Final Report - ICPDR

4 Results and discussion
4.1 Chemical status characterization
4.1.1 On board analysis of water
Results measured on-board concerning the water samples are summarized in Table
4.1.1.1 (Yellow color indicates the tributary samples). The water temperature was in
the range of 15-16,7 o C, the pH values indicate slightly alkaline medium. The
dissolved oxygen is not far from 100 % saturation along the whole Tisza, icluding the
tributaries, except the Bega (2,9 mg/l DO– 32 %).
The electric conductivity of the Tisza is around 300 µS/cm, conductivity values of the
tributaries are a little higher (maximum value in the Sajó: 550 µS/cm). Alkalinity is
smaller in the Tisza than in its tributaries (maximum value in the Zagyva: 7,3 mval/l).
The amounts of the main inorganic nutrient compounds are indicated in Figures
4.1.1.1-4.
2,50
2,00
Concentration of NO3-N (mg/l)
1,50
1,00
Tisza
tributaries
0,50
0,00
0 100 200 300 400 500 600 700 800
Distance (km)
Figure 4.1.1.1 Amount of NO 3 -N in the Tisza and its tributaries, ITR, 2001
The amount of nitrate nitrogen is slightly decreasing in upstream direction after the
Kisköre Reservoir. Maximum values are shown in the Zagyva and the Sajó reaching
2,5 mg/l concentrations. The same tendency is shown on Table 4.1.1.2 where the
nitrite nitrogen is illustrated. Tributaries such as the Bega and the Zagyva contained
much more of this compound than the others and the Tisza itself (max. 0,066 mg/l).
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