{"title":"Evaluation of the efficiency of wastewater treatment and the diversity of phytoplankton in a large-scale waste stabilization pond in an arid climate","authors":"Aafaf Krimech , Sofyan Sbahi , Naaila Ouazzani , Brahim Oudra , Ouafa Cherifi , Laila Mandi","doi":"10.1016/j.ecoleng.2025.107518","DOIUrl":null,"url":null,"abstract":"<div><div>This study aimed to evaluate the effectiveness of a full-scale waste stabilization pond in treating domestic wastewater in a peri-urban area with arid climatic conditions. The experiment was conducted in the municipality of Saada, located 18 km west of Marrakech, Morocco. The wastewater treatment system consisted of two anaerobic ponds, four facultative ponds, and four maturation ponds arranged in series. The system treated an average inflow of 525 m<sup>3</sup>/day. In order to evaluate the efficiency of the treatment process, periodic sampling and analysis of physicochemical and bacteriological parameters were performed at the influent and effluent of each treatment stage. Phytoplankton monitoring was carried out in the three lagoons (anaerobic, facultative and maturation). The study found that maximum pollutant removal occurred during the warmer months of the year, and minimum removal occurred during the winter period. The highest removal percentages of TSS, COD, and NH<sub>4</sub><sup>+</sup> were 72.66 %, 79.28 %, and 72.53 %, respectively. However, the removal of total phosphorus and its assimilable form (PO<sub>4</sub><sup>3−</sup>) did not exceed 40 % and 50 %, respectively. Fecal coliform removal reached an average removal of 2.71 log units at the outlet of the maturation pond. Phytoplankton parameters, based on qualitative and quantitative aspects of microalgae, indicated a dominance of cyanobacteria (46.87 %) and chlorophyceae (28.13 %), while diatoms were moderately present (12.50 %) in all ponds. This may indicate an unsatisfactory purification performance of the plant. The quantitative study also showed a great dominance of the species <em>Chlorella</em>, especially in the maturation pond.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107518"},"PeriodicalIF":3.9000,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ecological Engineering","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0925857425000060","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study aimed to evaluate the effectiveness of a full-scale waste stabilization pond in treating domestic wastewater in a peri-urban area with arid climatic conditions. The experiment was conducted in the municipality of Saada, located 18 km west of Marrakech, Morocco. The wastewater treatment system consisted of two anaerobic ponds, four facultative ponds, and four maturation ponds arranged in series. The system treated an average inflow of 525 m3/day. In order to evaluate the efficiency of the treatment process, periodic sampling and analysis of physicochemical and bacteriological parameters were performed at the influent and effluent of each treatment stage. Phytoplankton monitoring was carried out in the three lagoons (anaerobic, facultative and maturation). The study found that maximum pollutant removal occurred during the warmer months of the year, and minimum removal occurred during the winter period. The highest removal percentages of TSS, COD, and NH4+ were 72.66 %, 79.28 %, and 72.53 %, respectively. However, the removal of total phosphorus and its assimilable form (PO43−) did not exceed 40 % and 50 %, respectively. Fecal coliform removal reached an average removal of 2.71 log units at the outlet of the maturation pond. Phytoplankton parameters, based on qualitative and quantitative aspects of microalgae, indicated a dominance of cyanobacteria (46.87 %) and chlorophyceae (28.13 %), while diatoms were moderately present (12.50 %) in all ponds. This may indicate an unsatisfactory purification performance of the plant. The quantitative study also showed a great dominance of the species Chlorella, especially in the maturation pond.
期刊介绍:
Ecological engineering has been defined as the design of ecosystems for the mutual benefit of humans and nature. The journal is meant for ecologists who, because of their research interests or occupation, are involved in designing, monitoring, or restoring ecosystems, and can serve as a bridge between ecologists and engineers.
Specific topics covered in the journal include: habitat reconstruction; ecotechnology; synthetic ecology; bioengineering; restoration ecology; ecology conservation; ecosystem rehabilitation; stream and river restoration; reclamation ecology; non-renewable resource conservation. Descriptions of specific applications of ecological engineering are acceptable only when situated within context of adding novelty to current research and emphasizing ecosystem restoration. We do not accept purely descriptive reports on ecosystem structures (such as vegetation surveys), purely physical assessment of materials that can be used for ecological restoration, small-model studies carried out in the laboratory or greenhouse with artificial (waste)water or crop studies, or case studies on conventional wastewater treatment and eutrophication that do not offer an ecosystem restoration approach within the paper.