TOXICOLOGICAL STUDY OF MOSS COVER OF PINE FORESTS IN BIOGEOCHEMICAL LANDSCAPE OF BACKGROUND AREA OF UKRAINIAN POLISSIA. PART 1. HEAVY METALS

Tasks of this study – to investigate levels of contamination of soils of background forest area of Ukrainian Polissia by heavy metals (Cu, Cd, Pb, Zn); to evaluate of concentrations of these heavy metals in fractions of mosses; to calculate values of coefficient of biological absorption of heavy metals by fractions of moss species. Study was conducted in July 2021 at 3 experimental plots in Zhytomyr Region, Povchanske forest division of branch «Lugyny Forestry». Vegetation was presented by association Molinio-Pinetum Matuszkiewicz (1973) 1981, and by moist fairly infertile pine site type (В3). Moss were sampled by fractions: Pleurozium schreberi and Dicranum polysetum – increment of 1-2 years, increment of earlier period; Polytrichum commune – increment of the first year, increment of the second year, increment of earlier period; Leucobryum glaucum, Sphagnum capillifolium and S. palustre – increment of the first year, increment of the second year, peat litter (semi-decomposed). Measurement of heavy metals content was conducted on atomic-absorption spectrophotometer С-115-М1. Coefficient of biological absorption was used as an index of intensity accumulation of heavy metals by mosses in the chain «soil – moss». Concentrations of heavy metals in 10-cm soil layer changed in such range: Pb > Zn > Cu > Cd; in absolute values (mg·kg-1) – 3,75±0,06; 3,56±0,10; 1,10±0,05; 0,002±0,00. Specific distribution in fractions of all studied moss species – terrestrial and paludal – was found for concentrations of Cu – maximal concentration was in the increment of the first year with decrease to the increment of the second year and lower – to the old moss fraction. Opposite distribution in moss fractions was observed for Zn and Pb in all studied moss species. More complicated distribution in moss fractions was observed for concentrations of Cd. For terrestrial mosses, such as Pleurozium schreberi, Dicranum polysetum and Polytrichum commune this distribution was similar – decrease Cd concentrations from increment of the first year to increment of the second year and to the lower part of mosses, but for Sphagnum spp. was differ. An important conclusion can be made that ranged row of heavy metals accumulated in the upper moss part (increment of the first year) looks like this: Cd > Cu > Zn > Pb; in the increment of the second year – Cd > Zn > Cu > Pb; in the lower part of moss cover – Cd > Zn > Pb > Cu. Also general conclusion can be made that intake of each heavy metal is species-dependent as well as distribution of its concentration among moss fractions