Premium
Short‐term Effects of Gray Wastewater on a Mediterranean Sandy Soil
Author(s) -
Mekki Ali,
Fki Firas,
Kchaou Mariem,
Sayadi Sami
Publication year - 2015
Publication title -
clean – soil, air, water
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.444
H-Index - 66
eISSN - 1863-0669
pISSN - 1863-0650
DOI - 10.1002/clen.201400049
Subject(s) - wastewater , effluent , irrigation , sorghum , environmental science , germination , agronomy , sewage treatment , subsoil , pulp and paper industry , biology , environmental engineering , soil water , soil science , engineering
The treatment of urban wastewater has been significant progress along with the development of submerged biofiltration technology. Undeniably, the combination of biological processes to physical one was a promising alternative to treat wastewater. In this study, the main objective was the application of aerobic bed reactor in urban gray wastewater treatment. Afterward, treated wastewater effects on soil properties, on seeds germination, and on plants growth were investigated. Treated wastewater showed physico‐chemical and microbiological qualities that meet the required standards for reuse in irrigation. In fact, after 130 days of treatment, the average chemical oxygen demand removal reached 84%, the average five‐day biochemical oxygen demand removal attained 91% and the effluent pH was in the right range, varying between 7.3 and 7.8. Moreover, treated water was exempt from pathogenic germs as Salmonella , Staphylococcus , and Pseudomonas . The application of such treated water for irrigation of the soil and plants has significant results. Indeed, we noticed the improvement of soil water retention capacity by an average of 12%, soil organic matter content which increased by an average of 30%, and enhancement in soil microflora count by 80%. Besides, the germination indexes of tomato ( Lycopersicon esculentum ) and alfalfa ( Medicago sativa ) were increased by 30 and 50%, respectively, in soil irrigated by untreated and treated gray wastewater. Furthermore, better growth levels for tested plant species, wheat ( Triticum durum ), barley ( Hordeum vulgare ), and sorghum ( Sorghum bicolor ), were obtained in the presence of treated wastewater.