The paper deals with the essence and main directions of the complex analysis of the river systems state in mountain and highland regions of Ukraine. Their functioning (as water, sediments and dissolved substance runoff riverbed morphology changes under influences of the riverbed and slope processes) and long-term changes in the morphology and geoecological state of the rivers and their catchments due to natural and man-made factors are characterized. The investigations were based on comparative morphometric analysis of the river systems structure, field and stationary observations of the nature components state within the catchments, determination of the anthropogenic pressure on the landscapes. As the result the tendencies, scales and intensity of transformation and degradation processes development in different parts (subbasins) of the river basin systems in the Polissia, Volyno-Podillia, Precarpathians, and Ukrainian Carpathians have been ascertained. The measures for improvement of the river basin systems state and optimization of nature use have been proposed.
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