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The effect of amino and polycarboxylic acids on the toxicity of cobalt to phytoplankton cells

100%

Kosakowska A.

Oceanological Studies

1996

vol. 25

issue 4

47-54

The effect of the amino acids l-cysteine (CYS-SH), l-aspartic acid (ASP-OH) and l-glutamic acid (GLU-OH), and of polycarboxylic acids (PCAs) on the biological activity of co-balt in cultures of Scenedesmus armatus (Chodat) and Synechocystis aquatilis (Sauvageau) was investigated. The influence of metal ions was determined by measurements of chlorophyll a content in the cultures and rates of carbon fixation by the phytoplankton cells. The addition of cobalt (2.5*10-6 M) to the cultures caused inhibition of growth, monitored by the chlorophyll a concentration and the photosynthetic rate of both green algae and cyano-bacteria. It was found that these acids significantly increased the chlorophyll a content in both algal species when treated with cobalt. Polycarboxylates, CYS-SH and ASP-OH also increased the rate of C-14 incorporation into algal cells in both cultures, whereas GLU-OH was effective in cultures of Synechocystis only.The results indicate that organic compounds, polycarboxylates and amino acids modify the biological activity of the cobalt. The environmental consequences of these processes are considered.

The geochemical profile of bottom sediments in the Domiaza (Oder river estuary, northwest Poland)

67%

Piotrowski S., Laba-Mydlowska E.

Oceanological and Hydrobiological Studies

2003

issue 4

79-115

The Domiaza is a fragment of the Oder river estuary situated north of Szczecin. This area is exposed to complex hydrological processes and strong anthropogenic pressure. Key physical and chemical parameters of the Domiaza sediments (fraction < 2mm), e.g., dry residue (Ds), ignition loss (Iz), CaCO3 and organic carbon content, show high coefficients of variation (over 60%). Similar variation is typical of the heavy metal concentrations (Cu, Zn, Pb, Co, Cd and Hg) and the organic carbon content in the fraction smaller than 0.20 mm. The spatial distribution of the examined parameters in the Domiaza sediments results from the dynamics of this environment, especially the heavy watercraft traffic and the continuous dredging of the Szczecin-Swinoujscie water lane. Concentrations of Cd, Cu, Zn, Pb and Co found in the Domiaza sediments are higher than those found in the geochemical background of Poland, while concentrations of mercury are comparable. Moreover, the concentrations of Cu, Zn, Pb and Cd found in the Domiaza sediments are higher than the average concentrations of these metals in adjacent areas (Oder River, Dabie Lake, Szczecin Lagoon), but the concentrations of Hg and Co are comparable or lower depending on the area of reference. A survey of heavy metals concentrations conducted in 1999 detected higher than average concentrations of Cu, Zn, Pb, and particularly Co (twice) and Hg (over thirty times), and lower concentrations of Cd in comparison with the average levels of 1996. The reason for these differences was the selective inflow of heavy metals to the Domiaza area after the disastrous flood of 1997.

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The effect of amino and polycarboxylic acids on the toxicity of cobalt to phytoplankton cells

The geochemical profile of bottom sediments in the Domiaza (Oder river estuary, northwest Poland)