Link between hydric potential and predictability of maximum flow for selected catchments in Western Carpathians

This study aimed to determine the link between a hydric potential of catchments (LHP) and the predictability (P) of maximum flow of selected rivers in southern Poland (within the Upper Vistula basin) and Slovakia. The LHP method refers to the ability of ecosystems to slow down runoff and retain water. The LHP method is focused on the analysis of the following indicators, shaping the geosphere at the catchment scale: hydrogeological conditions, soil conditions, meteorological conditions, geomorphological conditions, and land use. The predictability of river flows, calculated as one of the Colwell's indices, represents a measure of confidence with regard to the state of a flood event at a given point. To determine links between the LHP and P, a cluster analysis was used with the Ward method of agglomeration. The mean LHP varied between 1.2 for the Skawa River and 20.1 for the Vistula River. Only the Vistula River has very high LHP. The rest of the investigated rivers had medium and low values of LHP. The mean predictability of maximum flows for all rivers was relatively high (0.54), with the highest value obtained for the Wisłok River (0.69) and the lowest one for the Białka River (0.40). Cluster analysis showed that the studied catchments may be aggregated into four homogeneity clusters: first - catchments with high P and limited LHP, second - catchments with mean P and low LHP, third - with low P and average LHP and fourth - with very high P and medium and excellent LHP. The results are important for the management of catchments, especially for planning of any land use changes and investment projects related to water retention.