Hydrological–Morphological Zoning of the Mouth Zone of the Selenga River

According to the two-term principle of zoning of mouth areas, parts of the mouth area of the Selenga River are recognized and their boundaries are determined based on hydrological–morphological characteristics.     

Hydrological and morphological features of the Upper Angara mouth area

The hydrological and morphological processes in the mouth area of the Upper Angara (which ranks second in terms of water abundance among Baikal Lake tributaries) are considered. The major external factors that determine those processes have been revealed. The main features of the delta??s water regime, including the effect of anthropogenic level rise in the lake, are described. Specific attention is paid to morphological processes in the delta and on the barrier bar, separating a large mouth lagoon from the lake.     

The geometric pattern of Lake Baikal's shores

A general characterization of the geometric patterns of Baikal's shoreline is provided. We consider in detail smooth and bay shores of several types, including the ria and fault-line coasts. We demonstrate the significance of young faults and palaeoseismodislocations of the various types of shore area.     

Climatic factors as risks of recent ecological changes in the shallow zone of Lake Baikal

Eutrophication processes have been recorded in many world’s freshwater reservoirs, which are sources of drinking water. More and more investigations show that global warming is the main natural factor that causes eutrophication. In recent years, signs of eutrophication have also been recorded in Lake Baikal containing 20% of the world’s freshwater reserves. Therefore, we performed the first comprehensive analysis of long-term changes in climatic parameters capable to provoke negative changes in the shallow zone. The largest number of anomalies of climatic indices has been recorded in the 21st century. Moreover, the current decade has been the most favorable for the emergence of negative processes in the lake (outbreak of the mass growth of algae and aquatic vegetation, rotting of their remains at the bottom and on the shores of the lake, changes in the structure and zoning of biocoenoses, etc.). The main natural conditions favoring the emergence of negative signs are elevated temperatures of the air and lake shore water, reduced amount of precipitation, reduced inflow of river waters into Baikal and lowering of its water level, low-water season, and weakening of wind currents, water exchange processes, and, as a result, water self-purification. In the period of continuing global warming, it is necessary to study the climate effect on the processes in the shallow zone and to carry out long-term monitoring for elucidation of recent and expected changes in the ecological state of Lake Baikal and for their valid interpretation.     

Sediment runoff formation trends of major tributaries of Lake Baikal in the 20th century and at the beginning of the 21st century

Presented are the results of the analysis of sediment runoff variations of main tributaries of Lake Baikal in the 20th century and at the beginning of the 21st century. It is revealed that the sediment runoff decrease has been observed in the tributaries since the second half of the 1970s. Considered are the reasons for such trend being peculiar in different areas of the lake basin.