CHANGES OF THE MINIMUM MULTIANNUAL DISCHARGE ON THE CRASNA / KRASZNA STREAM

Changes of the minimum multiannual discharge on the Crasna / Kraszna Stream. 72% of the Crasna/Kraszna River catchment area of 3142 km2 is situated on Romanian area, while 28% of it is situated on Hungarian area. In the last decades, a significant change occurred in the characteristics of the many years’ water level fluctuation on the lower river section on Hungarian area, as the investigations carried out in the previous years have already indicated based on the annual characteristical discharge data. The change can be determined also considering the medium and maximum discharges, but especially it is significant in the low water periods. On account of revealing the reasons and main characteristics of the changes, we have carried out the detailed statistical study of the last six decades’ daily discharge data, their many years’ development, on the other hand we have carried out the comparing study of the low water characteristics of the stations situated on the middle and lower river section. The increasing trend of the daily minimal discharge values and the decreasing trend of the number of low water days is in opposite direction with the decreasing trend of the precipitation change.