Oxygen, dissolved colonies

Figure 2A and B. Contours of dissolved oxygen in colonies of P. ovalis of different sizes. Note that the colonies are much smaller than those shown in Figures 2C and 2D. Continued on next page. 

In acute toxicity tests, the white amur (grass carp) was not affected at three times the recommended rate of 1 x 10° colony forming units per milliliter. Rates of ten times the recommended rate caused significant mortality (90 %) to fish (Joye, unpublished data). However, mortality may be due to excessive turbidity and reduced levels of dissolved oxygen rather than to any toxic effects. Further work is planned to determine the cause of the observed mortality. 

Dissolved Oxygen Contours in Pseudomonas ovalis Colonies... 

Figure 1, Dissolved oxygen profiles from typical traverses of a microelectrode through a P. ovalis colony. Colony diameter, 1.5 mm 40 mg/L glucose. Key A, center line of colony B, 0.5 mm from center C, 0.75 mm from center D, 1.0 mm from center.

Figure 2C. Contours of dissolved oxygen in a colony of P. ovalis. Continued on next page.

BOD = biological oxygen demand DOC = dissolved organic carbon COD = chemical oxygen demand CO2 = carbon dioxide production CPU = resultant number of colony-forming units DW = dry weight SAM = specific analytical method. 

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