The dependence of sheet erosion velocity on slope angle
The article presents a method for estimating the erosion velocity on forested natural area. As a research object for testing the methodology the authors selected Neskuchny Garden - a city Park on the Moskva river embankment, named after the cognominal Palace of Catherine's age. Here, an almost horizontal surface III of the Moskva river terrace above the flood-plain is especially remarkable, accentuated by the steep sides of the ravine parallel to St. Andrew's, but short and nameless. The crests of the ravine sides are sharp, which is the evidence of its recent formation, but the old trees on the slopes indicate that it has not been growing for at least 100 years. Earlier Russian researchers defined vertical velocity of sheet erosion for different regions and slopes with different parent (in relation to the soil) rocks. The comparison of the velocities shows that climatic conditions, in the first approximation, do not have a decisive influence on the erosion velocity of silt loam soils. The velocities on the shores of Issyk-Kul lake and in Moscow proved to be the same. But the composition of the parent rocks strongly affects the sheet erosion velocity. Even low-strength rock material reduces the velocity by times. Phytoindication method gives a real, physically explainable sheet erosion velocities. The speed is rather small but it should be considered when designing long-term structures on the slopes composed of dispersive soils. On the slopes composed of rocky soils sheet erosion velocity is so insignificant that it shouldn't be taken into account when designing. However, there may be other geological processes, significantly disturbing the stability of slopes connected with cracks.