MODELLING THE EFFECT OF SEWAGE LOADING AND OCCURRENCE OF MACROPHYTES ON THE OXYGEN CONCENTRATION IN SOME DANISH WATERCOURSES
The stream fauna is among other things dependent on the oxygen content of the water. So in recipient quality planning it is essential for the authorities to be able to investigate the effect of different loading situations on the water. The paper describes an investigation in the Langvad å drainage system in Zealand, Denmark, where a deterministic oxygen balance model was used to describe the diurnal oxygen variations and to estimate some process parameters in several watercourses. Based on the results and by means of multiple regression analysis two empirical equations were obtained for reaeration and respiration in streams. These equations can be used in connection with the model to simulate the oxygen conditions if the BOD loading, amount of macrophytes and water discharge are known. “Complete abstract not presented.”