHs in the moss samples is: 4 (92–1040 ng  · g−1) > 3 and 5 (21–272 ng · g−1) > 6 (<5–131 ng · g−1). H. splendens accumulates PAHs more effectively than P. schreberi, and therefore the former may be regarded as a better bioindicator of PAHs. No correlation was found between concentrations of PAHs and elements. However, both H. splendens and P. schreberi shows different bioaccumulative capabilities depending on the plant communities. The mosses growing in the dry pine forest Cladonio-Pinetum   reveal higher levels of Fe, Na, Sr, Ti, Cr, Mo, Ni, V and higher mean concentrations of ∑∑16 PAHs, whereas those from the continental coniferous forest Querco roboris-Pinetum   are highlighted by elevated levels of B, Ca, K, Mg, Mn, P, Rb and Sb and lower mean concentrations of ∑∑16 PAHs. These differences seem to be brought about by a higher biodiversity of the second forest type and its higher productivity that favors more effective cycling of elements.