THE CONDITIONAL FACTORS AND THEIR INFLUENCE UPON THE EVOLUTION OF FLASH FLOOD PHENOMENA IN THE UPPER RIVER BASIN OF MURES

Headnote

Abstract:The floods conditional factors in the upper river basin of the Mures are mainly the ones of a geomorphological nature combined with the vegetation coverage and human impact upon the environment were this impact of positive or negative nature.

The floods in the upper basin of the Mures are not phenomena of great amplitude and as such the damage they inflict is rather moderate, except in abnormal cases. Most localities that have reported damage caused by floods are located near the Toplita-Deda gorge, an area that influences flow concentration through a relatively narrow territory compared to the upstream territory where the Mures river gathers its tributaries.

Keywords:conditionalfactors, flash floods, upper river basin of Mures

1. GENERAL CONSIDERATIONS

The study begins by analyzing the general characteristics of the upper side of the Mures river basin, followed by an emphasis on the geomorphological elements, the vegetation coverage and the human factors as main conditional factors of the flash floods occurring in the upper river basin of Mures.

Given the location of the basin in a mountain area a major influence on the formation and evolution of floods is represented by the cooperation of the climatic and geomorphological factors and thus the area can be divided into two parts: the gorge area where under the effect of the geomorphological factors the system responds by influencing both its hidrological and its climatic components fact manifested through the concentration of water in the path of air masses and the second part which is a lowland area where the air masses are now depleted of precipitation and there is no concentration effect induced by the geomorphological elements.

2. THE GEOMORPHOLOGICAL ELEMENTS AS CONDITIONAL FACTORS TO THE EVOLUTION OF FLASH FLOODS WITHIN THE UPPER RIVER BASIN OF MURES

The geomorphological elements have an indirect influence upon the flash-flood evolution as they bear on the climatic factors that generate the flash-flood itself through morphometric elements specific to the mountain area: steep slopes that generate a rapid development of streams, high altitude, relatively elongated shape of the studied river basin and the subasins.

The shape of the Mures river basin is rather an oblong one fact that reverberates in the magnitude and timing of the peak flow (3,4).

Considering the tributaries basins shape...