Author(s): Gusev Mikhail Nikolaevich; Pomiguev Yuriy Vasilevich
Linked Author(s):
Keywords: River valley bottom; Channel; Channel deformation; Alluvium; Human activities
Abstract: The Amur River is the largest water-flow in the North-East of Asia. It drains the territories of the three countries – Mongolia, China and Russia. The total area of its Basin is more than 1. 8 million km2. At the extent of almost 2 thousand km the Amur River is a borderline between Russia and China. But the morphodynamics of its valley bottom (including its channel) is not sufficiently studied. This hampers the efficient use of its resources. This paper is dedicated to the study of the features of the Amur River valley bottom formation in the natural environment in the Holocene and to its transformation under the conditions of the modern nature management at its mid-stream section (from the Zeya River mouth to Khingan Gorge) extending for 400 km. This work is based on the combined analysis of geostructural, tectonic, lithological and geomorphological conditions of its channel formation, morphometric parameters of the channel as well as on the results of the studies of modern alluvium (its properties, composition, thickness and its distribution patterns along and across the valley bottom) and also on the data on the recent tectonic movements in the Amur region. The Amur River is experiencing the resulting (directed) right-shift in the forming of the valley bottom. At the same time the dynamic state of the river valley bottom is characterized as similar to the equilibrium state due to a slow incision of its water flow into the underlying rocks with the velocities of 0. 9 - 1. 1 mm per year. The modern character of the economic activities transform the fluvial regime formed during the Holocene and this resulted in significant changes in the river channel and banks dynamics as well as in its floodplain development. The Zeya and Bureya hydroelectric power stations and the facilities of the right bank infrastructure impact most of all on the river activity. They mostly change the character of its fluvial regime and the trending of its channel development. These changes increase risk of the human activities along the valley. To reduce this risk it is required to take coordinated actions in order to bring interstate management in line with the features of the formation of the channel.
Year: 2013