Fig. 1

The distribution of dams, catchment boundaries, and sampling sites in this study is illustrated as follows: (a) the upper Yellow River basin, (b) Longyangxia Reservoir, (c) Lijiaxia Reservoir, and (d) Liujiaxia Reservoir. The short black lines represent the dams, while the red circles indicate the sampling sites within the reservoirs, and the blue circles denote the sampling sites along the main stream. Detailed geographical information regarding the sampling sites is provided in the Supplementary Information (SI, Table S1). The map was created using ArcGIS Pro 3.1.2 (available at https://www.esri.com/en-us/arcgis/products/arcgis-pro/).