Scientific Congress Presentation
THE CHANGE OF CHEMICAL QUALITY OF CARP POUNDS OUTGOING WATER IN RELATION TO INFLOW WATER
1996, 54 (4) p. 181-192
Abstract
Carp pounds are considered one of the contaminators of open waters. Such situation was the motive for carrying out the research of changes in the outgoing water from a pond compared to the water flowing into ponds on the fish-farming »Jelas« near Slavonski Brod. The research was carried out in the period 1989-1995, in spring, summer and autumn on the fish production of 500-1000 kg/ha-1 and fish nutrition with cereals. Following chemical parameters were researched: 02, unbound C02, alkalinity (CaC03, CaHC03), pH, permanganat number (KMn04). BPK5, total dry waste, suspended substance, NH4+, N03- and PO43-. On the basis of received analytic values, it was concluded that the water may be categorized in I-II quality class according to the quantity if 02, consumption of KMn04, NH4+, N03-, PO43- and dry waste in the feeding and drainage canal and in the III-IV quality class according to the BPK5 and suspended substance. An occasional marked decrease of the quantity of 02, NH4+, N03- and PO43- and alkalinity of water was stated in the outgoding water compared to the inflow water. The BPK5 and suspended substance increased in the outgoing water compared to the inflow water. After the variant of the most important inflow and outgoing chemical parameters in the water was analyzed, it was stated that there emerged no significant changes (P>O.Ol, P>0.05). The changes of outgoing water from fish-farming “Jelas” were not significant in the research period and they had no significant influence on the change of the recipient water.