Diurnal variation of Texas 'brown tide' (Aureoumbra lagunensis) in relation to metals

The diurnal variability of Aureoumbra lagunensis, dissolved metals (Cd, Pb, Mn, Cr, Cu, Zn, Ni, Se, and Fe), and environmental parameters (salinity, temperature, turbidity, pH, and dissolved oxygen) were studied to understand the role of metals in the occurrence of the Texas 'brown tide'. The A. lagunensis densities were high in the afternoon; suggesting the influence of light on the growth of A. lagunensis. The results indicate that metals, Cd, Pb, Mn, Cr, and Se may not be influencing the growth of A. lagunensis. The dissolved Cu, Zn, and Ni concentrations were inversely related with A. lagunensis densities while Fe had positive relationship with A. lagunensis. The spectroscopic characterization of the surfaces of A. lagunensis suggests that these metals might be playing a role in the occurrence of Texas 'brown tide' through involvement of -OH and -CH functional groups on the surfaces of A. lagunensis.