Inactivation of Faecal Coli form Indicator Microorganisms in A Constructed Wetland Under Diverse Environmental Conditions
This study was aimed to eradicate the fecal coliform (FC) from rural sewage by horizontal subsurface flow constructed wetland under different environmental conditions including temperature, pH and dissolved oxygen (DO). Three horizontal sub-surface flow constructed wetlands (HSSF-CW); two lined with either limestone (HSSF-CW-LS) or sawdust, HSSF-CW-SD) substrates and one planted with Iris pseudacorus (HSSF-CW-IP). The FC received in CW inflow ranged from 85 to 54 CFU/100 mL. The removal efficiency was found to be influenced by temperature, dissolved oxygen (DO) and pH. Cumulative data of treated wastewater depicted that the HSSF-CW-IP achieved the highest performance in the FC reduction with average removal efficiency of 82%. Whereas, HSSF-CW-SD and HSSF-CW-LS exhibited slightly lower results being 81 and 79%, respectively. This study highlighted the potential of HSSF-CW with respect to removal of fecal coliform from the wastewater to safeguard the public health from water-borne diseases.
Index Terms — Constructed wetland; Wastewater; Faecal coliform; Dissolved oxygen.