Role of Microorganisms in the Remediation of Wastewater in Floating Treatment Wetlands: A Review

This article provides useful information for understanding the specific role of microbes
in the pollutant removal process in floating treatment wetlands (FTWs). The current literature
is collected and organized to provide an insight into the specific role of microbes toward plants
and pollutants. Several aspects are discussed, such as important components of FTWs, common
bacterial species, rhizospheric and endophytes bacteria, and their specific role in the pollutant removal
process. The roots of plants release oxygen and exudates, which act as a substrate for microbial
growth. The bacteria attach themselves to the roots and form biofilms to get nutrients from the plants.
Along the plants, the microbial community also influences the performance of FTWs. The bacterial
community contributes to the removal of nitrogen, phosphorus, toxic metals, hydrocarbon, and
organic compounds. Plant–microbe interaction breaks down complex compounds into simple
nutrients, mobilizes metal ions, and increases the uptake of pollutants by plants. The inoculation of
the roots of plants with acclimatized microbes may improve the phytoremediation potential of FTWs.
The bacteria also encourage plant growth and the bioavailability of toxic pollutants and can alleviate
metal toxicity.