Vízrajzi Évkönyv 86., 1981 (Budapest, 1982)
Tartalomjegyzék
The concentration of suspended sediment is estimated on the basis of samples taken from 7 to 9 verticals in a cross section. Samples of one litre volume are taken at ten points evenly speced over each vertical.The mean concentration in the vertical is found from the ten samples combined. The extreme values have been calculated by extrapolating the correlations between the quantities describing sediment transport, and should therefore be regarded as approximate values only. No fords were reported during 1981 on the Tisza River, so that data on fords are presented for the Danube alone. 3. The chapter containing the data on subsurface waters has been completed with the water levels in the key deep wells /on artesian- and karstic waters/, and with the hydrographs of two artesian-water observation wells. The elevations of the springs above the Adriatic level have in some instances been obtained from maps, in others by geodetical surveying. 4. In the chapter on hydrometeorological data,in the tabulation of monthly and annual precipitation depths, the stations reporting daily have been indicated by underlining. The water equivalents of the snow cover have been calculated from the results of 20 samples taken along a straight line /2 samples taken at 10 points along a distance of round lOO m/. Evaporation from the open water surface has been estimated from the data of pans comprised in the network operated by the district water authorities. Evaporation from natural water bodies may be from 0.7 to 1.1 times of pan evaporation, depending on local particulars /area of the water surface, depth of, and vegetation in, the water body, wind exposure etc./. THE MAPS OF THE DATA COLLECTION NETWORK indicate the gages, springs, wells and meteorological stations, which were operated over the year of report, or over a part thereof. The stations abandoned during the year have been noted in the column of remarks. — 25 —
