Why does the water recede in winter?

Because there is little rainfall in winter, shallow groundwater is mainly replenished by precipitation. If there is no rainfall, the recharge will be less, and the water level will certainly drop, which is what groundwater professionals call the dry season. The intuitive performance is that the water level of the river drops, and the water may not be seen, which is characterized by cutoff.

The conditions of deep groundwater are complex, which requires specific analysis of specific problems. Of course, there is another possibility that there is a large-scale pumping around, which will lead to a decrease in groundwater around, but this has little to do with the season and is generally continuous.

Moreover, the air is dry in winter, the water evaporation rate increases, and the water consumption for industry, agriculture and family life does not decrease. Whether it is rain-fed, snow-fed or glacier-fed, the water level of rivers and reservoirs will naturally decrease when the input decreases and the output increases. River recharge can be divided into rainfall recharge and ice and snow recharge.

1. The runoff of rain-fed rivers changes with the change of rainfall. In the rainy climate area all year round, the seasonal variation of runoff is small; In summer and winter rainy climate zones, runoff has seasonal variation.

2. The runoff of rivers replenished by snow and glaciers changes with the change of temperature. Interannual variation characteristics of runoff: monsoon climate, precipitation and runoff change greatly.

The reason why the river retreats.

1. Rivers will decline because the recharge of groundwater can't keep up with the consumption rate. For example, rainfall is obviously reduced, rivers are diverted, and human beings are overexploited.

2. The decline of rivers is also caused by geological changes. For example, the terrain raised by the earthquake and the underground river sank.

3. River water and groundwater around the river are complementary. Once the river is diverted, the groundwater level will decrease.