Preliminary communication
THE CHANGE OF WATER CHEMISM IN CARP POUNDS
1996, 54 (2) p. 65-74
Krešimir Fašaić, Ljubica Debeljak, Radovan Erben, Mirko Turk
Abstract
The researches has been conducted in the test ponds of fishfarming „Draganići“ each of them O.25 ackres great and 1 meter deep. During the breeding season of 1991, there have been examined the effect of mineral fertilizers NPK (12: 12: 12) and the reinforced nutrition of the fish with the protein briquettes (»Gloria«) on the chemism in the test ponds. During the breeding season, there have been stated certain differences in the quantity of the 02, NH4+, NO-, P043- and the outgoings of KMn04 among the separate variants of the treated ponds and the inflow water of the brook Stojnica (Tables 1, 2-6) and also the significant oscillations of all chemical indicators. The average quantity of 02 in the separate pond variants has reduced between 5% and 13% in relation to inflow water and the quantity of N03- between 24% and 43%. The outgoings of KMn04 has increased between 6% and 22% as compared with the inflow water. The reduction of 02 and N03- and the incensement of outgoings of KMn04 in the test ponds has not been significant (P 05). The quantity of NH4+ and P043- has increased between 36% and 82% and between 49% and 113% in all variants of test ponds respectively as compared with the inflow water. The differences are significant (PO. 05). The asserted differences about the quality of separate chemical parameters in the variants II. and III. as compared with the control variant I. has been significant (PO. 05) only for the quantity of NH4+ and P043-.