Reflectance and Chlorophyll Fluorescence of aquatic macrophytes as bioindicators for arsenic presence

ANALIA IRIEL; GAVIN DUNDAS; AICIA FERNÁNDEZ CIRELLI; MARÍA GABRIELA LAGORIO

Buenso Aires

Congreso; 5th International Congress on Arsenic in the Environment (As2014); 2014

CNEA

Non-destructive monitoring methodologies, sensitive to arsenic presence in the environment and able to perform a rapid screening of large polluted areas, are highly sought-after. Both chlorophyll-a fluorescence and reflectance of macrophytes may be potential indicators to sense toxicity in water media. In this work, the effects of arsenic on the optical and photophysical properties of leaves of different aquatic plants (Vallisneria gigantea, Azolla filiculoides and Lemna minor) were evaluated. Reflectance spectra were recorded for the plant leaves from 300 to 2400 nm. Initial fluorescence was recorded at low photon flux as a function of wavelength. The ratio between maxima for red and far-red fluorescence has been obtained and corrected for light re-absorption processes. Photosynthetic parameters (Fv/Fm and ΦPSII) were also calculated from the variable chlorophyll fluorescence recorded with a modulated fluorometer. Vallisneria gigantea and Azolla filiculoides were sensitive to As presence and may be proposed as bioindicators of its occurrence.