Introduction
Materials and methods
Study area
Sampling
Laboratory analysis
Assessment of sediment contamination
Contamination factor (Cf)
Modified degree of contamination (mCd)
Tomlinson pollution load index (PLI)
Enrichment factor (EF)
Geo-accumulation index (Igeo)
Statistical analysis
Results and discussion
Do the physicochemical properties of Butuah Lagoon fall within the accepted range for aquatic life?
Sample Period | pH | TDS (mg/L) | COND (µS/cm) | TEMP (°C) | COD (mg/L) | BOD (mg/L) | Oil & G (mg/L) | Chlor (mg/L) |
---|---|---|---|---|---|---|---|---|
December | ||||||||
W1 | 8.2 | 1961.3 | 3922.3 | 30.7 | 383.0 | 120.3 | 10.7 | 7092.7 |
W2 | 8.3 | 1903.3 | 3805.3 | 31.0 | 136.7 | 45.7 | 13.3 | 5646.3 |
W3 | 7.5 | 141.7 | 283.0 | 29.3 | 180.3 | 65.7 | 70.0 | 2449.0 |
January | ||||||||
W1 | 8.3 | 1960.3 | 3920.0 | 31.0 | 386.0 | 123.3 | 12.5 | 7097.7 |
W2 | 8.3 | 1904.7 | 3809.7 | 31.3 | 137.7 | 45.0 | 13.7 | 5649.3 |
W3 | 7.6 | 142.3 | 285.0 | 29.3 | 181.7 | 66.7 | 71.7 | 2449.7 |
February | ||||||||
W1 | 8.5 | 1956.0 | 3912.3 | 29.0 | 392.3 | 131.0 | 10.3 | 7100.3 |
W2 | 8.7 | 1902.0 | 3803.7 | 30.0 | 142.3 | 53.3 | 11.3 | 5649.7 |
W3 | 8.1 | 140.7 | 281.3 | 29.5 | 192.7 | 69.0 | 70.3 | 2447.3 |
March | ||||||||
W1 | 8.3 | 1953.0 | 3906.0 | 29.5 | 405.0 | 127.0 | 11.7 | 7104.7 |
W2 | 8.5 | 1899.7 | 3799.3 | 30.3 | 141.3 | 50.7 | 14.0 | 5652.7 |
W3 | 8.0 | 140.3 | 279.7 | 29.7 | 194.7 | 68.7 | 68.0 | 2448.3 |
Mean | 8.2 | 1333.8 | 2667.3 | 30.1 | 239.5 | 80.5 | 31.5 | 5065.6 |
TDS | pH | COND | TEMP | COD | BOD | Chlor | Oil & G | |
---|---|---|---|---|---|---|---|---|
TDS | 1.000 | |||||||
PH | 0.078 | 1.000 | ||||||
COND |
1.000
| 0.078 | 1.000 | |||||
TEMP |
0.511
| −0.122 |
0.511
| 1.000 | ||||
COD |
0.362
| 0.195 |
0.362
| −0.139 | 1.000 | |||
BOD | 0.306 | 0.176 | 0.306 | −0.211 |
0.995
| 1.000 | ||
Chlor |
0.960
| 0.123 |
0.960
|
0.398
|
0.607
|
0.558
| 1.000 | |
Oil & G | −0.998
| −0.079 |
−0.998
| −0.503
| −0.362
| −0.306 | −0.958
| 1.000 |
What is the level of Cd, Pb, As, Zn, Fe, Hg, and Cu in water, sediment and fish samples from Butuah Lagoon?
Cadmium (Cd)
Element | Medium | Concentration (mg/kg and mg/L respectively) |
F
|
p
| ||
---|---|---|---|---|---|---|
Downstream | Midstream | Upstream | ||||
As | Sediment | 94 ± 6 | 94 ± 3 | 67 ± 3 | 24 |
0.001
|
Fe | Sediment | 1517 ± 101 | 1771 ± 49 | 1839 ± 59 | 3 | 0.094 |
Water | 0.83 ± 0.20 | 0.28 ± 0.03 | 1.27 ± 0.17 | 36 |
0.001
| |
Cu | Sediment | 18.6 ± 8.5 | 60.6 ± 4.7 | 5.8 ± 0.6 | 85 |
0.001
|
Water | 0.04 ± 0.01 | 0.04 ± 0.01 | 0.033 ± 0.006 | 49 |
0.001
| |
Zn | Sediment | 146.3 ± 93.3 | 228.8 ± 74.8 | 35.1 ± 35.3 | 16 |
0.004
|
Water | 0.30 ± 12.00 | 0.15 ± 0.03 | 0.20 ± 0.32 | 2 | 0.181 | |
Pb | Sediment | 32.7 ± 13.0 | 77.8 ± 5.7 | 7.6 ± 1.7 | 62 |
0.001
|
Water | 0.29 ± 0.03 | 0.28 ± 0.29 | 0.17 ± 0.02 | 60 |
0.001
| |
Cd | Sediment | 3.7 ± 1.9 | 7.7 ± 1.8 | 3.7 ± 3.8 | 2 | 0.142 |
Water | 0.037 ± 0.010 | 0.037 ± 0.01 | 0.22 ± 0.005 | 7 |
0.002
| |
Hg | Sediment | 0.004 ± 0.007 | 0.148 ± 0.008 | 0.005 ± 0.008 | – | – |
Element | Medium | Mean concentration difference ± Standard error | ||
---|---|---|---|---|
S1–S2 | S1–S3 | S2–S3 | ||
As | Sediment | 0.267 ± 4.5 |
27.4 ± 4.5
|
27.1 ± 4.5
|
Fe | Sediment | −253.3 ± 126.4 | −322.0 ± 126.4 | −68.4 ± 126.4 |
Water |
0.55 ± 0.1
| −0.437 ± 0.1
| −0.987 ± 0.1
| |
Cu | Sediment | −42.1 ± 4.4
| 12.7 ± 4.4 |
54.8 ± 4.4
|
Water | 0.002 ± 0.001 |
0.011 ± 0.001
|
0.009 ± 0.001
| |
Zn | Sediment | −82.6 ± 34.8 | 111.2 ± 34.8 |
193.8 ± 34.8
|
Water | 0.144 ± 0.077 | 0.094 ± 0.077 | −0.050 ± 0.077 | |
Pb | Sediment | −45.1 ± 6.4
|
25.1 ± 6.4
|
70.2 ± 6,4
|
Water | 0.009 ± 0.012 |
0.122 ± 0.012
|
0.113 ± 0.012
| |
Cd | Sediment | −4.0 ± 2.1 | -0.7 ± 2.1 | 4.0 ± 2.1 |
Water | 0.000 ± 0.004 |
0.015 ± 0.004
|
0.015 ± 0.004
|
Lead (Pb)
Arsenic (As)
Zinc (Zn)
Iron (Fe)
Mercury (Hg)
What is the degree of heavy metal pollution in the sediment as indicated by assessment index?
Enrichment factor (EF)
Station | Enrichment factor | |||||
---|---|---|---|---|---|---|
As | Cu | Zn | Pb | Cd | Hg | |
Downstream | 650.08 | 22.01 | 72.51 | 63.80 | 1347.21 | 2.82 |
Midstream | 555.48 | 61.65 | 97.23 | 130.22 | 2424.88 | 8.40 |
Upstream | 379.84 | 5.68 | 14.34 | 12.20 | 1131.67 | 2.60 |
Mean in the lagoon | 528.47 | 29.78 | 61.36 | 68.74 | 1634.59 | 4.61 |
Contamination factor, degree of contamination and PLI
Station | Contamination factor | C
d
|
mC
d
| PLI | ||||||
---|---|---|---|---|---|---|---|---|---|---|
As | Fe | Cu | Zn | Pb | Cd | Hg | ||||
Downstream | 19.57 | 0.03 | 0.66 | 2.18 | 1.92 | 40.56 | 0.09 | 65.01 | 9.29 | 1.28 |
Midstream | 19.51 | 0.04 | 2.17 | 3.42 | 4.57 | 85.19 | 0.30 | 115.20 | 16.46 | 2.48 |
Upstream | 13.86 | 0.04 | 0.21 | 0.52 | 0.45 | 41.30 | 0.10 | 56.48 | 8.07 | 0.72 |
Mean in the lagoon | 17.65 | 0.04 | 1.01 | 2.04 | 2.31 | 55.68 | 0.16 | 78.90 | 11.27 | 1.49 |
Geo-accumulation index
Station | Geo-accumulation index (I
geo) | ||||||
---|---|---|---|---|---|---|---|
As | Fe | Cu | Zn | Pb | Cd | Hg | |
Downstream | 3.71 | −5.64 | −1.18 | 0.54 | 0.36 | 4.76 | −4.14 |
Midstream | 3.70 | −5.42 | 0.53 | 1.19 | 1.61 | 5.83 | −2.35 |
Upstream | 3.21 | −5.36 | −2.85 | −1.52 | −1.75 | 4.78 | −3.98 |
Mean in the lagoon | 3.54 | −5.47 | −1.17 | 0.07 | 0.07 | 5.12 | −3.49 |