一、概述 伏尔加河是苏联五大河流之一(图1),发源于瓦尔代丘陵,汇合奥卡河、苏拉河、卡马河等数百条大小河流,往南注入里海。全长3,688公里,流域面积138万平方公里,几乎占俄罗斯平原的三分之一。从河源至河口总落差256米,平均比降万分之0.7。它的最大支流卡马河长2,030公里,流域面积52万平方公里,总落差263米,平均 I. Overview The Volga River is one of the five major rivers in the Soviet Union (Figure 1). It originated from the Valdeau hills and converged hundreds of rivers such as the Oka River, the Sula River and the Kama River, and injected southward into the Caspian Sea. The total length of 3,688 kilometers, the drainage area of ​​1,380,000 square kilometers, accounting for almost one-third of the Russian plains. The total drop from Heyuan to Estuary 256 meters, an average of 0.7%. Its largest tributary of Kama River 2,030 km, the basin area of ​​520,000 square kilometers, with a total drop of 263 meters, the average