International Journal of Aquaculture, 2018, Vol.8, No.4, 23-28
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Table 1 High concentrations of metals in the water samples obtained from three stations (Rivers) located in Al-Qurna city, Basrah,
Iraq (
p
<0.05)
Sampling stations
Iron
Lead
Copper
Zinc
St. 1
0.24±0.036
0.012±0.003
0.11±0.001
1.25±0.022
St. 2
0.35±0.044
0.022±0.002
0.10±0.001
1.29±0.00
St. 3
0.28±0.023
0.010±0.003
0.18±0.002
1.22±0.016
The results in Table 1 showed there is no significant change in concentration all of iron, lead and zinc in stations 1,
3 in Al-Qurna city. However, at station 2, there is change in concentration of iron, lead, zinc may be due to
increased rate of non-treatment industrial waste which discharged to river. These results were agreed with
Baudizsova (1997). In case of concentrations of copper there is an increase at station 3 that is due to the flow of
the materials from upper regions of the river direct drainage from farmlands, sewage disposal plants. There is
slight increase in concentration of iron between three sites due to the anthropogenic activities such as agricultural
runoff, urbanization and industrialization.
2.2 Frequency of occurrence of the bacterial isolates
The most bacterial isolates belong to four genera:
Pseudomonas
,
Enterobacter
,
Escherichia
and
Staphylococcus
.
A total of 80 samples were collected from three stations in three rivers at Al-Qurna city during study period from
14
th
November 2016 to 18
th
April 2017, (20 from each station). After a careful experimental work St. 1 stand top
for having most number of coliforms found in drinking water samples with 19 samples (23.75%) followed by St. 2
were total no of coliform identified were in 16 samples (20.00%) and in St. 3 bacterial species were found in 13
samples (16.25%), as shown in Table 2.
Table 2 Total no of infected samples reported monthly
Nov-16
December
Jan-17
February
Total samples
Station 1
3
4
5
7
18
Station 2
4
2
4
4
16
Station 3
0
3
5
5
13
Four Bacterial species were found (
E. coli
,
P. aeruginosa
,
E. aerogenes
and
S. aureus
) in St. 1.
E. coli
was mostly
present specie and it was identified in 26 samples (32.50%) followed by
S. aureus
in 16 samples (20.00%),
P.
aeruginosa
in 10 samples (12.50%) and
E. aerogenes
in 7 samples (8.75%) as shown in Table 3.
Table 3 Total no of microorganisms found per month
Nov-16
December
Jan-17
February
Total samples
Total samples collected
20
20
20
20
80
Total Infected samples
15
14
12
18
58
E. coli
7
5
4
10
26
P. aeruginosa
3
3
1
3
10
E. aerogenes
1
2
4
0
7
S. aureus
4
4
3
5
16
According to Stevens et al. (2003),
E. coli
is main indicator for fecal contamination. Jay (1996) stated that
E. coli
presence is indication of enteric pathogens. According to Baudart et al. (2002), water quality is directly
proportional to presence of coliforms in water. According to Baudizsova (1997),
E. coli
should be used as a prime
bacteria as indicator for pathogenic contamination of water.
2.3 Biochemical tests
The different species of bacteria were identified using the biochemical tests namely, Motility test, Indole test,
Methyl red test, Voges-proskauer test, Citrate utilization test, Catalase test, Oxidase test, Triple sugar Iron test,
Urease test and Nitrate test. Broth cultures were observed the colour formation, ring formation and gas production,
