ИСТИНА

Baikal is the deepest lake in the world and the unique ecosystem. The aim of this research is to assess the impact of climate and land use change on the characteristics of permafrost of different types and corresponding hydrological processes. The analysis of the long-term variability of characteristics of river inflow and permafrost conditions using the historical data was conducted as well possible changes were projected based on hydrological modelling. The basin of the Lake Baikal has area about 545 000 km2, half of which is situated in Russia. It is characterized by different types of continuous and discontinuous permafrost, various climate and landscape conditions and annual flow depth varying from 30 to more than 600 mm within the studied area.Land use changes (fires, for example) and climate variations have a strong impact on the permafrost conditions and the regime of rivers inflow to the Lake. The watersheds response caused by environmental non-stationarity can be variable and unpredictable.Therefore adequate hydrological models with accounting for permafrost and robust parametrization are required for future projections. Several small and middle-size representative watersheds in different parts of the Lake basin with area from 151 to 7800 km2 with various permafrost conditions and different types of hydrological regime were chosen for the study.The data base for modelling was developed which included the information about landscapes, soils, permafrost characteristics and dominant hydrological processes. The hydrological model parameters for different types of permafrost conditions and dominant landscapes were estimated based on that information. We applied distributed process-based hydrological model Hydrograph [Vinogradov et al., 2011, Semenova et al., 2013]. It describes all essential processes of land hydrological cycle including detailed algorithm of water and heat dynamics in soil accounting for water phase change [Semenova et al., 2014].The Hydrograph model was validated for the historical period and then used in projection mode with the conceptual scenarios of climate and land use change. The results of modelling projections were explored and the conclusions about possible changes of river inflow to the Lake Baikal were drawn. We propose that the Hydrograph model can be applied as the tool to estimate riverine inputs into the lake’s systems in permafrost environment. The example of such approach is demonstrated here. Acknowledgements The study was partially supported by Russian Foundation for Basic Research (project 15-35-21146 mol_a). References Semenova, O.; Lebedeva, L. and Vinogradov, Y.[2013]: Simulation of subsurface heat and water dynamics, and runoff generation in mountainous permafrost conditions, in the Upper Kolyma River basin, Russia. Hydrogeology Journal, 21(1):107–119,doi:10.1007/s10040-012-0936-1. Semenova, O.; Vinogradov, Y.; Vinogradova, T. and Lebedeva, L. [2014]: Simulation of Soil Profile Heat Dynamics and their Integration into Hydrologic Modelling in a Permafrost Zone. Permafrost and Periglacial Processes, 25(4):257–269,doi:10.1002/ppp.1820. Vinogradov, Yu. B.; Semenova, O. M. and Vinogradova, T. A. [2011]: An approach to the scaling problem in hydrological modelling: the deterministic modelling hydrological system. Hydrological Processes, 25(7):1055–1073, doi:10.1002/hyp.7901.