Vízrajzi Évkönyv 98., 1993 (Budapest, 1994)
Tartalomjegyzék
In some gaging cross sections, such as the reaches influenced by dams and tributaries on the Tisza River and in the Tisza Valley, the streamflow rate is influenced significantly by the surface slope as well. For such gages the relationship between the streanrflow rate, the stage and the surface slope has been detennined from the results of streamflow measurements. The daily mean discharges have been estimated using the relationship determined. For such calculations the I0 and Q0 values pertaining to the particular stage have been obtained from the tabulation containing the corresponding values of the stages (h, cm), the surface slope under steady flow conditions (I0, cm/km) and the streamflow rate (Q0, m/s) under similar conditions. Hereafter, in the knowledge of the simultaneous stage data on the auxiliary gage also indicated in the table, the actual surface slope (I, cm/km) for the given instant over the reach included by the two gages has been detennined. These data have then been entered into the foimula Q = Qo VO/Io) to find the actual streamflow rate Q(m3/s) passing the gaging cross section under consideration. For estimating the streamflow rates through the Szeged gaging cross section on the Tisza River, allowance had to be made, besides the stages on the Mindszent gage, also for the stages on the Makó gage on the Maros River. Consequently, the value of I0 had to be found from die auxiliary table in terms of die stages at Szeged and at Makó. The streamflow rates thr ough die cross sections, for which diree-, or multi-variate relationships are published can be calculated only by taking die odier two (or diree) variables simultaneously into consideration (no variable must be omitted, or neglected in die calculations). Typical water temperature data are given for die gages which are representative for longer river sections controlling die variations in water temperature. The water temperatures are measured in die morning at 10 to 40 cm depth below die water surface. The hydrological particulars (stages, streamflow rates etc.) over some streams, or sections of streams, such as die Sió Canal, some sections in die Tisza River System, are influenced by human activites, such as die operation of weirs, diversions, discharges. The extend of diese influences varies widi time, and die lengdi of the river section affected depends on stage. The duration in time and range of these effects can be indentilled by a detailed analysis of the observation data alone. The data on sediment transport - bodi for die current year and die longer period - are values estimated from observation data. The values corresponding to the highest discharges on record and observed during die year of report and before the year of report have been entered as extreme values. The concentration of suspended sediment is estimated on die basis of samples taken from 7 to 9 verticals in a cross section. Sample of one litre volume are taken at ten points evenly spaced over each vertical. The mean concentration in die vertical is found from die ten samples combined. The extreme values have been calculated by extrapolating die correlations between die quantities describing sediment transport, and should therefore be regarded as approximate values only. 4. The chapter containing die data on subsurface waters has been completed widi the water levels in die key deep wells (on artesian- and karstic waters), and widi die hydrographs of some artesian-water observation wells. The elevations of die springs above die Bälde level have in some instances been obtained from maps, in odiers by geodedcal surveying. THE MAPS OF THE DATA COLLECTION NETWORK indicate die meteorological stations gages, springs, and wells of die standard network and die stadons of die Central Meteorological Insdtute.- 19 -
