International Journal of Marine Science 2016, Vol.6, No.58, 1-8
3
Total filtered volume of water (V) was calculated from the following equation (DeBernardi, 1984):
V = d r
2
π
Where:
d = the distance (m) travelled by net, which equals to 0.3 x numbers of the flow meter revolutions.
r = the net radius which equals to 0.2 m.
π = equal to 3.143.
The numbers of individuals were calculated in the sample diluted to 1000 ml in the manner prescribed by
American Public Health Association (2006), and expressed the result in cubic meter.
No./m
3
= (C X VI ) / ( V II X VIII )
Where:
C = the number of individuals in the subsample
VI = volume of sample (ml).
VII = the size of the subsample (10 ml).
V III = volume of water filtered in cubic meters
Identification of the species was done by utilizing various publications Brook (1959), Smirnov (1971, 1992 and
1996), Benzie (2005), Kotov and Stifter (2006).
Results
Physical and chemical parameters
Water temperatures at the three stations are convergent to each other; they ranged between 15–27.5 ºC in January
and July 2013 respectively. Salinity ranged from 1.8 psu at station 2 (Abu Al-Khasib) in winter, to 40 psu at
station 3 (Al-Faw) in summer, while the hydrogen ion concentration pH varied from 6.2–8.7 at station 3 (Al-Faw)
in spring and summer respectively. Whereas dissolved oxygen ranged from 5.1 mg/l at station 1 (Al-Ashar) in
summer, to 9.9 mg/l at station 2 (Abu Al-Khasib) in spring. As for the total dissolved solids (TDS) values were
ranging from 1467 mg/l at station 1 (Al-Ashar) in autumn, to 33590 mg/l, at station 3 (Al-Faw) in summer, While
the highest value of turbidity 180.6 FTU were encountered during winter at station 3 (Al-Faw), whereas the
lowest value 7.1 FTU were recorded during spring at station 1 (Al-Ashar), (Fig. 2, 3, 4).
Fig. 2 Water temperatures and Salinity at three stations in Shatt Al-Arab River during the study period.
