Seasonal variation process of wind and hydraulic action in Wuding River

The seasonal change process of wind and hydraulic action in the Wuding River is that the Wuding River basin is in the transition zone from wet to dry in China, with less precipitation in winter, windy weather, mainly the action of wind, concentrated precipitation in summer and obvious running water.

Wuding River, a first-class tributary of the Yellow River, is located in the north of Shaanxi Province, China. It is the largest river in Yulin area of Shaanxi Province. It originated at the northern foot of Baiyu Mountain in Dingbian County, and its upstream is called Liu Honghe. After flowing through Jingbian New Bridge, it is called Wuding River. The total length is 49 1 km, and it flows through Dingbian, Jingbian, Mizhi, Suide and Qingjian counties, and flows into the Yellow River from northwest to southeast.

The upper reaches of Liu Hong are located at the east foot of Liangdong, southeast of Dingbian, and flow to the southeast. Along the way, tributaries such as Nayuxi River, Luhe River, Dali River and Huaining River join the Yellow River at the estuary of Qingjian County. Wuding River has a large amount of coarse sediment transport, which is the largest river in Shaanxi Province. There are irrigation projects such as Zhinu Canal, Dinghui Canal, Second Dinghui Canal and Suihui Canal in the basin.

The runoff of Wuding River has obvious regional differences and decreases from east to west. The annual runoff depth to the east of Yulin is more than 80mm, to the east of Hengshan is more than 60mm, to the east of Jingbian is more than 40mm, and to the west is only 20 mm.. The runoff modulus also reflects that the southeast is greater than the northwest, because the southeast is close to the rainstorm center of Kuyehe River, and the precipitation decreases from southeast to northwest, and the southeast is loess area.

Annual runoff of Wuding River

The multi-year average flow of Wuding River10.53 billion cubic meters, accounting for 2.4% of the multi-year average flow of the Yellow River basin, and the basin area accounts for 4.2% of the Yellow River basin area, with relatively poor river runoff.

The water in Wuding River is mainly precipitation and groundwater recharge. In desert areas, due to strong ground leakage, groundwater recharge accounts for a large proportion, generally reaching more than 80% ~ 90%, and Hailiutu River can account for 77.6%. In the hilly and gully region of the Loess Plateau, precipitation is the main source of recharge, and groundwater recharge only accounts for about 30% of the annual runoff.