Результаты экспериментальных измерений эрозионных потерь почвы в свально-развальных бороздах и в ручьях, сформировавшихся на сельскохозяйственном поле с выпаханными почвами (бассейн Сухой Орлицы Орловского района Орловской области)

Abstract

Erosion losses of soil in agricultural fields are difficult to account for due to the need for a differentiated approach to assessing soil losses due to the complex structure of the field surface, and, consequently, due to the need to model the process in each of the areas that differ in the conditions of erosion processes. The article discusses the technology of accounting for erosion losses of soil in dump-collapse furrows and in streams formed by rainfall, in areas of agricultural fields, the soils of which differ in the degree of ploughing. The results of an experiment conducted on a site with gray forest soils ploughed to varying degrees are presented. The plot is located in the Oryol district of the Oryol region. The soil-morphological method using the cesium-137 isotope of Chernobyl origin as a marker was used to determine the volume of washed-off soil delivered to the receiving ravine (3-4 tons/ha per year) from a 50,000 m2 hollow, the territory of which is occupied by weakly plowed and very weakly plowed soils. Layer-by-layer sampling of soil by depth in the thalweg of a stream formed in two plots (with strongly plowed and weakly plowed soils) made it possible to determine the degree of soil erosion in the thalweg of this stream in each of the plots. It was found that both in strongly plowed and weakly plowed plots the intensity of soil loss in the stream formed by rainfall is equally high. Heavily plowed soils lose soil in a stream in a volume 2.3 times greater than the amount of soil washed away in the dump-collapse furrows on the same site and 5.4 times greater than the amount of soil washed away in the dump-collapse furrows on a site with very weakly plowed soils (on the watershed space). It is proposed to take into account the erosive soil losses in streams in the calculation scheme by introducing an increasing coefficient to the data obtained from the soil loss intensity map published earlier. The locations for introducing the coefficient can be determined by overlaying (in a GIS environment) the map on a high-resolution satellite image with dump-collapse furrows. The coordinates of the thalwegs of streams should be determined using GPS or data obtained from unmanned aerial vehicles (UAVs). Keywords: SPACE IMAGE, CESIUM-137, HOLLOW COMPLEX, PLOWED SOILS, DUMP-RUIN FURROWS, STREAMS, RAINFALL, SOIL WASH-OFF