Study on the water quality of the Pisia–Gągolina river, one of the most interesting environmental object, was carried out. Samples of water for chemical research was taken twice a year: winter and in spring. Physical and chemical parameters of water quality were determined in comparison with legal requirement for five quality class of surface water. The most impact on water pollution has concentration of phosphate, dissolved oxygen and amonium. The concentration of dissolved oxygen depended on season and place of sampling. Present level of reservuares water contamination indicates eutrophication of river. ...
The results of research over influence of air temperature on oxygen condition in carp pond are present in this paper. Mean of dissolved oxygen concentration observed at 8 am were equal 7,18 mg O2·dm-3, at 2 pm – 12,76 mg O2·dm-3 and at 8 pm – 13,37 mg O2·dm-3. Large fluctuations of dissolved oxygen concentration in the euphotic zone of eutrophic fish pond were observed. Oxygen condition lower then lower limit of dissolved oxygen concentration for carp (5 mg O2·dm-3) were observed at 8 am (minimum = 2,34 mg O2·dm-3). The highest oxygen concentration were observed in the afternoon (14 pm) and in the evening (8 pm). The highest oxygen concentration were equal 25,8 mg O2·dm-3. Analysis of connection between air temperature and dissolved oxygen concentration revealed weak but essential relationship for the results from 2 and 8 pm. Increase of oxygen concentration was observed with increase of air temperature. ...
The results of research on influence of insolation on oxygen condition in carp pond are present in this paper. Mean of dissolved oxygen concentration observed at 8 am were equal 7,18 mg O2•dm-3, at 2 pm - 12,23 mg O2•dm-3 and at 8 pm - 12,79 mg O2•dm-3. Large fluctuations of dissolved oxygen concentration in the euphotic zone of eutrophic fish pond were observed. Oxygen condition lower then lower limit of dissolved oxygen concentration for carp (5 mg O2•dm-3) were observed at 8 am (minimum = 2,40 mg O2•dm-3). The highest oxygen concentration were observed in the afternoon (14 pm) and in the evening (8 pm). Analysis of connection between insolation and dissolved oxygen concentration revealed weak but essential relationship for the results at 8 am, 2 pm and 8 pm. Increase of oxygen concentration was observed with increasing of insolation.
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The article presents common used methods for measuring dissolved oxygen concentration at wastewater facilities. The described methods include Winkler titration and instrumental measurements, such as electrochemical sensors and more recent developed optical ones. The principles, analysis procedures as well as advantages and drawbacks of the methods were discussed. Furthermore, the valid ISO and PN-EN standards for dissolved oxygen measurements were shortly presented with emphasis on the recent changes concerning standards for the optical sensor method. As the results of a survey conducted among wastewater treatment plant operators in southern Poland reveal, optical sensors are being currently preferred in on-line applications due to their enhanced properties in comparison to other measurements methods. ...
