The distributions of the analysed trace elements (Cu, Pb, Zn, Ni, Co, Mn, As, U, Th, Sr, Cd, V, La, Cr, Ba, Sc, and Se) in the subsoil of the study area were found to vary in concentrations (in ppm) from one sample location to the other. The concentrations of Cu in the subsoil ranged from 9.26ppm, as found in location IDS16, to 76.28ppm as found in location IDS12. The average (mean) concentration of Cu was 40.00 ppm, with a standard deviation of 20.50. Locations IDS13, IDS19 and IDS7 were found to have relatively low concentration of 14.82, 17.65 and 15.16 ppm respectively, while locationsIDS4, IDS17 and IDS20 recorded relatively high concentrations of 63.09, 62.05 and 72.54ppm respectively. Pb concentrations (ppm) in subsoil ranged from 16.4 as recorded in locationIDS16 to 36.6 as found in location IDS2. The mean concentration (ppm) of Pb in the study area was 40.0, with a standard deviation of 5.5. The concentrations of Pb in the subsoil also recorded relatively low values ( in ppm) in locations IDS14 (17.55) and IDS19 (18.38). Similarly, Zn exhibited varying concentrations in ppm, in the subsoil of the study area, with lowest concentration (19.5) recorded in location IDS19, while the highest concentration (134.1) was found in location IDS18. The mean concentration was found to be 56.3 ± 25.8 as the standard deviation. Other locations with relatively low concentration in ppm were, IDS3 (32.0), IDS16 (33.9) and IDS6(39.0). Relatively higher concentrations were recorded in locations IDS5 (91.2 ppm), IDS21 (74.0 ppm) and IDS20 (75.3 ppm) among other locations. Similar variations in concentrations of the other analysed elements were also observed in the subsoil samples (Table 2). The average concentrations of some of the trace elements in the subsoil were found to be lower than the average concentrations of both the granite gneiss and pegmatite. Such elements include: As, Sr and Ba.The concentrations of these elements in the subsoildecrease in the following order: Mn>Ba>La>Zn>V>Cu>Cr>Cr>Pb>Co>Sr>Th>Ni>Sc>U>Se>As>Cd.
The mean value of As in the subsoil was 0.9 ppm, which is slightly higher than that in the granite gneiss 1.0 ppm and pegmatite 1.1 ppmm (Table 2). Sr in the subsoil also recorded much more lower average value 21.1 ppm, as against 255.1 ppm and 257.1 ppm in pegmatite and granite gneiss respectively.
The mean concentration in ppm of Cu in the subsoil (40.0) was found to be far lower than that of pegmatite (128.4), but higher than granite gneiss (22.9). Similar pattern of concentration variation in the subsoil,relative to the underlying rocks (granite gneiss and pegmatite), were observed in Pb, Zn, U among other elements (Table 2).
A Comparative analysis of the trace elements in the subsoils and the two rock types (granite gneiss and pegmatite) underlying the study area, were also carried out using the boxplots in Figures 3 (a-q). From the plots, higher concentrations of Ba was found in both the pegmatite and the granite gneiss compare to thatin the subsoil. Similar trend were recorded in As, Cd, Sr and Zn. However, different enrichment patterns were observed in Co, Cr, Cu, Mn, Ni, Sc, and V. In these elements, the concentrations in pegmatite were relatively higher compared to the subsoil and the concentrations of these elements were much lower in the granite gneiss. It was also observed that La, Pb, Th and U were found to be higher in concentration in the granite gneiss than in the subsoil. Since the study area is essentially underlain by granite gneiss, covering about 90% of the rock within the study area, it could be inferred that the rock (granite gneiss) may have contributed greatly in the enrichment of the elements in the subsoil through effect of weathering and erosion in the formation the soil in the study area.
Table 2
Summary Results of Trace Elements (ppm) in the Subsoils, Granite Gneiss and Pegmatite Rocks
|
|
Subsoiln = 21
|
|
|
Pgmn = 5
|
|
GGN n = 8
|
|
Elements
|
Max
|
Min
|
Mean
|
STDV
|
Max
|
Min
|
Mean
|
Stdv
|
Max
|
Min
|
Mean
|
Stdv
|
Cu
|
76.28
|
9.26
|
40.0
|
20.5
|
219.6
|
4.6
|
128.4
|
109.3
|
91.7
|
3.8
|
22.9
|
28.4
|
Pb
|
36.6
|
16.4
|
24.7
|
5.5
|
30.6
|
8.4
|
17.0
|
9.8
|
126.6
|
25.5
|
61.4
|
37.5
|
Zn
|
134.1
|
19.5
|
56.3
|
25.8
|
145.9
|
68.0
|
108.8
|
35.3
|
115.1
|
7.8
|
64.6
|
31.2
|
Ni
|
15.2
|
4.9
|
9.9
|
3.1
|
191.6
|
3.4
|
130.5
|
81.4
|
16.3
|
2.7
|
7.3
|
4.4
|
Co
|
38.6
|
4.5
|
21.8
|
8.7
|
72.4
|
10.6
|
56.2
|
25.7
|
17.3
|
1.3
|
7.2
|
4.5
|
Mn
|
2267
|
79
|
1099.3
|
541.7
|
1923.0
|
1303.0
|
1683.0
|
243.9
|
992.0
|
123.0
|
468.1
|
304.4
|
As
|
2.3
|
0.1
|
0.9
|
0.5
|
1.4
|
0.8
|
1.1
|
0.3
|
1.4
|
0.8
|
1.0
|
0.2
|
U
|
4.1
|
1.3
|
2.7
|
0.7
|
1.6
|
0.7
|
1.3
|
0.4
|
8.2
|
0.6
|
2.6
|
2.5
|
Th
|
30.9
|
10.6
|
19.0
|
5.9
|
23.9
|
2.5
|
9.8
|
9.9
|
266.7
|
2.1
|
72.7
|
83.8
|
Sr
|
46.5
|
12.4
|
21.1
|
8.3
|
666.0
|
127.0
|
255.2
|
230.1
|
503.0
|
161.0
|
257.4
|
107.8
|
Cd
|
0.19
|
0.01
|
0.1
|
0.0
|
0.4
|
0.2
|
0.3
|
0.1
|
0.3
|
0.0
|
0.1
|
0.1
|
V
|
104
|
31
|
55.9
|
25.1
|
322.0
|
47.0
|
214.8
|
139.1
|
83.0
|
4.0
|
29.4
|
24.3
|
La
|
207
|
36.6
|
78.5
|
37.3
|
110.1
|
27.4
|
51.8
|
35.1
|
293.6
|
3.0
|
127.7
|
114.3
|
Cr
|
124.2
|
13.7
|
36.9
|
29.9
|
361.0
|
13.0
|
266.2
|
144.2
|
44.0
|
5.0
|
18.0
|
12.4
|
Ba
|
365.2
|
72.7
|
197.6
|
74.2
|
2496.0
|
341.0
|
788.4
|
954.8
|
2485.0
|
443.0
|
1338.0
|
621.0
|
Sc
|
15.2
|
3.5
|
8.9
|
2.8
|
47.3
|
16.6
|
36.6
|
12.0
|
17.7
|
0.5
|
6.9
|
6.8
|
Se
|
1.7
|
0.1
|
1.0
|
0.4
|
0.8
|
0.3
|
0.6
|
0.2
|
0.6
|
0.3
|
0.5
|
0.1
|
Interelemental relationship
The reative association of the trace elements in the geomedia, (subsoil, granite gneiss and pegmatite) were evaluated, using Pearson correlation cooefficient (Bivariant plots) in Figure 4 (a-g), while coefficient of detrmination, principal component analysis and cluster (Deodegram) analysis were carried out on the subsoil trace elements.
For the pearson correlation analysis (R2), the correlation between Cr and Zn showed relatively fair R2 of 0.529 for subsoil, weak R2 of 0.151 for GGN and very weak R2 of 0.015 for PGM. TheR2 of Cr and V showed fair correlation of 0.511 for subsoil, strong correlation of 0.618 and 0.771 for GGN and PGM respectively. The R2of Th and U had relatively strong correlation of 0.785 and 0.656 for both subsoil and GGN, but very weak correlation for PGM. The correlation of Cd and As exhibitted relatively fair association of 0.403 and 0.540 for subsoil and GGN respectively, but weak correlation of 0.011 for PGM. Strong correlation was observed between Mn and Co. The values of R2 are 0.680, 0.583 and 0.852 for the subsoil, GGN and PGM respectively. In the same vain, the correlation of La and Th was such that the subsoil showed very strong R2value of 0.929, while very weak correlation of 0.124 and 0.013 for both GGN and PGM. V and Cu also showed very strong correlarion of 0.994 for GGN but very weak to negative correlation of 0.023 and – 0.410 for PGM and subsoil, Figure 4 (a-g). Elemental associations with strong R2suggest that these elements may have been enriched in the geomedia by similar sources. On the other hand, elements in the geomedia with relatively weak to negative correlation depict non similarity of enrichment sources.
The correlation matric of the trace elements in the subsoil showed varying degree of correlation(Table 3). From the correlation coefficient ( r ), it was observed that it ranges from negative correlation of – 0.4, between Th and Cu, to very strong correlation of 0.9, between Cd and Mn. Relatively fair to strong correlation were found between Mn/Cu (0.7), As/Pb (0.7), Mn/Zn (0.6), Co/Ni (0.6), La/Zn (0.8), Cr/V (0.8) among others. The relatively fair to strong correction of these trace elements in the subsoils suggests that their enrichment possibly may have been from similar (analogous) sources. Nevertheless, some other elements also showned negative to weak correlation. Examples are: Se/V (-0.4), Se/Cr (-0.3) among others.
The subsoil data were further subjected to Principal Component Anaysis (PCA) with varimax rotation. From the results, a total of five factors with eigen value greater than 1.0 and accounting for 85.74% of the data variability were extracted and considered appropriate (Table 4). The first factor, Zn, V, La, Cr, Ba, Sc and Se, accounted for 23.04% of the model. This elemental association probably suggest the scavenging activities of hydrous Fe-Oxide on these elements and the lithophile – silicate mineral association in the underlying granite gneiss.This factor, therefore, probably suggests environmental controls and that the enrichment in the soils may have been from the same source. The second factor, Cu, Co, Mn and Cd, accounted for 20.6% of the variability of the model. The strong positive correlation of Mn with Cu (0.7), Co (0.8) and Cd (0.9) probably indicates the scavenging action of Mn on these elements it is associated with. According to Loganathan and Burau, (1973) and Burns, (1976), Co and Mn – oxides occur together in the secondary environment as a result of the substitution of Co with Mn – Oxides as well as the adsorption of Co on the surface of Mn – oxides. This metal association could be interpreted as environmental factor. elemental affinity may have been associated with lithologic association with pegmate veins that are present in the study area. And since Mn-Oxide can effectively associate with large number of elements, hence the affinity of Mn with Cu, Co and Cd.. The third factor, Ni, Co, U, Th, V and Sc, which accounted for 20.07% of the variability of the model may be interpreted as a lithological factor.These metal association was probably influenced by insitu weathering of pegmatite veins present in the granite gneiss. Thorium is usually associated with uranium in granitic rocks as well as pegmatite with monazite being the possible source of Th. Pb, As and V constitute the fourth factor. This factor accounted for 13.43% of the variability of the model. These elemental association could be partly due to lithological or mineralization. The source of Pb could be from feldspar in the granite gneiss or probably the pegmatite in the area. Wedephol (1970) has reported the Pb in K-feldspar as the element can substitute for K. Pb could also be found in other minerals such as quartz, albite, biotite, muscovite as well as some accessory minerals like beryl, zircon etc. The strong positive correlation between Pb ans As could possibly suggest the presence of some sulphide mineralization in the underlying gneisses in the area. And the fifth factors were Sr and Ba elements association these two elements accounted for 8.59% of the total eugen values.These elements have been reported to be in strong affinity with potassium (K) in felsic rocks, which probably may have influensed the relative enrichment of these trace elements in the soil. A similar trend was exhibited by the Bi-plot (Figure 5) which showed a strong correlation between La, Ba and Mn; U and Th; Cu and Se and weak correlation between Cu and Zn. The biplot further revealed two distrinct elemental associations with sub-groups such as Ni, U, Th, V and Co; Cu, Mn, Cd; and Zn, La, Ba. These associations are similar to the elemental associations obtained from the PCA analysis, as earleir explained. In the case of the dendograme, there are two main clusters: Cluster I contains only Mn, while Cluster II contains all the other elements. This analysis is in agreement with the results of the Factor analysis. One of the dominant processes in the secondary geochemical environment is the scavenging action of Mn – oxides on other metals (Figure 6).
Table 3
Correlation Coefficients of trace elements in the analysed subsoil of the study area
Cu
|
Pb
|
Zn
|
Ni
|
Co
|
Mn
|
As
|
U
|
Th
|
Sr
|
Cd
|
V
|
La
|
Cr
|
Ba
|
Sc
|
Se
|
|
1
|
0.3
|
0.3
|
0
|
0.4
|
0.7
|
0.1
|
-0.3
|
-0.4
|
0.3
|
0.6
|
-0.2
|
0.2
|
0.2
|
0.2
|
-0.1
|
0.5
|
Cu
|
|
1
|
0.2
|
0.1
|
0.4
|
0.4
|
0.7
|
0.2
|
0.4
|
0
|
0.2
|
0.3
|
0.2
|
0.2
|
0
|
0.3
|
0.3
|
Pb
|
|
|
1
|
0.3
|
0.1
|
0.6
|
0.2
|
0.3
|
0.3
|
0.2
|
0.6
|
-0.1
|
0.8
|
-0.1
|
0.8
|
0.5
|
0.6
|
Zn
|
|
|
|
1
|
0.6
|
0.3
|
0.2
|
0.7
|
0.5
|
0.4
|
0.1
|
0.5
|
0.2
|
0.2
|
0.3
|
0.3
|
-0.1
|
Ni
|
|
|
|
|
1
|
0.8
|
0.3
|
0.3
|
0.1
|
0.2
|
0.6
|
0.4
|
0.1
|
0.4
|
0.2
|
-0.1
|
0.1
|
Co
|
|
|
|
|
|
1
|
0.2
|
0
|
-0.1
|
0.3
|
0.9
|
-0.1
|
0.5
|
0.1
|
0.5
|
0.1
|
0.5
|
Mn
|
|
|
|
|
|
|
1
|
0.4
|
0.5
|
0.1
|
0.1
|
0.6
|
0.1
|
0.4
|
0.1
|
0.3
|
0.2
|
As
|
|
|
|
|
|
|
|
1
|
0.8
|
-0.1
|
-0.1
|
0.6
|
0.1
|
0.2
|
0.1
|
0.5
|
-0.2
|
U
|
|
|
|
|
|
|
|
|
1
|
-0.2
|
-0.3
|
0.5
|
0.4
|
0.1
|
0.1
|
0.7
|
-0.1
|
Th
|
|
|
|
|
|
|
|
|
|
1
|
0.3
|
0.1
|
0.1
|
-0.1
|
0.5
|
0.1
|
0.1
|
Sr
|
|
|
|
|
|
|
|
|
|
|
1
|
-0.2
|
0.4
|
0.1
|
0.6
|
-0.2
|
0.5
|
Cd
|
|
|
|
|
|
|
|
|
|
|
|
1
|
-0.3
|
0.8
|
-0.2
|
0.1
|
-0.4
|
V
|
|
|
|
|
|
|
|
|
|
|
|
|
1
|
-0.3
|
0.6
|
0.4
|
0.5
|
La
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1
|
-0.3
|
-0.2
|
-0.3
|
Cr
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1
|
0.4
|
0.6
|
Ba
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1
|
0.4
|
Sc
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1
|
Se
|
Table 4
Correlation Coefficient of Trace Elements in the Subsoil in the Study area
|
1
|
2
|
3
|
4
|
5
|
Cu
|
|
0.72
|
|
|
|
Pb
|
|
|
|
0.865
|
|
Zn
|
0.818
|
|
|
|
|
Ni
|
|
|
0.803
|
|
|
Co
|
|
0.804
|
0.409
|
|
|
Mn
|
|
0.91
|
|
|
|
As
|
|
|
|
0.878
|
|
U
|
|
|
0.901
|
|
|
Th
|
|
|
0.754
|
|
|
Sr
|
|
|
|
|
0.949
|
Cd
|
|
0.85
|
|
|
|
V
|
0.508
|
|
0.686
|
0.411
|
|
La
|
0.838
|
|
|
|
|
Cr
|
0.586
|
|
|
|
|
Ba
|
0.764
|
|
|
|
0.492
|
Sc
|
0.639
|
|
0.401
|
|
|
Se
|
0.732
|
|
|
|
|
Eigen Total Value
|
3.916
|
3.504
|
3.412
|
2.282
|
1.46
|
% of Variance
|
23.035
|
20.613
|
20.073
|
13.426
|
8.588
|
Cumulative %
|
23.035
|
43.648
|
63.721
|
77.147
|
85.735
|
The mean concentration of the trace elements in the subsoil, granite gneiss and pegmatite and the mean concentration of some trace elements in soils of published researched works, particularly in agricultural and urban soils in Nigeria are presented in Table 5. Also included in the table are concentrations of trace elements from other parts of the world as well as average world shale concentration. From the results, mean concentration of Cu in the study area subsoil is found to be higher that the Cu concentration in Agricultural soils, Assiut governorate, Egypt (Abou El-Anwar et al., 2019), soil of Agricultural Sites in Sri Lanka (Jayawardana et al., 2013), Cerrado Soils, Brazil (Marques, et al., 2004), Agricultural Soil in Dexing area (Teng et al. 2010), Background Concentrations of Trace and Major Elements in California Soils (Bradford et al., 1996) as well as the Average Earth Crust metal concentration (Turekian and Wedepohl, 1961). But with lower Cu concentration in Agricultural Soil of Aswan area, South Egypt (Darwish and Pollmann, 2015) as well as top and sub soil of Ile - Ife area (Asowata and Akinwumiju, 2020). The mean concentration of Pb in the subsoil in this study is found to be slightly higher compared to soil of Agricultural Sites in Sri Lanka (Jayawardana et al., 2013). And the mean Pb concentration, from this study, is significantly lower compared to the data from other soils in Egypt, Sri Lanka, among other areas of comparison (Table 5). Similarly, the mean Zn concentration, in subsoil of this study, is found to be significantly lower compared to the data from most of the areas of comparison except in Cerrado soils, Brazil (Marques, et al., 2004).
The mean concentrations of the other elements in the subsoil, from this study, are comparatively lower than the concentrations from most of the selected areas of comparison (Table 5). This suggests that that the sources of these elements are essentially geogenic rather than anthropogenic.
Table 5
Comparison of The Studied Subsoil, Granite Gneiss, Pegmatite (ppm) with other Soil studied in other areas
|
Soil
|
Pgm
|
GGN
|
A
|
B
|
C
|
D
|
E
|
F
|
G
|
H
|
I
|
Elements
|
Mean
|
Mean
|
Mean
|
|
|
|
|
|
|
|
|
|
Cu
|
40.0
|
128.4
|
22.9
|
31.6
|
47.2
|
25.0
|
33.0
|
33.0
|
71.1
|
76.6
|
28.7
|
50
|
Pb
|
24.7
|
17.0
|
61.4
|
38.4
|
31.69
|
21.0
|
26.0
|
39.0
|
93.5
|
77.9
|
23.9
|
20
|
Zn
|
56.3
|
108.8
|
64.6
|
119.3
|
1390
|
75.0
|
38.0
|
81.0
|
826
|
622.3
|
149.0
|
95
|
Ni
|
9.9
|
130.5
|
7.3
|
84.2
|
58.19
|
40.0
|
14.0
|
|
25.3
|
27.2
|
57.0
|
50
|
Co
|
21.8
|
56.2
|
7.2
|
35.4
|
38.17
|
|
5.0
|
|
24.6
|
28.7
|
14.9
|
19
|
Mn
|
1099.3
|
1683.0
|
468.1
|
1180.6
|
858.1
|
|
455.0
|
275.0
|
1323
|
1190
|
646.0
|
850
|
As
|
0.9
|
1.1
|
1.0
|
15.4
|
|
3.0
|
|
10.0
|
3.1
|
3.4
|
3.5
|
13
|
U
|
2.7
|
1.3
|
2.6
|
|
|
|
3.0
|
|
|
|
4.7
|
-
|
Th
|
19.0
|
9.8
|
72.7
|
|
|
|
15.0
|
|
4,3
|
4.5
|
15.7
|
12
|
Sr
|
21.1
|
255.2
|
257.4
|
|
206.9
|
|
|
|
32.9
|
30.6
|
128.0
|
170
|
Cd
|
0.1
|
0.3
|
0.1
|
1.4
|
19.69
|
|
|
0.2
|
1.42
|
1.28
|
0.36
|
0.3
|
V
|
55.9
|
214.8
|
29.4
|
|
|
|
257.0
|
|
142.6
|
161.7
|
112.0
|
130
|
La
|
78.5
|
51.8
|
127.7
|
|
|
|
83.0
|
|
32.2
|
34.0
|
20.3
|
43
|
Cr
|
36.9
|
266.2
|
18.0
|
116.7
|
133.1
|
123.0
|
112.0
|
|
108.8
|
128.5
|
122.0
|
90
|
Ba
|
197.6
|
788.4
|
1338.0
|
|
|
|
67.0
|
|
|
|
461.0
|
580
|
Sc
|
8.9
|
36.6
|
6.9
|
|
15.15
|
|
21
|
|
|
|
9.5
|
13
|
Se
|
1.0
|
0.6
|
0.5
|
|
|
|
|
|
|
|
0.06
|
0.89
|
A:Agricultural Soils, Assiut governorate, Egypt (Abou El-Anwar et al., 2019)
B: Agricultural Soil of Aswan area, South Egypt (Darwish and Pollmann, 2015)
C: Soil of Agricultural Sites in Sri Lanka (Jayawardana et al., 2013)
D: Cerrado Soils, Brazil (Marques, et al., 2004)
E: Agricultural Soil in Dexing area (Teng et al. 2010)
F: Urban Topsoil in Ile-Ife, Nigeria (Asowata and Akinwumiju, 2020)
G: Urban Subsoil in Ile-Ife, Nigeria (Asowata and Akinwumiju, 2020)
H: Background Concentrations of Trace and Major Elements in California Soils:(Bradford et al., 1996)
I: Average Earth Crust metal Concentration, (Turekian and Wedepohl, 1961)
Assessment of the subsoil trace elements based on Geoaccumulation Index (I-geo) and Pollution Load Index
The results of the Igeo index for some selected high priority trace elements are presented in Table 5. These elements include Cu, Pb, Zn, Ni, Co, Mn, As, Th, Sr, Cd, V, U, La and Cr. From the results, it was observed that elements such as Pb, Th, Sr, Cd, As U and La, practically showed negative Igeo values which suggests that the subsoil are practically unpolluted with respect to these elements. Cu Igeo values fall within the range of “unpolluted” in more than 60% of the studied locations, while about 30% of the locations are uncontaminated to moderately contaminated. The remaining 10% of the sample locations are moderately contaminated. Mn Igeo values were found to range from uncontaminated to moderately contaminated. However, locations that were uncontaminated are found to be significantly (about 60%) higher than the sample locations (about 40%) that were moderately contaminated. Similar trend were observed for V and Cr, with much of the sample locations exhibiting uncontaminated to moderately uncontaminated. Generally, it was observed that the Igeo index values of the selected trace elements in the subsoil samples were essentially uncontaminated.
Similarly, the results for the Contamination Factor (CF), are presented in Table 6. From the result, as earlier explained in the methodology, it was observed that Cu in the subsoil recorded low to moderate contamination, which ranged from 0 to < 3. Pb, Zn, Ni, U, Th, La and Sr showed essentially low contamination of (CF <1). However, Co, Mn and Cr showed relatively higher CF values of >3 but < 6, suggesting considerable contamination in many of the locations sampled. The high CF values of Mn, Co and Cr may not be unconnected with the Mn-Oxides presence in the in-situ weathered lateritic soils from the granite gneiss that essentially underlain the study area. It could also be due to the scavenging action of Mn-oxides on these elements in the secondary environment. The result of the calculated Pollution Load Index, (PLI), as presented in Table 6, showed most of the sampled locations are not polluted except in locations 15, 18, 19 and 21 where their PLI is higher than 1. This may probably be attributed to mineralisation rather than pollution.
Table 5
Geo Accumulation Index results of trace elements in the subsoil in the study area
Sample
|
Ig Cu
|
IgPb
|
Ig Zn
|
Ig Ni
|
IgCo
|
IgMn
|
Ig As
|
IgU
|
Ig Th
|
Ig Sr
|
Ig Cd
|
Ig V
|
Ig La
|
Ig Cr
|
IDS001
|
0.6
|
-1.1
|
0.1
|
0.5
|
1.2
|
1.0
|
0.3
|
0.5
|
-1.9
|
-3.5
|
-0.2
|
0.9
|
-0.4
|
0.6
|
IDS002
|
0.3
|
-0.2
|
0.3
|
0.9
|
2.1
|
1.1
|
1.8
|
1.1
|
-0.8
|
-3.3
|
-0.2
|
2.4
|
-0.7
|
1.6
|
IDS003
|
1.6
|
-0.8
|
-0.4
|
0.5
|
2.5
|
1.7
|
1.1
|
0.5
|
-1.3
|
-3.7
|
0.1
|
2.4
|
-1.2
|
3.4
|
IDS004
|
2.1
|
-0.4
|
0.0
|
1.0
|
2.4
|
2.2
|
0.3
|
0.2
|
-1.5
|
-3.0
|
-0.2
|
1.1
|
0.3
|
1.3
|
IDS005
|
1.2
|
-0.5
|
1.1
|
0.9
|
1.8
|
2.0
|
0.8
|
0.7
|
-1.0
|
-3.2
|
-0.2
|
1.1
|
0.4
|
0.7
|
IDS006
|
1.6
|
-0.3
|
-0.1
|
1.2
|
2.7
|
2.3
|
0.6
|
0.5
|
-1.4
|
-3.3
|
0.3
|
1.1
|
-0.1
|
1.1
|
IDS007
|
0.0
|
-0.9
|
0.3
|
1.6
|
2.5
|
1.4
|
0.3
|
1.2
|
-0.6
|
-2.8
|
-2.7
|
2.2
|
-0.3
|
1.3
|
IDS008
|
1.7
|
-0.9
|
-0.3
|
1.2
|
3.0
|
2.6
|
-0.4
|
0.6
|
-2.0
|
-3.2
|
0.7
|
1.6
|
-0.7
|
1.8
|
IDS009
|
0.9
|
-0.9
|
0.8
|
0.9
|
1.7
|
1.4
|
-0.2
|
0.7
|
-1.2
|
-3.5
|
-0.2
|
1.0
|
0.1
|
0.8
|
IDS010
|
1.8
|
-0.7
|
0.6
|
1.2
|
2.2
|
1.9
|
1.1
|
0.1
|
-2.0
|
-2.1
|
0.1
|
1.8
|
-0.2
|
1.7
|
IDS011
|
2.0
|
-0.8
|
-0.2
|
0.5
|
0.8
|
0.9
|
0.1
|
0.6
|
-1.4
|
-3.6
|
-1.2
|
0.9
|
-0.6
|
0.9
|
IDS012
|
2.3
|
-0.8
|
1.0
|
0.7
|
2.0
|
2.5
|
0.3
|
0.2
|
-2.0
|
-2.9
|
1.0
|
0.7
|
-0.1
|
0.6
|
IDS013
|
0.0
|
-1.0
|
0.2
|
1.6
|
2.6
|
1.9
|
0.6
|
1.0
|
-1.3
|
-3.2
|
0.1
|
1.8
|
-0.3
|
1.6
|
IDS014
|
0.4
|
-1.2
|
0.0
|
1.6
|
1.7
|
0.3
|
0.1
|
1.0
|
-1.1
|
-2.8
|
-1.7
|
2.2
|
-0.2
|
2.5
|
IDS015
|
1.5
|
-0.6
|
0.1
|
0.5
|
2.0
|
1.8
|
0.6
|
0.2
|
-1.3
|
-3.5
|
-0.7
|
1.0
|
0.4
|
1.4
|
IDS016
|
-0.7
|
-1.3
|
-0.3
|
0.1
|
-0.1
|
-2.0
|
-2.7
|
-0.4
|
-1.9
|
-3.8
|
-2.7
|
1.0
|
-0.7
|
0.7
|
IDS017
|
2.0
|
-0.9
|
0.3
|
1.1
|
2.4
|
2.2
|
0.1
|
0.2
|
-2.2
|
-1.9
|
1.0
|
0.8
|
-0.6
|
0.6
|
IDS018
|
1.9
|
-0.8
|
1.6
|
1.3
|
2.6
|
2.9
|
0.4
|
0.9
|
-1.0
|
-2.9
|
1.5
|
0.9
|
1.3
|
0.7
|
IDS019
|
0.2
|
-1.2
|
-1.1
|
0.0
|
1.8
|
1.0
|
-1.2
|
0.5
|
-1.8
|
-3.2
|
-0.4
|
0.7
|
-1.1
|
0.2
|
IDS020
|
2.2
|
-0.4
|
0.8
|
1.5
|
2.9
|
2.5
|
1.0
|
0.9
|
-1.3
|
-3.1
|
0.7
|
2.3
|
-0.7
|
3.3
|
IDS021
|
1.0
|
-0.5
|
0.8
|
1.3
|
1.9
|
1.5
|
0.8
|
0.8
|
-0.8
|
-2.9
|
-0.7
|
1.4
|
0.2
|
1.1
|
Table 6
Contamination Factor and Pollution Load Index Results of Trace Elements in the study area
Sample
|
Cu
|
Pb
|
Zn
|
Ni
|
Co
|
Mn
|
As
|
U
|
Th
|
Sr
|
Cd
|
V
|
La
|
Cr
|
PLI
|
IDS001
|
1.00
|
0.32
|
0.72
|
0.95
|
1.57
|
1.31
|
1.31
|
0.96
|
0.18
|
0.06
|
0.6
|
1.22
|
0.51
|
1.01
|
0.01
|
IDS002
|
0.84
|
0.60
|
0.81
|
1.26
|
2.86
|
1.46
|
1.46
|
1.46
|
0.39
|
0.07
|
0.6
|
3.40
|
0.42
|
2.01
|
0.08
|
IDS003
|
2.02
|
0.40
|
0.50
|
0.93
|
3.81
|
2.13
|
2.13
|
0.92
|
0.26
|
0.05
|
0.7
|
3.54
|
0.29
|
6.90
|
0.03
|
IDS004
|
2.78
|
0.51
|
0.65
|
1.34
|
3.61
|
3.08
|
3.08
|
0.77
|
0.24
|
0.08
|
0.6
|
1.46
|
0.83
|
1.67
|
0.09
|
IDS005
|
1.52
|
0.46
|
1.41
|
1.22
|
2.29
|
2.65
|
2.65
|
1.08
|
0.34
|
0.07
|
0.6
|
1.39
|
0.90
|
1.06
|
0.45
|
IDS006
|
1.96
|
0.56
|
0.60
|
1.53
|
4.24
|
3.17
|
3.17
|
0.92
|
0.25
|
0.07
|
0.8
|
1.39
|
0.64
|
1.47
|
0.09
|
IDS007
|
0.66
|
0.36
|
0.80
|
2.00
|
3.81
|
1.79
|
1.79
|
1.58
|
0.43
|
0.10
|
0.1
|
2.99
|
0.56
|
1.68
|
0.06
|
IDS008
|
2.17
|
0.36
|
0.55
|
1.49
|
5.36
|
3.93
|
3.93
|
1.00
|
0.17
|
0.07
|
1.1
|
2.04
|
0.40
|
2.27
|
0.04
|
IDS009
|
1.22
|
0.36
|
1.19
|
1.27
|
2.18
|
1.79
|
1.79
|
1.08
|
0.28
|
0.06
|
0.6
|
1.36
|
0.71
|
1.17
|
0.19
|
IDS010
|
2.25
|
0.41
|
0.99
|
1.55
|
3.03
|
2.47
|
2.47
|
0.73
|
0.17
|
0.16
|
0.7
|
2.28
|
0.60
|
2.24
|
0.01
|
IDS011
|
2.59
|
0.37
|
0.60
|
0.92
|
1.19
|
1.24
|
1.24
|
1.00
|
0.25
|
0.06
|
0.3
|
1.26
|
0.45
|
1.23
|
0.15
|
IDS012
|
3.33
|
0.38
|
1.29
|
1.07
|
2.74
|
3.76
|
3.76
|
0.77
|
0.16
|
0.09
|
1.3
|
1.05
|
0.63
|
1.02
|
0.17
|
IDS013
|
0.65
|
0.34
|
0.77
|
2.01
|
4.15
|
2.48
|
2.48
|
1.31
|
0.28
|
0.07
|
0.7
|
2.28
|
0.55
|
2.06
|
0.01
|
IDS014
|
0.89
|
0.29
|
0.69
|
2.08
|
2.18
|
0.81
|
0.81
|
1.31
|
0.31
|
0.09
|
0.2
|
3.03
|
0.59
|
3.73
|
0.09
|
IDS015
|
1.95
|
0.45
|
0.71
|
0.93
|
2.61
|
2.28
|
2.28
|
0.77
|
0.27
|
0.06
|
0.4
|
1.33
|
0.89
|
1.72
|
1.20
|
IDS016
|
0.40
|
0.27
|
0.52
|
0.71
|
0.63
|
0.17
|
0.17
|
0.50
|
0.18
|
0.05
|
0.1
|
1.29
|
0.40
|
1.11
|
0.01
|
IDS017
|
2.71
|
0.35
|
0.81
|
1.38
|
3.44
|
2.97
|
2.97
|
0.77
|
0.15
|
0.18
|
1.3
|
1.19
|
0.43
|
1.02
|
0.12
|
IDS018
|
2.42
|
0.39
|
2.08
|
1.62
|
4.03
|
4.84
|
4.84
|
1.23
|
0.34
|
0.09
|
1.9
|
1.26
|
1.62
|
1.11
|
1.30
|
IDS019
|
0.77
|
0.30
|
0.30
|
0.67
|
2.39
|
1.29
|
1.29
|
0.92
|
0.19
|
0.07
|
0.5
|
1.05
|
0.31
|
0.76
|
3.49
|
IDS020
|
3.17
|
0.52
|
1.17
|
1.84
|
5.03
|
3.80
|
3.80
|
1.23
|
0.27
|
0.08
|
1.1
|
3.30
|
0.40
|
6.36
|
0.10
|
IDS021
|
1.38
|
0.48
|
1.15
|
1.62
|
2.54
|
1.90
|
1.90
|
1.19
|
0.38
|
0.09
|
0.4
|
1.77
|
0.78
|
1.44
|
0.18
|
PLI = Pollution load Index