This bio-monitoring is based on the positive correlation between heavy metal concentrations in the atmospheric depositions and their concentrations in the mosses. The evaluation of pollutant loads of the mosses by heavy metals can be expressed by pollutant load coefficients (K_z), which can be calculated by equation:

                    particular heavy metal concentration in the mosses of SR
         K_z = ----------------------------------------------------------------------------------------------------
                        ^*limit value of the particular heavy metal in the mosses of northern Norwegia

Note: ^* Check plots in Norwegia represented the territory of Europe with minimum - recorded atmospheric deposition of heavy metals in the Europe
 

        Table below presents average pollutant load coefficients (K_z) in the mosses of SR calculated for particular heavy metals as well as total pollutant load coefficients (K_{z (total)}) for the period 1991 to 1997.
 

Trend in the both average pollutant load coefficients (K_z) of particular heavy metals and total pollutant load coefficients (K_{z total}) in the long-term monitoring plots (TMP) of mosses of SR
 

Elements	Pollutant load coefficient (Kz)
	Europe	Slovak Republic
	1991	1991	1995	1996	1997
As	1	-	-	2.5 ± 2.6	3.1 ± 5.3
Cd	1	6.4 ± 2.7	6.6 ± 2.1	1.3 ± 0.6	3.8 ± 2.2
Cr	1	5.2 ± 4.5	12.4 ± 6.9	2.8 ± 1.3	6.9 ± 5.2
Cu	1	4.7 ± 2.9	4.7 ± 2.6	5.3 ± 3.1	4.5 ± 2.1
Fe	1	3.6 ± 2.0	2.7 ± 1.7	2.3 ± 2.3	1.5 ± 1.0
Hg	1	-	6.4 ± 4.3	4.9 ± 2.8	10.7 ± 8.5
Ni	1	1.7 ± 1.4	2.3 ± 2.0	2.4 ± 1.8	6.1 ± 3.4
Pb	1	12.3 ± 10.1	5.6 ± 4.5	1.8 ± 1.1	4.1 ± 2.8
V	1	-	0.8 ± 1.7	1.9 ± 1.0	4.8 ± 5.9
Zn	1	4.4 ± 1.4	1.4 ± 0.9	1.3 ± 0.3	1.3 ± 0.6
Total KZ (total)	1	5.5 ± 3.1	4.8 ± 3.4	2.7 ± 0.3	4.7 ± 2.6

                                                                                                        Source: LVÚ Zvolen

         Heavy metals may be transported across national boundaries before ending up in soil, sediments or biota. Map presented below shows the pattern of deposition of cadmium in Europe, from the bio-monitoring plots of mosses. Cadmium comes mainly from diffuse sources and is widely dispersed. Point sources are generally less important then for other heavy metals. Concentrations tend to fall from south to north, with some “hot spots” in industrial areas (Dobríš+3 Report).

Cadmium  in Mosess , early 1990 s