Concentrations of heavy metals and biogenic elements in needles of Norway spruce and Scots pine from Polish peatlands

Abstract The study characterised the content and spatial variability of heavy metals and selected biogenic elements (Cd, Co, Cr, Cu, Ni, Pb, Zn, Al, Ca, Fe, K, Mg, Mn, Na, P, N, C) in one-year-old needles of Norway spruce and Scots pine from 262 peatlands in Poland in the light of previous studies and norms, and to determine the relationship between the content of elements in needles and the types of Histosol (fibric, hemic, sapric). The spatial variation in heavy metal content in needles is not related to southern regions of Poland with high human footprint index which suggests that episodic local sources of pollution and transboundary transport of air pollutants are likely to influence their bioaccumulation. It is also not related to the type of Histosol or the pH of water and soil, which indicates that heavy metals accumulate mainly passively from the atmosphere. Despite exceeding the optimal values for some elements, heavy metal levels do not pose a toxicological risk. Elements such as chromium in spruce and cadmium in pine can serve as markers of the impact of industrial emissions on peatland ecosystems. The concentrations of the most studied elements in Poland were lower than in other European countries.