Abstract

The city of Souk Ahras (North-East Algeria) contains some of the waste water discharges that are not connected to the wastewater treatment plant. Residents discharge wastewater from multiple activities directly into the environment without treatment, improving the transmission of waterborne diseases.

This study aims first to determine the physico-chemical and microbiological characteristics of wastewater reused in irrigation of town from Souk Ahras. As a result, three sites for discharges discharged into the Medjerda Wadi during the irrigation period were selected: discharge 1: (Khmissa), discharge 2: (Hannancha) and discharge 3 (Souk Ahras town). In a second objective, we were interested in evaluating the purification performance of aquatic plants on the effectiveness of the purification of polluted water for the city of Souk Ahras under the effect of different residence times (7, 14 and 21 days). Finally, we evaluated the resistance of these aquatic plants by measurements of physiological, biochemical, enzymatic and non-enzymatic parameters and the histological study was also included.

Analyses carried out from the march to august 2016 irrigation period revealed organic pollution resulting in high BOD5 and COD of up to 170.25 ± 32.34 mg/l O2 and 286.73 ± 39.65 respectively mg/l O2 in discharge 1, at site 2 is in the order of 142.38 ± 84.11 mg/l O2 for BOD5, and 358.9 ± 32.81 mg/l O2 for COD and at discharge 3 is in the order of 148

± 25.11 mg/l O2 for BOD5, and 333.85 ± 42.12 mg/l O2 for COD.

The average ratio COD/ BOD5 is of the order of 0.58 for discharge of Khmissa, 0.73 for discharge of Hannancha and 0.45 for discharge Souk Ahras town.

These results lead the conclusion that the three sewage sites are polluted by organic pollution which is characterized by partially degradable. This result leads to the conclusion that Medjerda wadi receives wastewater characterized by significant organic pollution. Our results also show the presence of toxic bacteria, parasites of helminth eggs and yeasts, which pose a health risk to farmers and consumers.

The statistical application of the PCA to twenty of the variables studied revealed that the Medjerda Wadi receives raw wastewater of a domestic nature and should not be reused directly in irrigation before being subjected to prior treatment in order to improve their quality by meeting the required standards.

The efficiency of the phyto-purification by Typha latifolia process applied in wastewater treatment under the effect of residence time is confirmed by the abatement results found: 92.66% for COD, 90.1% for BOD5, 97.6% for TSS, 96% for Cr and 95% for Co. Concerning the parasitic load, the three stressed planted tanks ensure a total elimination of parasitic helminth eggs.

The results also showed disturbances in the physiological response of Typha latifolia in the three polluted planted tanks. These results translate into reduced chlorophyll activity, as well as for biochemical responses, we obtained an increase in total protein and total sugar.

Concerning the enzymatic parameters our results recorded a strong activation of antioxidant enzymes (APX, CAT), for the non-enzymatic parameters, our results also showed an increase in MDA and GSH levels of Typha latifolia in leaves and roots.

The study of the anatomy of the roots of Typha latifolia shows the existence of different anomalies in the samples taken from the planted tank 3 compared to those taken from the control samples.

Keywords: Souk Ahras, wastewater, PCA, Typha latifolia, pollution.

Information

Item Type:	Thesis
Divisions:	» Laboratory for Terrestrial and Aquatic Ecosystems » Faculty of Natural Sciences and Life
ePrint ID:	2133
Date Deposited:	2020-03-09
Further Information:	Google Scholar
URI:	https://www.univ-soukahras.dz/en/publication/article/2133

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