Traitement biologique des eaux usées par les Macrophytes et effet de leur réutilisation sur la culture de l’aubergine (Solanum Melongena L.).

Abstract

Algeria is facing a constant increase in water scarcity, a phenomenon exacerbated by growing demand and shortages due to climate variations. This critical situation has imposed the urgent need to implement solutions for wastewater treatment. It is in this context that this study focuses on the exploitation of macrophyte plants, particularly reeds, as a wastewater treatment system aimed at supporting plant production. The experimental setup relies on three tanks, each containing 100 liters of gravel covered with a 40 cm thick layer of soil composed of silt, clay, and sand. These tanks serve as a growing medium for young reed shoots, at maximum density. The results of physico-chemical analyses and the purifying performance of the reed system are remarkable. They demonstrate a particularly effective removal capacity of organic load, with significant reduction rates: 97.33% for suspended solids (MES), 83.05% for chemical oxygen demand (COD), 96.5% for biochemical oxygen demand (BOD5), and a stable pH at 7.75. These values are in complete compliance with irrigation standards established by the World Health Organization (WHO) and current national regulations. The results obtained confirm the overall effectiveness of the reed-based wastewater treatment system, and highlight a substantial improvement in the development of eggplant crops. Thus, this study underscores the considerable advantages of using macrophyte plants, specifically reeds, in wastewater treatment and their beneficial integration into plant production.