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Variability and Trends in the Vişeu River Runoff Regime. The classic hydrological water management dealt with the changing resources by assuming the existence of stationarity. Once stationarity is neglected in the design of hydraulic engineering, numerous errors and risk may exist in the operations and management strategies and will lead to unforeseen losses. Thus, one of the most important questions in today's hydrology are: Did stationarity die? and if it is true How did stationarity die? As we know the climatic change is widely accepted so it is sad that by 2050 the effects of climate change may have a generally larger effect on flow regimes than it is estimated that dams and water withdrawals. If this is so, we must consideration that in this moment one of the most important aspect/moment is the change point identification in a period, from where significant change has occurred in a time series, for this we choose to use the Ms Excel Addinsoft XLStat to assess the homogeneity of the data by the Pettitt's test, the von Neumann ratio test, the Buishand range test and also the standard normal homogeneity tests (SNHT). For the trend analysis we used the Mann-Kendall test and the classic linear regression test. Based on the results, we conclude that in case of the Vişeu watershed stationarity is questionable if not totally missing. As we see even if the precipitation values do not show significant changes regarding their homogeneity, the runoff series are changing and in most cases this change is identified in the 20thcentury last decade. These results urge us to rethink and to reevaluate our sustainable water resource management for the future. [ABSTRACT FROM AUTHOR]

One of the possibilities to establish the tendency of evolution of a territory from a hydrographical point of view is the knowledge of the degree or rate of finishing of the drainage basins. This indicator, closely connected to the law of the number of streams, provides information about the stage of evolution of the drainage basins. In order to calculate this indicator, we selected 35 drainage basins of different orders in the Transylvanian Depression. Most of them have a value of the indicator below 1. This fact indicates a hydrographic evolution based on the increase of the number of first order segments in Horton-Strahler system, to reach values equal or higher than 1, specific for the drainage basins in a more advanced stage of evolution. The occurrence of new first order river segments within the drainage basins has effects both at the level of the already existing riverbeds, which perform the transit of alluvia, and at the level of slopes, the common place of formation for gullies and ravines. [ABSTRACT FROM AUTHOR]