Особенности проявления эрозии в пределах овражно-балочного водосбора

Abstract

Purpose: to determine patterns of formation of hydrographic network elements depending on the melt-and rainwater runoff and soil losses. Materials and methods. The studies were carried out in the upper reaches of the Bolshoy Log gully system, which is a part of the land use of the experimental farm “Polevoy” of the Federal Rostov Agrarian Research Center, with an area of 2070 hectares, of which more than 70 % is arable land. Soils are ordinary chernozems of varying degrees of erosion. The standard methods of research and the method of pins were used on runoff plots. Results. Within the catchment area, the amount of runoff and hydraulic indicators of water courses are greatly influenced by the agricultural background and the soil surface condition from which meltwater flows, and the intensity of erosion processes is influenced by the depth of soil freezing, the moisture content of topsoil, water storage in snow, snowmelt intensity. The water sprays are concentrated along the gullies, where the soil is washed out over time, and they pass into the category of hollows, then into ravines and gullies, forming a hydrographic network in the gully-ravine catchment area. The most intensive meltwater runoff was observed over the years: in 1988 – 33.8 mm, 2003 – 63.9 mm, 2006 – 24.6 mm, 2014 – 14.3 mm, 2017 – 19.3 mm, 2023 – 10–14 mm. In the variants with reclamation protective forest plantations and hydraulic structures, the runoff was 5–12 mm less than in the control and it retained in the forest belt. The mathematical data analysis made it possible to determine the relationship between the runoff rate and soil loss in the gully-ravine catchment, depending on the distance from the watershed. Conclusions. On the gully-ravine catchment, the sheet wash smoothly turns into a linear one and forms hollows and valleys. The final link of the catchment area are ravines and gullies. During the peak periods of meltwaters, the water flow velocity on flat sections of the slope is 0.33–0.46 m/s, and along the hollows – 0.57–0.83 m/s.