Fig. 2

Overview of the location of the Yellow River Basin (Note: This map is based on the standard map with the serial number GS (2020) 4631 downloaded from the standard map service website of the Bureau of Surveying, Mapping and Geographic Information of China (http://bzdt.ch.mnr.gov.cn/), and it was produced through ArcGIS 10.6 software (https://support.esri.com/en/download/7583). No modification has been made to the boundaries of the base map, and it does not require any permission from any source. The production methods of Figs. 5 and 6 below are the same as that of this map).