Untersuchungen zum Einfluss von Teichwirtschaften auf die Qualitaet der Fliessgewaesser.
1988
Manz D. | Tschirschnitz M. | Teichmann W.
249 samples from the inflow and outflow of 92 different lagoons of fish hatcheries in Hesse were investigated and the results compared. The following parameters typical to fish rearing such as temperature, pH-value, oxygen content, oxygen saturation, BOD5 and ammonia were evaluated. Water quality did not decrease in all cases, at some of the sites water quality remained unchanged , in other cases there even was an improvement of water quality. The greatest decrease of water quality was observed in cases where the inflow showed a high quality (spring water). On the basis of the jurisdiction of today, 3 to 4 % of the fish hatcheries must pay duties or treat their effluent according to the regulations of the authorities. Inspite of this, all proprietors of intensive fish rearing are recommended to treat or at least aerate their lagoon effluents.
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