An effective tool for monitoring the deposition of surface dust in the cross-bio-indication process of metals in moss tissue

Mosses have been used for biomonitoring in a number of different ways which may lead to rather different results, and some kind of classification seems necessary at this point. Epigeic mosses (growing on the ground) are preferred in the regional surveys in Europe. Trace elements may be absorbed on the moss from the atmosphere either as soluble chemical species in wet deposition or contained in particles from dry deposition. Part of the trace element content of particulates may eventually be released by weathering and reabsorbed by the moss. Whereas uptake efficiencies for particulate-bound trace elements are generally poorly known, Ions may be subject to active uptake into cells or attached on the moss surface by physical and chemical forces. Methods are available to distinguish between intracellular and surface-bound fractions of elements. Main problem with issue moss-biomonitoring are reveal as: a) transport of soluble compounds from the soil into moss tissue, particularly during periods with excessive soil/water contact. Although mosses do not have a root system, influence from this source cannot be disregarded, in praticular in areas with low atmospheric deposition and b) windblown mineral dust from local soil. As far as the surface bound fraction is concerned, little is known about the binding mechanisms, but the fact that different metals show rather large differences in their retention capacitie, indicates that both simple cation exchange on negative surface charges and complex formation with ligands on the moss surface are involved. Laboratory analysis using scanning electron microscopy has been involved for determination of the dry deposition occurred within moss bioindicators. Moss surface screening can give us very useful information of the dust composition, and moss tissue accumulation of potentially toxic elements. Moss samples of Hypnum cupressiforme (Hedw.) and Homalothecium lutescens (Hedw.) were collected at the critical mining areas in the Eastern part of the Republic of North Macedonia (copper mine and Pb-Zn mine). Three sampling point were selected two critically affected and one control site. The scanning electron microscopy (SEM) was used for observation of specimen surfaces. Both types of moss, which have been proven to be effective bioindicators, were used in this study. But when examining large areas, it is necessary to use them alternately given their specific geographical distribution. Analyzes have shown that they have similar surface adsorption to dust particles, as well as insignificant variability in the chemical composition plant surface: extracted for the biogenic elements carbon and oxygen, macroelements Mg, Al, Si, K, Ca, and microelements Fe, Cu and Zn. Both moss species can be used interchangeable for dust deposition investigation