Journal of Environmental Health and Sustainable Development

en The Effect of Wastewater Irrigation on the Activity of Soil Microorganisms Water quality and wastewater treatment and reuse Original articles Introduction: The use of wastewater for irrigation in arid and semi-arid regions of the world is increasing. This study aimed to evaluate the effects of wastewater on the microbial activity of irrigated soils using the enzymatic activity of soil microorganisms. Materials and Methods: In this study, for soil irrigation, the secondary effluent of the Isfahan municipal wastewater treatment plant was used. As a control, tap water that has no microbial load was also used. Soil samples were collected in two stages, before and immediately after irrigation. All samples were collected in sterile bags, transferred immediately to the laboratory for physicochemical and microbiological tests. Soil samples were analyzed for the amounts of enzymatic activity (Fluorescein Diacetate (FDA) and dehydrogenase), electrical conductivity (EC), oxidation-reduction potential (ORP), and pH. Results: The EC levels before and after irrigation with tap water was 231.2 and 260.63 µs.cm-1, respectively, which was significantly different from levels of wastewater-irrigated soil (P < 0.05).  pH in the two types of used water before and after irrigation was 6-8 and 7-8, respectively. No significant difference was observed in the levels of FDA, dehydrogenase, ORP, and microbial population in samples irrigated with water and wastewaters (p > 0.05). It was found that there is a significant relationship between bacterial density and FDA (P < 0.05). <div style="text-align: justify;">Conclusion: The results of the study showed that irrigation with wastewater has no significant effect on the microbial activity of irrigated soil. Because of the short-term wastewater irrigation in the present study, however, further investigation is needed to evaluate the effect of long-term wastewater irrigation on the microbial and physicochemical quality of soil. <style type="text/css"> </style> <style type="text/css"><me<illegal tag>ta http-equiv=Content-Type content="text/html; charset=utf-8"><me<illegal tag>ta name=ProgId content=Word.Document><me<illegal tag>ta name=Generator content="Microsoft Word 14"><me<illegal tag>ta name=Originator content="Microsoft Word 14"> </style> <style type="text/css"> </style> <style type="text/css"><me<illegal tag>ta http-equiv=Content-Type content="text/html; charset=utf-8"><me<illegal tag>ta name=ProgId content=Word.Document><me<illegal tag>ta name=Generator content="Microsoft Word 14"><me<illegal tag>ta name=Originator content="Microsoft Word 14"> </style> <style type="text/css"> </style> </div> Enzymatic Activity, Fluorescein Diacetate, Microbial Population. 1399 1406 http://jehsd.ssu.ac.ir/browse.php?a_code=A-10-85-2&slc_lang=en&sid=1 Hossein Karimi h.karimi.m90@gmail.com 0000-0003-0005-6170 Yes Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Mahnaz Nikaeen mah.nikaeen@gmail.com 0000-0002-1852-1547 No Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Maryam Hatamzadeh 0000-0003-4767-1963 No Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Marzieh Vahid Dastjerdi 0000-0001-5807-8060 No Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Marzieh Farhadkhani 0000-0002-7282-5760 No Department of Environmental Health Engineering, Educational Development Center, Shahrekord University of Medical Sciences, Shahrekord, Iran.