E-catalog        

Библиогр.: 32 назв.

A study is made of the role of bogs in the formation of the annual runoff within the Middle Ob basin and its intra-annual distribution as well as making an assessment of the swampiness of the river catchments by using Landsat space images. It is shown that the overall swampiness of the catchments of almost all rivers under investigation(except for the Shegarka, Kargat, Chichka-Yul and Bol’shaya Yuksa rivers) as determined by analyzing the space images of the study territory exceeds, on the average, he previously obtained data by a factor of 1.5–2, while the influence of the bogs on the streamflow is different and depends on the occurrence of separate groups of bog microlandscapes, the structure of bog massifs, the character of location of the bogs on the catchment, and on the course and stage of their development. The area along the left bank of the Ob is dominated by raised bogs (49%) of the central-oligotrophic course of development and shows a regular alternation of definite groups of bog microlandscapes from the middle part to the margins of the bogs, and an almost total merging of elementary bog massifs to form major bog systems, such as the Vasyugan Swamp. As a result, the influence of the bogs on the streamflow is more clearly pronounced there. Along the right bank of the Ob, in conditions of the larger dissection of the terrain, the peripheral-oligotrophic course of development of the bog massifs is dominant, almost all bogs are in early stages of their development, with transition bogs predominating (49%) so that the bogs have a smaller influence on the streamflow. In conditions of an increase in swampiness of the catchments along the right bank of the Ob, it is found that the mean long-term layers of flow increase, whereas along the left bank the inverse situation is observed. The area along the right bank of the Ob shows an increase in evenness of the discharge within a year is observed with an increase in swampiness of the river catchments. The intra-annual runoff distribution of the rivers in the area along the left bank of the Ob is characterized by a larger irregularity, and by a decrease in the runoff at the low-water period with an increase in the area of the bogs.