دراسة التغايرات الفصلية لمياه المصب العام و بعض المبازل الشمالية الرافدة فيه

الملخص EN

Our study was aimed to assess seasonal variation of Main Outfall Drain and: Al-Es'haky, Sabe'e Al-Bor, Al-Saglawia and Al-Shuala trocars using several physical and chemical variables, water samples were collected from the surface about 10-15 cm in depth from these sites from February 2010 to January 2011.

The results show that the mean of temperature was significantly (P ≥ 0.05) affected by seasonal temperature and seemed to be lowered during winter (13.26 ± 2.6 to 14.3 ± 1.9) and was high in summer ( 22.6 ± 2.6 to 23.9 ± 1.2 ) but un affected (P≤0.05) by water collecting sites.

For pH values, the obtained results seem to be almost not acidic and also not significantly influenced by either the climate seasons or by collection sites and found to range from 7.8 ± 0.2 to 8.8 ± 0.3.

However, similar findings were recorded for electric conductivity where again insignificant impacts (P ≥ 0.05) of both climate seasons and collecting sites and mean values varied from 188.0 ± 0.0 to 2380.3 ± 10.0 μS/cm.

Mean dissolved salt content was found to be significantly affected (P ≥ 0.05) by collecting sites but not by climate season and highest value (1260.0 ± 14.2 mg/l) was recorded in Al-Es'haky samples while the lowest value (1670.3 ± 30.0 mg/l) was in the Main Outfall Drain samples.

However, the mean dissolved oxygen content was in general high in winter, spring and autumn and relatively lower in summer and such data were insignificantly differed (P ≤ 0.05) from each other in case of climate season but were very significant (P ≥ 0.05) in case of collecting sites.

Al-Shuala samples had the lowest values (6.0 ± 0.4 to 8.0 ±0.2 mg/l) while Main Outfall Drain sample showed highest (8.4 ± 0.0 to 9.0 ± 0.1 mg/l) values.

For oxygen saturated percentage, it was found that the mean value was not significantly (P ≤ 0.05) affected by both clime season and collecting sites except for Al-Shuala samples which was significantly (P ≥ 0.05) different.

Similar findings were found for BOD mean values where the recorded data were again insignificantly (P ≤ 0.05) influenced by both climate season and collecting sites except Sbe'e Al-Bor trocar which had the significantly (P ≥ 0.05) lowest values ranging from 1.3 ± 0.3 mg/l in winter to 2.6 ± 0.3 mg/l in summer.