Preliminary assessment of microbial mats in seawater metal remediation

MORALES PONTET, NATALIA GABRIELA; FERNÁNDEZ, CAROLINA; PERILLO, VANESA LILIANA; LA COLLA, NOELIA SOLEDAD; SERRA, ANALÍA VERÓNICA; BOTTÉ, SANDRA ELIZABETH

ENVIRONMENTAL MONITORING AND ASSESSMENT

SPRINGER

Año: 2023 vol. 195 p. 195 - 516

0167-6369

Microbial mats have a special role in theremoval of metals in marine environment. This studyaimed to experimentally determine the efficiency ofCr removal from seawater by microbial mats. Theeffect of Cr on the microphytobenthic community andthe influence of an aerated condition on the removalof metal and microorganisms were also considered.Hence, microbial mat samples were subdivided in 4groups: submerged in Cr (chromium 2 mg/L withoutaeration), Cr + O2(chromium 2 mg/L with aeration),SW + O2(filtered seawater with aeration), and a control:SW (filtered seawater with neither chromium noraeration). Water and microbial mat subsamples wereused to determine Cr concentrations, organic mattercontent, granulometry, physicochemical parameters,chlorophyll a, phaeopigments, and quantitative analysisof the microphytobenthic community. Cr removalefficiency from seawater was 95% for the Cr treatmentand 99% for the Cr + O2treatment. The abundanceof cyanobacteria tended to decrease betweenthe initial and final days of the assay, whereas theopposite trend was observed for diatoms. Two aspectsare worth noting in the paper: microbial mats efficientlyremoved Cr from seawater at a concentrationof 2 mg Cr/L and the removal of Cr by microbialmats was more efficient with water aeration.