Marwa Ben Saad PhD on macrophyte filters to improve water quality

Marwa Ben Saad establish her practical stay in the MSMLab laboratory of the UNESCO Chair in Sustainability. The past April 11 she read her doctoral thesis at the Institut National Agronomique de Tunisia.

Barcelona, September 14


The research topic fits into the context of a sustainable management of unconventional water resources.  


The main objective is to present innovative solutions in order to improve the wastewater treatment system by filters planted with macrophytes. The present study conducted on the laboratory scale, was focused mainly on the removal of nitrates and pathogens from wastewater, based on the bioinoculation of bacteria and bacteriophages in the filters.


The screening of the bacteria made selecting a bacterial strain having a great ability to assimilate nitrates and its inoculation in the rhizosphere in the filters, showed an improvement of nitrates elimination. In the same way, the bioinoculation of the antagonistic bacteria or bacteriophages improves significantly the inactivation of pathogenic bacteria. Using of cork as filling material for planted filters has shown better reduction of nitrates (80% to 90%), compared to gravel (4 to 70%). Cork seems to be a good support for developing denitrifying bacteria, this result is confirmed by molecular study. The use of cork and the bioinoculation of denitrifying bacteria leads to the total elimination of nitrates (100%).


Link to Download Thesis