The Rhine River in Alps (the upper reaches of the Rhine River in Switzerland) has the characteristics of alpine type (namely alpine type): steep slope, large flow (80% of precipitation in the basin area flows through the Rhine River in Germany), the water volume is obviously the smallest in severe winter, the water level is very high in spring due to snowmelt, and the water level is the highest in early summer due to heavy rain. The change of Rhine River can be regulated by Lake Constance, but it is increased due to its confluence with arles River. Lake Constance receives water from plateau streams and Rhine River, and plays a filtering role. The average water volume of the arles River is greater than that of the Rhine River. Below Basel, the Rhine River, a tributary of the plateau, has the largest water volume in spring at high altitude and in winter at low altitude, which is increasingly strengthening its role in regulating the flow imbalance of the Rhine River. Therefore, observed in Cologne, the average deviation between the Rhine River and the average flow is very small, and the river is beneficial to shipping. In addition, the seaworthy area of the Rhine River is generally mild in winter, and the river occasionally freezes in winter. Hydrological characteristics of the Rhine-the water level is full all the year round; Slow flow rate (because the terrain is flat), average; Spring and summer are the flood season (because the snow in the Alps melts), and the seasonal changes are obvious, with the peak in June-July; Water temperature changes with air temperature; There is no ice age in most river basins. Other features: It is the longest navigable river in Europe.