Abstract

As part of the study of agricultural reuse of treated wastewater and its effect on irrigated plants. An investigation took place in the Sedrata area (Souk-Ahras), a typical region belonging to a large perimeter mainly irrigated by the Oued Charef dam, which is supplied by the treated wastewaters of Sedrata sewage plant, in order to diagnose its quality and suitability for irrigation during two different periods (rainy winter and dry autumn). The radish (Raphanus sativus L.) was chosen as a study model.
The physicochemical and microbiological diagnosis carried out on the three water sampling sites in this region (at the exit of the ST-EP (W1) and after joining their natural environment: Oued Charef (W2), and its dam (W3)) indicates that these waters are of a predominantly ‘domestic’ character with reduced contamination by heavy metals, and the absence of highly acidic or alkaline discharges. On the other hand, they represent a fairly significant risk of salinity, particularly the waters of the Oued Charef dam (W3).
By evaluating the suitability of water from the sites for irrigation (according to IWQI quality indices), it can be seen that the classification of treated water in this region and its suitability for use can vary from one period to another. Overall, they are considered reusable according to the SAR, CROSS, IP, MH, and RSBC indices. However, in terms of PS, KR and TH, they are considered unsuitable for agricultural irrigation, particularly during the dry autumn period. This makes their permanent reuse require more caution and special attention.
To highlight the effect of these waters on the soil, we observed a dubious increase in the risk of sodicity, particularly for ST-EP waters (W1), although this study was spread over a short period (five ‘05’ weeks).”
The treated wastewater at the exit of the Sedrata ST-EP (W1) generally meets the required standards for reuse. This is well observed through the germination and growth indices of radish seedlings, which show a stimulating effect of this type of water, as opposed to saline dam waters, which have a rather negative effect. Similarly, due to their richness in nutrients, treated wastewater (W1) and Oued Charef water (W2) have favored good growth and a good yield (quantitative and qualitative) of this root vegetable (Raphanus sativus L.).
The bacteriological analysis also indicates that the level of contamination of radish crops by coliforms, streptococci, and Escherichia coli is far from being infectious after ingestion and admissible for commercialization.
For the study of the effect of these waters on a biochemical scale and the oxidant-antioxidant system in radish under semi-controlled conditions. The treated waters revealed a stressful effect translated by a reduction in chlorophyll pigments and total proteins, as well as an increase in hydrogen peroxide. Plants react to this stress by increasing the synthesis of reduced glutathione, the activity of glutathione peroxidase, ascorbate peroxidase, and glutathione-S-transferase.

Keywords: Treated wastewater, irrigation, Quality indices, Sewage plant, Sedrata, Oued Charef dam, radish, Oxidative stress.

Information

Item Type:	Thesis
Divisions:	» Faculty of Natural Sciences and Life
ePrint ID:	4893
Date Deposited:	2024-02-26
Further Information:	Google Scholar
URI:	https://www.univ-soukahras.dz/en/publication/article/4893

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