The main features of the hydrological regime of the river are strategic regional characteristics. At the same time, a significant effect on surface and groundwater runoff, evaporation and transpiration determines the landscape of the transformation of atmospheric precipitation entering the drainage area, surface and groundwater runoff. The existing basin landscape structure has hydrological properties that change when structural components are disturbed. The article examines the relationship between the intra-annual regime of the river and changes in the landscape structure of the catchment area over ten years. An estimate of the size of landscape transformations is proposed based on data on global changes in forest cover in the world in the 21st century – high-resolution global maps of changes in forest cover in the 21st century. The analysis of the dynamics of characteristics of runoff, precipitation and area landscapes is carried out. The dependence of the hydrological regime of the river on the structural transformations of the drainage landscape was revealed for the phase of the upper rainfall runoff. An increase in water discharge in the river against the background of total precipitation was noted, which indicates a change in the landscape-hydrological properties of the catchment. As a result of the reduction in the areas of dark coniferous landscapes, which have significant runoff- regulating functions of the territory of the hydrological regime, the values and amplitudes of the rises of rain floods increase. Investigations of landscape-hydrological transformations of watersheds is an important direction in optimizing the use of natural resources in watersheds and minimizing the negative impact of natural waters.

Gagarinova Olga Vladimirovna, Candidate of Sciences (Geography), Head, Hydrology and Climatology Department, V. B. Sochava Institute of Geography SB RAS, 1, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation, e-mail: whydro@irigs.irk.ru

Razdobarin Dmitry Evgenievich, Engineer of 1st Category, V. B. Sochava Institute of Geography SB RAS, 1, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation, e-mail: dmi3984@yandex.ru

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