Water resources variation characteristics in the Ningxia section of the Yellow River

In the past decade, due to the rapid economic, social development impacts and global climate change in the upper reaches of the Yellow River, Yellow River water flowing into Ningxia has been substantially reduced, resulting in Ningxia exit water also decreasing, and the water consumption (entry and exit water difference) has increased. In this paper, a comparative analysis of the Yellow River in the Ningxia section from 2001 to 2012 and from 1956 to 1995 data showed that the average entry water decreased by approximately 18%, leaving an average of approximately 23% less water in many years, and Ningxia Yellow River water consumption increased by approximately 48%. Regarding the water impact from Meili canal, Qixing canal, Qing Tongxia east and west main canal, the annual flux above Qing Tongxia Reservoir from 2001 to 2012 was 211.73 m3/s. The water withdrawal and consumption of the Ningxia section of the main stream of the Yellow River showed a decreasing trend from 2000~2022, with an average water consumption of 3.699 billion m3, and the annual water consumption was relatively stable, which did not exceed the Ningxia quota water distribution plan of the State Council (no more than 4 billion m3 before the South-to-North Water Diversion Project came into effect) in the 1987, and the ratio of water consumption to water withdrawal gradually increased, and the water use efficiency was significantly improved.More water in irrigated areas from the Shi Zui Shan section of the Yellow River once again returned to the Yellow River, and flow in the Ningxia exit section of the Yellow River rather than the Qing Tongxia station increased by 102.99 m3/s. Due to the irrigation water from late March, the amount of entry water exceeded that of exit water in the Yellow River in the Ningxia section. In addition, effective irrigation due to precipitation increased in August, and the difference between water consumption decreased with the withdrawal of water in irrigated areas in the downstream segment. Thus, the exit flow from the Shi Zuishan section rather than the entry of water exhibited increase in September, October and December.