Structural and hydrographic analysis of river systems in the basin of Baikal lake

A structural and hydrographic analysis of the river systems of the Lake Baikal basin has been carried out. The information basis of the study is the data of average annual water discharge in the sections of the standard observation network. A static model of river systems (RS) is constructed using medium-scale topographic maps for the study area. The use of modem GIS-technologies allows to build a dynamic model and to carry out analysis of river systems at the level of the water-erosion network. A static model is an aggregate a constantly functioning river network. This model is constructed for the average long-term mnoff of the low-water phase of the water regime. The dynamic model corresponds to the phase of extreme runoff at maximum moistening. In the dynamic model, there is an increase in the number of elementary watercourses due to the activity of all drainage gullies, caused to the relief of each particular basin. The order of the river systems according to the Horton- Strahler classification was determined and the bifurcation coefficient was calculated for the static and dynamic model. The feasibility of applying the bifurcation coefficient is determined for the dynamic model. The number of mouths of watercourses, which flowing into Lake Baikal is estimated of the dynamic model. A comparative analysis of the order rivers of the static and dynamic models was performed, as a result of which the importance of different-scale topographic maps and a digital terrain model for investigating the river or channel network within the framework of structural hydrography was identified.