ВЛИЯНИЕ ЛЕСА НА СНЕГОНАКОПЛЕНИЕ (ПО ДАННЫМ ПОДМОСКОВНОЙ СТОКОВОЙ СТАНЦИИ

Engineering culverts and drainage structures are designed when solving land reclamation problems and road construction. Since the main parameter in calculating the dimensions of bridge or pipe holes or sections of drainage ditches is the extreme flow rate, its correct determination has a great influence on design decisions. Extreme flow rates on most rivers occur during the spring flood, so to correctly determine this flow rate, it is important to understand the conditions of flood formation.

In the mixed forest zone of the European part of Russia, with drainage areas of more than 100 km², the flood of the spring flood almost always exceeds the storm flood in magnitude. Its volume is determined by the water reserves in the snow cover at the beginning of snow melting, and its consumption is determined by the amicability of the spring flood. Therefore, the study of the conditions for the formation of snow cover, its distribution over the river basin is of great scientific and practical interest. The accumulation of snow reserves strongly depends on the degree of coverage of the catchment area with forest, especially in the zones of taiga, mixed forests and forest-steppe. The main runoff-forming characteristic of the snow cover is the maximum snow storage - the total amount of water in solid and liquid form contained in the snow cover at the time of its maximum accumulation. For example, for the forest and field catchments of the Moscow Region runoff station, the maximum snow reserves in individual years differ in moisture content up to 60%. The redistribution of snow reserves in favor of the forest leads to later snow melting and, as a consequence, spreading of the peak of the spring flood. The maximum moisture reserves in snow in the forest exceed those in the open area according to long-term data by an average of 10%, however, the coefficient taking into account the influence of the forest on the runoff takes values of 30–40%, which is confirmed by observation data. The article notes the difference between the flood friendship coefficients calculated according to its physical meaning and determined from the data of analogous rivers in the opposite way