87
good association and between 0.7 and 1.0 points to the existence of a strong connection between elements. The values for the content of every element were correlated
with the values for the content of the other elements (Reimann et al. 2002). All correlation coefficients between all elements are represented in the matrix of correlation coefficients (Table 3.4).
In factor analysis the distribution is reduced to four synthetic variables (F1 to
F4). As it can be seen from the results obtained by factor analysis (Table 3.5), four
factors (i.e. associations of elements) were obtained: F1 (Fe, Al, V, Ni, Li, Cr, Co,
Ba, Pb, S and Mn), F2 (Cu, Mo, Ag and Zn), F3 (K, P, Na, Mg and Ca) and F4 (As
and Cd). A total of 23 elements were reduced by factor analysis to 22 elements,
which had a total factor loading of 74.9% of the variability (5). Boron was eliminated from further analysis because it had a low share of communality or low tendency to form independent factors.
The dendrogram obtained by the application of cluster analysis is given in
Fig. 3.4. In the dendrogram the elements are divided into two major clusters and
several sub-clusters according to the degree of correlation between them. The first
sub-cluster includes the elements Ag, Cu and Mo which are included in Factor 2 of
the matrix of loading of the dominant rotating factors (Table 3.5). The second subcluster is composed of Al, Fe, Cr, V, Li, Ni, Sr, Zn, Na, Co, Mn and Pb which belong
to Factor 1 of the factor analysis. The third sub-cluster consists of As and Cd which
belong to Factor 4, and the fourth sub-clusters include Ca, K, P, Mg and Na which
belong to Factor 3.
Table 3.3 The ratio of the
element average content in
top soil (T) samples and moss
samples (M)
Element
T/M
Al
−0.03
As
0.09
B
0.54
Ba
0.23
Ca
0.20
Cd
0.05
Co
0.01
Cr
−0.04
Cu
0.41
Fe
−0.07
K
0.22
Li
0.16
Mg
0.36
Mn
0.18
Na
−0.05
Ni
0.05
P
0.08
Pb
0.02
Sr
0.10
V
0.01
Zn
0.25
Bolded values show high correlation
3 Moss Biomonitoring of Air Pollution Around the Coal Mine and Bitol…
good association and between 0.7 and 1.0 points to the existence of a strong connection between elements. The values for the content of every element were correlated
with the values for the content of the other elements (Reimann et al. 2002). All correlation coefficients between all elements are represented in the matrix of correlation coefficients (Table 3.4).
In factor analysis the distribution is reduced to four synthetic variables (F1 to
F4). As it can be seen from the results obtained by factor analysis (Table 3.5), four
factors (i.e. associations of elements) were obtained: F1 (Fe, Al, V, Ni, Li, Cr, Co,
Ba, Pb, S and Mn), F2 (Cu, Mo, Ag and Zn), F3 (K, P, Na, Mg and Ca) and F4 (As
and Cd). A total of 23 elements were reduced by factor analysis to 22 elements,
which had a total factor loading of 74.9% of the variability (5). Boron was eliminated from further analysis because it had a low share of communality or low tendency to form independent factors.
The dendrogram obtained by the application of cluster analysis is given in
Fig. 3.4. In the dendrogram the elements are divided into two major clusters and
several sub-clusters according to the degree of correlation between them. The first
sub-cluster includes the elements Ag, Cu and Mo which are included in Factor 2 of
the matrix of loading of the dominant rotating factors (Table 3.5). The second subcluster is composed of Al, Fe, Cr, V, Li, Ni, Sr, Zn, Na, Co, Mn and Pb which belong
to Factor 1 of the factor analysis. The third sub-cluster consists of As and Cd which
belong to Factor 4, and the fourth sub-clusters include Ca, K, P, Mg and Na which
belong to Factor 3.
Table 3.3 The ratio of the
element average content in
top soil (T) samples and moss
samples (M)
Element
T/M
Al
−0.03
As
0.09
B
0.54
Ba
0.23
Ca
0.20
Cd
0.05
Co
0.01
Cr
−0.04
Cu
0.41
Fe
−0.07
K
0.22
Li
0.16
Mg
0.36
Mn
0.18
Na
−0.05
Ni
0.05
P
0.08
Pb
0.02
Sr
0.10
V
0.01
Zn
0.25
Bolded values show high correlation
3 Moss Biomonitoring of Air Pollution Around the Coal Mine and Bitol…